Baider Fabienne
email: fabienne@ucy.ac.cy

ANALYSING JOURNALISTIC DISCOURSE AND FINDING OPINIONS SEMI-AUTOMATICALLY? A CASE STUDY OF THE 2007 AND 2012 FRENCH PRESIDENTIAL CAMPAIGNS

This research study tested three different NLP technologies to analyze representative journalistic discourse used in the 2007 and 2012 presidential campaigns in France. The analysis focused on the discourse in relation to the candidate's gender and/ or political party. Our findings suggest that using specific software to examine a journalistic corpus can reveal linguistic patterns and choices made on the basis of political affiliation and/or gender stereotypes. These conclusions are drawn from quantitative and qualitative analysis carried out with three different software programs: SEMY, which semi-automatically provides semantic profiles; ANTCONC, which provides useful Keywords in Context (KWIC) or abstracts of texts, as well as collocations; TERMOSTAT, which reveals discourse specificities, frequencies and the most common morpho-syntactic patterns. Analysis of our data point to convergent asymmetries between female and male candidates in journalistic discourse (however conditionally) for the 2007 and the 2012 French presidential campaigns. We conclude that social gender (i.e., stereotypical expectations of who will be a typical member of a given category) and / or political favoritism may affect the representation of leadership in discourse, which, in turn, may influence the readership, hence the electorate. Thus the study recommends the use of corpus linguistic tools for the semiautomatic investigation of political texts.

Introduction

Research analyzing ideology in discourse [START_REF] Baider | How to make people feel good when wishing ill: Golden Dawn and National Front Discourse, Emotions and Argumentation[END_REF][START_REF] Kohl | The Presentation of "Self" and "Other" in Nazi Propaganda[END_REF][START_REF] Reutenauer | De l'annotation sémique globale à l'interprétation locale : environnement et image sémiques d' 'économie réelle' dans un corpus sur la crise financière[END_REF][START_REF] Valette | Propositions pour une lexicologie textuelle[END_REF][START_REF] Mussolff | What can critical metaphor analysis add to the understanding of racist ideology? Recent studies of Hitler's anti-Semitic metaphors[END_REF] has shown that the indexicality (indirectness) of the construction of prejudices in discourse, i.e., the lexical and stylistic choices, can impart an ideological (racist or sexist) semantic prosody to a text without the text being explicitly racist or sexist. Therefore, the lexical specificities that characterize a discourse can reveal an ideological position. The purpose of this article is to show how software such as ANTCONC, SEMY and TERMOSTAT [START_REF] Drouin | Term extraction using non-technical corpora as a point of leverage[END_REF][START_REF] Lesage | Enquête sur l'état d'utilisation des outils automatisés d'aide à la rédaction dans les organisations[END_REF]) can help to identify the ideological stance of a discourse. Our studies analyzing journalistic data (2007 and 2012 election campaigns in France) show that results found in a semi-automatic way offer a fairly good picture of and basis for comparison of political profiles and campaigns. After a brief review of the literature on interface, language, media and gender issues, the study data and methodology are presented. Our data (journalistic discourse) are drawn from specific candidates participating in the presidential campaign; our methodological tools are capable of identifying lexical preferences (NP extractor, concordance and syntactic parser). In the final section of the article we analyse the results, arguing that such software helps to verify, invalidate or refine results obtained in previous qualitative studies or manual readings: specifically, they offer complementary results to detect specific lexical and stylistic features. Nevertheless, we add the caveat that the software results and analyses must be considered in conjunction with a close manual reading and a good knowledge of the social context. In this way, we can verify whether the findings are plausible and arrive at the most accurate interpretation of the lexical findings.

Previous work

According to van Dijk's theory (2006 et passim) the overall strategy of an ideological discourse comprises a dichotomous positioning between several entities:

-positive presentation /action of our preferred candidate, our party, our electorate, etc., emphasizing the positive and downplaying the negative; -negative presentation/ action of the other candidate, the other party, the other electorate, etc., emphasizing the negative and downplaying the positive. In order to present a specific viewpoint along a certain ideological continuum, different linguistic devices are used, including certain lexical units, grammatical constructions, metaphors, irony, etc. This dichotomous positioning can, in fact, be accomplished in the most indirect fashion.

Indexicality of ideology and linguistic choices

As mentioned in our introduction, ideology in discourse is mainly indexical [START_REF] Van Dijk | Discourse and manipulation[END_REF]. Therefore, Vallette and Rastier (2006, 4) were able to identify racist content in online documents by observing language choices that resulted in a text with the illocutionary force of a racist text, but which was not explicity racist. For instance, with reference to morpho-syntax, indexical racism was characterized by an intensive use of evaluative adverbs and negative adverbs (nothing, never, much, too much, etc.), and an intensive use of the first person plural pronoun in order to build an opposition between us and the other(s), as well as a predominant usage of pejorative morphemes.

In a similar vein, earlier research on sexism in discourse noted that language choices can indeed build semantic oppositions and discourse asymmetry between the described entities without being obvious [START_REF] Ochs | Indexing Gender. Rethinking Context : Language as an Interactive Phenomenon[END_REF][START_REF] Kitzinger | Is 'woman' always relevantly gendered?[END_REF][START_REF] Goodwin | Engendering Children's Play: Person Reference in Children's Conflictual Interaction[END_REF]. Working on sensationalist discourse (such as in the UK newspaper The Sun), [START_REF] Clark | The linguistics of blame. The Feminist critique of Language[END_REF] observed the shifting of blame in sexual violence onto the victims by analyzing 'naming' and 'transitivity' 1 (1998, 183-185). She concluded that different connotations of approval and / or legitimacy are expressed by these linguistic patterns. In the field of education, several studies (Lazar 2005;[START_REF] Penelope | Speaking Freely: Unlearning the Lies of the Fathers' Tongues[END_REF]) have shown that many English-language textbooks use men and boys for the agents or doers, while when they want to depict negative traits they use women and girls. [START_REF] Bergvall | Cultural Projections in Constructed Linguistic Examples: Gender Representations in Introductory Texts[END_REF] and [START_REF] Macaulay | Don't touch my projectile: Gender bias and stereotyping in syntactic examples[END_REF] have concluded that the examples used by linguists to illustrate syntactical phenomena reveal an under-representation of females especially in examples indicating agency (9%), as well as a negative semantic prosody since they present women as passive, incompetent and talkative. This was despite the recommendations from the LSA (Linguistic Society of America) regarding the construction of examples.

Similarly, in their examination of discourse in scientific texts in French, [START_REF] Michard | Some socio-enunciative characteristics of scientific texts concerning the sexes, the nature of the right. A feminist analysis of order patterns[END_REF] and Michard and Ribery (1998) concluded that females were constructed as 'non-agent ' entities (1998[2008], 174-184) because of the specific verbs and/or nouns referring to them, as well as the presence of particular adverbs and adjectives (high incidence of few, a little, a few, less). Combining their syntactic and lexical findings, Michard and Ribery concluded that a power relationship between the described entities can be established discursively.

Indeed such an asymmetry may explain the functions and the qualities assigned to one person versus the other in concrete social situations such as the political arena.

Journalistic discourse, leadership and indexing gender

Many studies on leadership have concluded that gender plays an important role in the perception of a public persona. Some studies argue that, even though the negative perception of female politicians shown by their peers can be attributed to a complex interplay of factors, it can also be partly attributed to the way female politicians draw (if they do) on gendered linguistic resources (Shaw 2013, 39). Meanwhile other studies have found that that among male and female managers who use similar verbal constructions, the women will be viewed rather negatively [START_REF] Sung | Media Representations of Gender and Leadership: From a Discourse Perspective[END_REF][START_REF] Thimm | Communicating gendered professional identity. The Handbook of Language and Gender[END_REF]. Looking at the media, [START_REF] Cotter | Women's place at the Fourth Estate: Constraints on voice, text, and topic[END_REF] studied two key parameters in the news media that would represent a change in the role of women and their visibility in society: bylines (who is entitled to be recognized by name when writing an article) and story topic (what counts as salient in the journalist's world). Both are elements of prestige in the journalistic discourse community. Cotter concluded that despite increased opportunities for women over time, the position occupied by women relative to men, family, and 'the economy has not changed to the degree we sometimes think it has' (2011,2532). This finding can partially explain the gender disparities observed in journalistic discourse. Many researchers have noted a discursive asymmetry in relation to female and male politicians [START_REF] Kahn | The distorted mirror: Press coverage of women candidates for statewide office[END_REF][START_REF] Kahn | The political consequences of being a woman: How stereotypes influence the conduct and consequences of political campaigns[END_REF]Sreberny-Mohammadi & Rossi 1996;[START_REF] Roncarolo | A woman at the quirinal: Thanks, but no thanks. The social construction of women's political agenda in the 1999 Italian presidential election[END_REF][START_REF] Coulomb-Gully | Présidentielles 2007 : Média genre et politique[END_REF], 2012;[START_REF] Bertini | Femmes, le pouvoir impossible[END_REF]. Furthermore, most studies that examined French politicians in the written and oral corpus raised the issue of gender--the gender of the entity described, as well as the gender of the entity writing the text. Thus [START_REF] Caillat | Le recours au discours rapporté dans le débat présidentiel de l'entre-deux tours de 2007 : des usages sexués? Les discours rapportés dans les discours médiatiques, une affaire de genre[END_REF], [START_REF] Rabatel | La parole des politiques soumise à contre-enquête' représente-t-elle de la même façon la parole des hommes et des femmes politiques ? Les discours rapportés dans les discours médiatiques, une affaire de genre[END_REF] and [START_REF] Devriendt | Du discours rapporté dans deux séquences médiatico-dis,cursives de la pré-campagne présidentielle française 2012: candidats vs. candidates, une loi du genre? Les discours rapportés dans les discours médiatiques, une affaire de genre[END_REF] showed how the reported speech in journalistic discourse was adapted differently when comments referred to a female candidate or to a male candidate in the 2012 presidential campaign. Similarly, Barnes and Larrivée (2011), [START_REF] Moores | Women in the presidential race: Arlette Laguiller and Dominique Voynet[END_REF] [START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF] examined how female and male politicians are constructed in the French newspapers. They all concluded that discourse practices and lexical choices play a critical role in the construction of the entities described as either incompetent or the opposite, as the perfect leader. However the ideological distance between the newspaper and the candidate suggests that power struggles are a primary source of asymmetrical treatments as much as gender [START_REF] Julian | Arlette Laguiller: Does the mainstay of the French political far-left enjoy linguistic parity with her male counterparts?[END_REF][START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF][START_REF] Moores | Women in the presidential race: Arlette Laguiller and Dominique Voynet[END_REF]): indeed, Barnes and Larrivée (2011, 2507) found that a right-wing newspaper referred to the left-wing female politician (Arlette Laguiller) by her first name alone because of her political affiliation and not because of her gender. Usually, however, such negative treatments are not used unless an important competition is at stake [START_REF] Moores | Women in the presidential race: Arlette Laguiller and Dominique Voynet[END_REF][START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF].

The above-mentioned studies all have drawn the general conclusion that the indexicality, or indirectness, of ideological positioning renders (semi)-automatic reading difficult. Therefore, how can we evaluate such positioning in discourse? Since the studies above point to lexical specificities in a discourse that (indirectly) represent an ideological position, we could focus our analysis on the most frequent and specific lexical units in our data to test the hypothesis that these units will represent a certain point of view.

Indexicality and corpus linguistics

Much research on political analysis has used software to extract lexical units with the aim of identifying patterns, which might then, in turn, explain either the motivation for the word choice or the impact of the word choice. They all conclude that rhetoric and word choices are fundamental to supporting political strategies. For instance, the typical style of political journalists, which reports on political life primarily through quotations or small excerpts, leaving aside much of the rest of the speech confirms this finding (Saitta 2008). [START_REF] Brasart | Petites phrases et grands discours[END_REF], in his study of 'petites phrases' in French political discourse, demonstrated the existence of linguistic practices used by politicians to make an impression on the audience. Semi-automatic readings allow us to examine how and to what degree politicians fit these expressions into their strategic rhetoric; they know that their words will often be reduced to a few sentences and they might well anticipate this and prepare for it [START_REF] Krieg | Les ''petites phrases'' : un objet pour l'analyse des discours politiques et médiatiques[END_REF]. Quantitative observation can help us evaluate changes in political speeches, allowing us to bypass the axiological dimension that frequently marks both the discourse and its analysis. Corpus analysis using semi-automatic reading can also assess the evolution of the professionalization of communicative labor policies and underlying standards expressible in politics. For instance, [START_REF] Marchand | Genre, style et attitude à l'égard du langage : tentative de diagnostic automatique sur un corpus politique[END_REF] showed that computer-assisted discourse analysis (statistical text analysis, morphosyntaxic analysis) can contribute to the diagnosis of genre, style and attitude in language. A recent study of statements made by the French prime ministers of the Fifth Republic [START_REF] Dupuy | Évolutions lexicales des débats de l'entre-deux-tours de l'élection présidentielle française[END_REF] showed that by looking at frequency and specificity they were able to note a shift in lexical choices. Their study concluded that this change in word choices would also reflect a change in the focus of the presidential debates in France: and, in fact, since 2000 debates have moved away from issues closely related to the social fabric such as education and environment, to focusing on economic and financial issues (even when referring to education). This focus is one more commonly found among managers and economists, which could be interpreted as a move towards neo-liberalism on the part of mainstream politicians.

Interpretation of such data requires interdisciplinary knowledge, and this has been true since the first major work published in the field, by [START_REF] Kucera | Computational Analysis of Present-Day American English[END_REF], who subjected their data to a variety of computational analyses, combining elements of linguistics, language teaching, psychology, statistics, and sociology. This interdisciplinary analysis can be carried out within a framework that integrates findings at the micro-level of language into the macro-level of society (societal rules, social actors involved, etc.). Therefore in our analysis of the data we will consider language as a form of social practice and will apply principles of critical discourse analysis (CDA) (Fairclough 1989, 22), i.e., we will consider that linguistic data are not external to society but are, in fact the opposite, conditioned by other (nonlinguistic) parts of society.

Corpus, Methodology and Tools

Data and data analysis

CDA explores the often 'opaque relationships of causality and determination between discursive practices and wider social and cultural structures, relations and processes' (Fairclough 1995, 132;[START_REF] Widdowson | On the limitations of linguistics applied[END_REF]. Such practices arise out of and are ideologically shaped by relationships and struggles related to power (Fairclough 1995, 133), while the indexicality of such relationships between discourse and society would itself be a factor securing hegemony (Fairclough 1995, ibid.;[START_REF] Ochs | Indexing Gender. Rethinking Context : Language as an Interactive Phenomenon[END_REF]. Our analysis will consider the macro-context in which the discourse occurs, i.e., its social reality, after having studied the micro-level, i.e,. the text itself, collocations, frequencies, etc. Therefore we will interpret the data taking into account the social reality of French politics, the French political culture and journalistic practices.

The purpose of the next two sections is to present our data and show how software such as SEMY [START_REF] Mick | Systèmes complexes et analyse textuelle : Traits sémantiques et recherche d'isotopies[END_REF] 2 or TERMOSTAT [START_REF] Drouin | Term extraction using non-technical corpora as a point of leverage[END_REF][START_REF] Lesage | Enquête sur l'état d'utilisation des outils automatisés d'aide à la rédaction dans les organisations[END_REF]) can help identify either the recurrent semantic elements or the specificities of the data and, as a result, point to the ideological positioning of discourses in journalistic corpora.

We undertook three separate studies focused on the journalistic discourse during the 2007 and 2012 presidential campaigns in France, campaigns where female candidates had a chance to win--whether in the primaries of their party (Aubry in 2012) or in the second round (Royal in 2007). The first study contrasts the contextual environment of the names of the three main candidates during the 2007 presidential campaign (Bayrou, Royal, Sarkozy) in order to assess their semantic profile in the journalistic discourse, and to assess whether gender was a factor in the word choices by journalists. The second study follows the same pattern but focuses on the textual environment of the candidates in the smaller parties (i.e., Communist, National Front, Green, etc.), to see if the same patterns occur as those identified in the first study. The third study contrasts the contextual environment of the names of the two main candidates in the 2012 socialist primaries (Aubry, Hollande) to check whether two candidates from the same party would be presented with different discourse strategies in the same newspapers.

Our data for the 2007 presidential campaign (partially published in [START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF][START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF]Jacquey 2010) were collected over the 12 months prior to that year's elections; data was collected for the candidates Royal, Bayrou and Sarkozy as recorded in the newspaper Le Monde. We collected 330 articles (roughly 100 for each candidate) that focused on a candidate, i.e., containing the name of the candidate in the title and several times in the text. All candidates were represented by a comparable word count (roughly 19, 000 words for each candidate, almost 60, 000 words). This methodology and size of data are compatible and comparable to the earlier studies in language, gender and politics referred to earlier (section 1.2). These studies also used relatively small corpora (Barnes & Larrivée worked on roughly 32,000 words; Fracchiola focused on one debate since her aim was a qualitative study of politeness strategies). 3 Moreover, Barnes & Larrivée used the same methodology as we did (i.e., they started out with the name of the politician in the title and then looked at the focus of the article with the repetition of the name in the body of the text), making our methodology and corpora directly comparable.

Our data for the 2012 socialist party primaries was taken from the Factiva database: twenty (20) articles for each candidate from each of six different newspapers (national dailies: Libération, Le Monde, Le Figaro, La Croix; regional dailies Ouest-France, Est-Républicain). Articles focusing on Aubry and Hollande were chosen from periods considered as the most decisive for the socialist primaries, i.e., March-May 2011 is the period before the Strauss-Kahn fiasco4 ; June-July 2011 is the period just after the DSK announcement that he would not run; September-October 2011 is the time of the socialist primaries. There are two versions of every folder on the politicians: the first version contains all the articles for each candidate sorted according to newspaper; the second folder is text alone, with no details on the source. We have a total of 120 articles for Aubry and Hollande.

Previous research has suggested that analyzing discourse practices through a focus on particular on noun phrases (NPs) referring to female and male politicians could be a way to assess the 'linguistic profile' of politicians in journalistic discourse, especially their agency [START_REF] Eckert | Language and gender[END_REF]. Agency is fundamental in discourse, since one could assume that to be elected, the candidate must be perceived and constructed as a leader (associations with dynamism, initiative, courage, etc.), which in effect means to be constructed and perceived as an agent, someone in control of the environment. This semantic value also has a pragmatic outcome: the described entity will more likely be perceived as a leader and therefore as the candidate to be elected. In order to assess the lexical environment of each NP under study, we used tools that can process a considerable amount of data, thus enabling us to quickly identify lexical choices. This makes a quantitative and a qualitative reading very feasible.

Methodology and Tools

Frequency and specificity are the most common criteria for corpus analysis, as previous studies on ideology and discourse have noted [START_REF] Marchand | L'analyse de similitude appliquée aux corpus textuels : les primaires socialistes pour l'élection présidentielle française (septembre-octobre 2011)[END_REF]Michard & Ribery1998[2008]; [START_REF] Valette | Prévenir le racisme et la xénophobiepropositions de linguistes[END_REF]. Moreover, lexical units such as derogative adverbs and negative adjectives are considered the most relevant to ideological loading [START_REF] Reutenauer | De l'annotation sémique globale à l'interprétation locale : environnement et image sémiques d' 'économie réelle' dans un corpus sur la crise financière[END_REF][START_REF] Valette | Propositions pour une lexicologie textuelle[END_REF]) and more likely to be found in references to a 'subordinate entity.' Regarding methodology, most recent research using corpus linguistic methodology for study of the 2012 presidential campaign (e.g., [START_REF] Marchand | L'analyse de similitude appliquée aux corpus textuels : les primaires socialistes pour l'élection présidentielle française (septembre-octobre 2011)[END_REF] suggests that discursive strategies can be understood through an investigation based on semi-automatic reading.

Indeed, in recent years several software packages have been produced that are able to extract lexical and syntactic patterns characteristics of the type of data under investigation in the present study. Gender specificities were identified by using these programs, specifically, ANTCONC for providing statistical concordance functions; TERMOSTAT for term extraction; and SEMY for extraction of semantic fields. These programs were chosen because they were among the most readily available and free of charge. 5 Further, these are also the programs with which the author is most familiar.

ANTCONC : ANTCONC 6 provides concordances, collocations, frequency lists, word lists and key word in context (i.e., the line in which the word was used). Especially when there are many concordances, ANTCONC is user-friendly and quickly downloaded from the Internet onto the computer. Most importantly for researchers working on different alphabets, the software supports many different languages, including those using the Cyrillic (Greek, Russian) as well as Chinese, Japanese, Korean, etc., alphabets.

ANTCONC enabled us to carry out a qualitative analysis since we can isolate blocks of text where the NPs are present; in this way we can visualize the contexts of use of any key word (see Graph 1 below, which illustrates what is defined as a key word in context or KWIC). A manual and selective reading is then possible. The software also extracts and displays collocations, frequencies and word lists. In particular, the categories 'collocates' and 'cluster' allowed us to check whether some NP are more often associated than others with evaluative lexical units (see Michard & Ribéry 1987;[START_REF] Valette | Propositions pour une lexicologie textuelle[END_REF]. We can very quickly verify a higher number of adverbs, adjectives and negative modifiers such as un peu, quelques, moins collocated with the NPs under investigation. Moreover, a manual reading can point out the syntactic processes most associated with these NPs (subject of a sentence for instance) and the agency of a unit (among other thematic roles, cf. [START_REF] Dowty | Thematic proto-roles and argument selection[END_REF]. Therefore, with these abstracts we can observe whether NPs are constructed in discourse as a non-animated entity or at least as less in control of the verb (if they are most often subjects of a verb but non -agents, for instance).

TERMOSTAT: TERMOSTAT [START_REF] Lesage | Enquête sur l'état d'utilisation des outils automatisés d'aide à la rédaction dans les organisations[END_REF] 7 identifies grammatical categories and allows us to quickly see which nouns, adjectives or adverbs are the most used or the most specific in the data. Although the software presents features complementary to ANTCONC, it does not fully support languages other than French and English. The TERMOSTAT platform extracts the frequency and specificity of simple and complex lexical units relative to a reference corpus. The data integrated to the TERMOSTAT platform as reference corpus includes 28 million occurrences from Le Monde (2002) 5 There are many tools used in corpus linguistics. Among the free engines, there are Iramuteq (University of Toulouse) http://iramuteq.org/ for French, and Lexico 3 (University of Paris3) http://www.tal.univ-paris3.fr/lexico/ for French and English, as well as TXM Unicode-XML-TEI text/corpus analysis platform which the most complete tool for the Humanities among the freeware: http://sourceforge.net/projects/txm/files/corpora/brown/. Among the tools for corpus linguistics which are not free, Sketch engine is (according to the author of this paper) is efficient and user-friendly; it also supports most languages: http://www.sketchengine.co.uk/ 6 http://www.antlab.sci.waseda.ac.jp/software.html (Drouin 2003) 8 . From this we can identify a list of the most salient terms in our data, ether because they are the most frequent or because they are the most specific to the discourse. TERMOSTAT was developed from the research of [START_REF] Ludovic | Statistique textuelle[END_REF], who quantified the specificity of a term based on its the test-value, which is a standardized view of the frequency of the lexical units (Drouin 2003, 3). We used TERMOSTAT to examine the most specific lexical categories for each NP investigated (i.e., Aubry, Hollande), criteria which are the basis of our hypothesis. We can subsequently determine which categories are most relevant to a qualitative reading. In Table 1 below we can observe the most specific lexical units for the name Hollande, when compared with the reference corpus of TERMOSTAT: While linguistic expressions such as primaire socialiste 'socialist primaries' and investiture 'nomination, investiture' are expressions that we might expect to be specificities of a political text, in order to understand expressions such as président normal and humour corrézien, we must have some knowledge of the candidate profile. Indeed both are topoi that specifically characterize Hollande, whose campaign was organized around the axis of 'normality,' and whose humor, as well as the fact that he was responsible for the Correze district, were well known by the French. Nevertheless, even if one knows nothing of the candidate, the incongruity of both linguistic expressions and the fact that they are specificities of the candidate profile will trigger the attention of the researcher.

As we can see in Table 2, there is also other information relating to the linguistic profile of the data provided by TERMOSTAT such as9 :

the various 'physical appearances' of this expression in the corpus (plural or feminine forms for nouns for instance);

-the grammatical category of the lexical unit.

These features allow a thorough quantitative reading of a corpus and enable comparison between corpora.

SEMY: SEMY is one of the rare software programs that is semantic based and is applicable to the French language. It is unfortunately only available at the ATILF.

Working with semantic fields is important and SEMY aims to give a semi-automatic semantic profile of texts or linguistic entities. Indeed when fed a text or a noun, the platform automatically extracts a lexicon based on the digitalized Trésor de la language française and gives the semantic field of each word in the shape of a list which Rastier would call a SEMEME. 10 .The list provided is very similar to the one provided by TERMOSTAT, although it describes semic features and not lexical units. On the basis of the textual files provided, SEMY will give lists based on the semantic recurrence in each file, i.e., using the most salient semantic feature in the data. The researcher is then tasked with making sense of all the units presented; he/she must find a correlation in order to arrive at a semantic profile. To do so, we group together the semic features found in the list using the CRISCO synonym dictionary.11 For instance, the verb communiquer 'to communicate' was found as a recurrent semic feature in Royal's SEMY. We look into CRISCO and find a series of verbs which are in the same semantic field as communiquer, such as montrer 'to show' or déclarer 'to declare.' In turn some of these verbs are also found in SEMY'S list for Royal, and we can then organize the data accordingly, in the same semantic field. These three verbs were very much present in the Royal data, and much less so in the Sarkozy data. This grouping, we suggest, allows us to describe the semantic profile of the NPs Royal and Sarkozy in the journalistic discourse under study. In the next section we report the data found with each software program and discuss our results.

Report and discussion of the results

Does the semantic profiling of a noun indicate gender stereotyping?

We used both SEMY and the 2007 data to work on the semantic profile of an entity in a text since the stakes were very high: Royal was the first woman candidate to make it to the first presidential round, and she was competing against Sarkozy.

During the campaign Royal complained about unfair treatment by the media, saying that they, for instance, portrayed her failures or gaffes much more often than Sarkozy's,. And, in fact, the newspaper Le Monde apologised for focusing on her 'blunders' [START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF].

As mentioned earlier (section 2.3, SEMY), the most salient dimension of Royal's candidate personality was the relational aspect. Therefore we used the CRISCO dictionary to categorize the semic features, which then allowed identification of the semantic fields for the candidates according to SEMY (Table 3)

CANDIDATE NAMES SEMANTIC FIELDS RECURRENT SEMIC FEATURES IN CORPUS

Nicolas Sarkozy Planning viser "to aim", chercher "to seek", poser "to set up", vouloir "to want", envisager "to envision", compter "to reckon

Argumentation

Entretenir "to converse", contredire "to contradict", jouer "to play (on words) " Action signer "to sign", embaucher "to hire", agir "to act"agir, embaucher "to hire", partir "to leave" Ségolène Royal

Political campaign

Voter "to vote", préférer "to prefer", élire "to elect", désigner "to appoint",

Communication

Appeler "to call", déclarer "to declare", annoncer "to announce", exprimer "to express", proposer "to suggest", téléviser "to relevise"

Defensive

Inquiéter "to worry", renoncer "to giveup", défendre "to defend"

François Bayrou Debate estimer "to evaluate", être favourable "to be in favour", être contre "to be against", denouncer "to denounce" Progress progresser "to progress", conforter "to consolidate", poursuivre "to pursue", proposer "to suggest" and gagner "to win") Table 3. Semantic fields identified with SEMY [START_REF] Baider | Substantive Dis-Embodiement, Syntactic Embedment. Feminism, Femininity and Gendered Discourse[END_REF] In the context of the name Royal, 50% of the features listed by SEMY belonged either to the field of COMMUNICATION (such as to call, to declare, to announce, to express, to suggest), or to the field of POLITICAL CAMPAIGN (to vote, to prefer, to elect and to appoint). In the case of her male opponents the semantic profiling was quite different. Regarding the name Sarkozy, the most salient dimensions were the field of ACTION (to sign, to hire, to act, to do, to depart), and the field of OBJECTIVES (to aim, to search, to covet, to want, to consider, to reckon, to wish). The semantic profile of the name Bayrou also emphasized ACTION towards a goal, but in a more positive fashion than for the name Sarkozy (to progress, to consolidate, to continue, to want, to offer, to make); it further emphasized REBELLION (to be unfavorable, to be against, to denounce, to disapprove, etc.). A comparison of the three semantic profiles, we can we identify the gender stereotype defining the female versus male candidates reveals them defined according to the opposition ACTION (male) vs. COMMUNICATION (FEMALE). This opposition recalls the cliché of women being good in relating to people and men being better in taking steps and making decisions.

These results can be explained in a number of ways: by the discourse of the candidates, by their behavior (Royal and Sarkozy both played on sexual stereotypes), or by the journalists' perceptions of the politicians. It is impossible to identify the source of the difference--but the difference is there.

From a semantic point of view, SEMY has revealed what we call the 'deep structure' of the names Bayrou, Royal, Sarkozy, as constructed in discourse. The TERMOSTAT software [START_REF] Drouin | Term extraction using non-technical corpora as a point of leverage[END_REF][START_REF] Lesage | Enquête sur l'état d'utilisation des outils automatisés d'aide à la rédaction dans les organisations[END_REF], however, reveals another facet of the meaning, as it identifies the specificities of words found in the context of each name and confirm a difference for each name. This is the topic of the next section.

Antconc, KWIC abstracts and agency: power in politics?

With the concordance supplied by ANTCONC, we analyzed the KWIC abstracts (see section 1.3). To evaluate agency, we focused on the syntactic functions of the names, considering that Eckert and McConnell-Ginet argue that any NP in the position of subject in a sentence will be associated with power and control (2003,52). We also evaluated the semantic functions to examine the actual causality of each NP, and restricted our study to agent and non-agent categories [START_REF] Dowty | Thematic proto-roles and argument selection[END_REF]. This evaluation had to be done manually [START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF]), and we found that the syntactic choices made in journalistic discourse when referring to the presidential candidates revealed a partial dichotomy with the nouns (see Table 4). The noun Sarkozy functions more often as a subject than does the noun Royal. This contrastive study of syntactic choices used to describe a female versus a male candidate confirms a perception of the journalists conforming to stereotypes: the noun for the male candidate is, syntactically, in control of the verb, while the noun representing the female candidate is its subordinate. There was an even greater difference with regard to the semantic functions. [START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF] The male candidate is constructed first as an agent, which concurs with SEMY findings. In contrast, the female candidate's name most often played the role of an aim (for Royal), a place (chez Royal) or a relation (de Royal), which we categorized as cause. Moreover, the noun Royal was described twice as frequently as an experiencer, i.e., a person who feels, than as a person who controls the action described in the sentence [START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF]. As a matter of fact, when both candidate names are in the same sentence, in 75% of cases the noun Royal is found in a clause embedded in the clause in which the noun Sarkozy is the subject, as the occurrences found in corpus show below [START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF]):

Sarkozy

(1) Prenant de vitesse Ségolène Royal, qui doit débuter, lundi 25 septembre, un voyage au Sénégal, Nicolas Sarkozy a effectué, l'avant-veille, un déplacement de quelques heures à Dakar ; 'Surprising Ségolène Royal, who will travel to Senegal on Monday 25 September, Nicolas Sarkozy, just a day ago made a short trip to Dakar'.

(2) Nicolas Sarkozy, qui battrait Mme Royal 36 % contre 34 %, (…) 'Nicolas Sarkozy, who would beat Ms Royal 36 % against 34 %, (…)

(3) M. Sarkozy croit que Mme Royal « le protège beaucoup ». 'M. Sarkozy believes that Ms Royal "protects him a lot"'.

The opposite is less likely to be found:

(4) Au moment où Nicolas Sarkozy s'apprête à rendre publique sa candidature (...) Ségolène Royal prend le large. 'As soon as Nicolas Sarkozy is ready to publicly announce his candidacy (...), Ségolène Royal takes a trip'

We can also observe that the semantic prosody [START_REF] Bednarek | Semantic preference and semantic prosody re-examined[END_REF]) in all the occurrences above are consistently negative for Royal: Royal is surprised by Sarkozy's quick move; whereas as soon as he announces his candidacy (an important move), she goes on a trip (a trivial endeavor)-here we also note the female candidate as the target of ironic observations (3) and ( 4).

The French press coverage of Royal during the 2007 presidential campaign may have been driven by and perpetuated a normative view of the sexes. However, the results may also be explained as much by the politician herself and her choices of words and personae. Therefore the linguistic profile could also be considered as an exception, but not the rule, given the results presented in the next section.

Smaller candidates: specificity, power and gender in politics

We conducted a second test to verify the validity of our previous hypothesis i.e. that studying newspaper political discourse might reveal a gender /power relationship established through linguistic choices. For this reason, we ran similar linguistic analyses on media coverage of less important elections with strong female candidates, investigating gender relevance when power is not as much at stake.

-In the 2007 presidential elections, we assessed the linguistic profiles of candidates with a smaller following, such as Voynet, Le Pen, -In the 2011 socialist primaries we analysed the specificities of the data for Aubry and Hollande who belong to the same party.

Qualitative reading, Semy and Antconc, the agency criteria

An earlier study that focused on the minor candidates in the 2007 elections (Baider & Jacquey 2010) did not reveal the same asymmetry observed for Royal and Sarkozy. Using the same methodology we identified semantic profiles and agency for candidates of smaller parties, including (Ms) Voynet for the Greens, (Ms) Buffet for the communist party and (Mr) Besancenot for the radical left--all candidates who had no chance to win.

The lexical asymmetry found in relation to Royal did not hold true for the other female candidates who are part of our study. For example, with regard to male and female candidates in general, negativity was more a masculine trait than a feminine one, whereas in the study with Royal, negativity characterized the female candidate. Indeed, the male noun Bové was defined by the field of Unlawfulness; Besancenot by the field of Discord and Le Pen (Mr) by the field of Concealment. The three female politicians were characterised, as was Royal, by their relational personalities, with the field of Advice for Buffet, of Moderation for Voynet and of Persuasion for Laguiller.

As far as grammatical choices are concerned, the female Communist party leader Buffet and her newly appointed male opponent, Besancenot, the Revolutionary Communist party representative, served as a case in point. Both names were considered together, since the NP Buffet and Besancenot are found in the same syntagm 89% of the time when they are coordinated with another NP (such as in Buffet et Besancenot). At almost all levels of discourse our results contradict the figures obtained with the NPs Bayrou, Sarkozy and Royal. Indeed: -The name Besancenot is used with another NP and therefore 'not autonomous' in 54% of the occurrences, whereas the name Buffet stands alone 35% of the times.

-The female candidate, Buffet, is twice as often an agent as her young male counterpart.

-On the lexical level, Besancenot, a Trotskyite, is also described as Alain Krivine's 'young protégé' (jeune poulain), Krivine being a well-known and longtime figure of the extreme left. The term 'protégé' reinforces his (just) burgeoning career. In contrast, the name Buffet co-occurs with the adjective fort (strong) and the noun chef (leader), signaling the long political career of the communist leader. Even when both names occur in the same sentence, no striking pattern of hierarchy can be noted: both names are used in the same clause, both function as a subject or as part of a prepositional phrase. The above-mentioned criteria are the only ones to differentiate the two discourses and they all favour the females candidates. In this we witness a situation where the stakes are not as high as those in a presidential election, and the same gender stereotypes in the political sphere are not apparent. For example, Buffet (the then communist party leader) was granted more agency than her young opponent Besancenot (the then extreme left leader). Is it perhaps that parity can be granted when there is not much to lose or to gain,12 as Moores observed in 1997.? However, as mentioned before [START_REF] Baider | Lexical change, discourse practices and the French press: Plus ça change, plus c'est la même chose? Language Variation -European Perspectives II[END_REF][START_REF] Baider | Substantive Dis-Embodiement, Syntactic Embedment. Feminism, Femininity and Gendered Discourse[END_REF], the Sarkozy and Royal candidacies were wellknown to be a somewhat exceptional case, since Royal and Sarkozy both played, and for the first time in French political history, on sexual stereotypes [START_REF] Gingras | Les métaphores dans le langage politique[END_REF][START_REF] Achin | Nicolas Sarkozy ou la masculinité mascarade du président[END_REF]Coulomb-Gully 2012).

Quantitative reading, Termostat, the specificity criteria

Although our data has been described already, we want here to reaffirm that we are investigating the socialist primaries in which one female and one male candidate were the final contenders. They were not the initial favorites, however; Dominique Strauss Khan (DSK) was clearly the favorite of the party until he was caught up in a scandal, which forced him to withdraw at the end of May.

Before the DSK affair

As Table 6 below illustrates, the most frequent terms associated with the two candidate names (as provided by TERMOSTAT) were terms found in articles focused on the political campaign (candidate, first round, vote, campaign, party nomination, meeting, etc.) However, if we look at the specificity criteria, and before the Strauss Khan fiasco, we see that the name Aubry is described extremely positively. Moreover, a close reading of newspaper discourse with TERMOSTAT revealed no blatant gender stereotyping in the six newspapers we used for our corpus. In fact, the opposite occurred: we observed reverse stereotypes. The discourse described the name Aubry as a dynamic and organised manager, and the name Hollande as an embattled politician busy dealing with conflict. In Table 7 below listing the specificities, we note three odd expressions typifying the candidates (i.e., after eliminating all the expressions common to both candidates).

In order to categorize the lexical units, first we used the interface of the morphosyntactic and semantic criteria (denoting positive or negative values) :

verbs (denoting action) are underlined, -adjectives (describing positive or negative assessment) in italics, -nouns (with a positive or negative connotation) in bold

We then grouped the lexical units according to their morphosyntactic categories.

Verbs, which can denote a more active and dynamic personality (or at least of a perception of a more dynamic person), are only found with the NP Aubry; none are recorded for Hollande: Aubry: MA says (dit Martine Aubry), MA does (fait Martine Aubry), MA replies (réplique Martine Aubry).

Nouns referring to the candidates are more positive for Aubry than for Hollande who is referred to as a challenger, as a substitute, and in the expression 'except Holland --tout sauf Hollande (all except Hollande):

Hollande: deputy (député), president of the council, challenger, substitute, (candidature de 13 TERMOSTAT would be useful for teaching French as a foreign language in order to spot the most current lexical fields when describing a certain event.

substitution), Dutch (Hollandais), except Hollande Aubry: manager (patronne), rallying figure (rassembleuse) Adjectives are found describing Hollande but not Aubry; however they are unfavorable (antihollande) or they describe the theme of his campaign, e.g., he will be a 'normal candidate'; normal as adjective can be interpreted as a choice to describe Sarkozy, his political opponent, as not being a 'normal' president (because of his flashy life-style, as well as being far from ordinary citizens) or to describe Aubry as not being a usual candidate (because of her gender).

Hollande: normal (président, présidence, candidature), corrézien, anti-hollande, We can also observe that the general tone of the specificities for Hollande are more negative than for Aubry (adversaire, opposant farouche, sauf Hollande, front ani-Hollande), a hostility which does not occur in Aubry specificities.

Hollande

Our findings are corroborated by other studies. Marchand & Ratinaud (2012, 692) listed the most specific words as found in the socialist candidates speeches, finding that for Aubry out of 35 specific words, almost 40% are verbs, half of them denoting dynamism and actions such as battre 'to beat', augmenter 'to rise', arrêter 'to stop', défendre 'to defend', fermer 'shut down'; in contrast only 12 % of the most specific words identified for Hollande are verbs and they do not denote actions (falloir 'must', avoir 'to have', évoquer' to refer'). These same topoi characterized Sarkozy and Royal respectively in 2007.

After the DSK affair

However, in summer 2011 a shift in the linguistic profiles could be seen, once it was clear that Aubry and Hollande were both favourites to represent the party against the incumbent president. Despite his lack of personality and the hostility he had earlier generated (as described in the section just prior), Hollande now seemed to have become the choice of the left. While only three months earlier, Aubry was the 'rassembleuse' (see Table 7 above), in the August/ September data, the picture had changed radically: vote Hollande c'est pour éviter la fragmentation 'voting for Hollande will avoid fragmenting'; il est mieux à même de rassembler la gauche 'he is better suited (than Aubry) to unite the left'. We must assume there had been a reversal in the party discourse, as we found it reflected in the journalist word choices: Hollande was thought more 'apt' to beat Sarkozy.

Why would Hollande suddenly be better suited to the job than Aubry? Maybe this choice could be explained in part by Hollande's lead in the opinion polls? We could only conclude that, despite a positive journalistic profile, Aubry was never the favourite, neither in the polls, nor in the party. Despite his negative linguistic portrait, Hollande, in fact, actually led in the polls, and once Strauss Khan withdrew from the race, he became his party's choice.

Our data presented here suggest that female and male politicians are likely to be treated equally by their party and / or in the French press-just so long as the stakes are not high. It seems that once they get higher, such as being potentially elected president, female politicians face negative discrimination. It is also possible to conclude that because journalists are linked to political parties, they write in a way to manipulate people, so that the party's preferred candidate is chosen by the electorate. However as most studies of French political life have shown (Sineau 2010 et passim;Coulomb-Gully 2012;[START_REF] Bertini | Femmes, le pouvoir impossible[END_REF][START_REF] Gerber | Status and the gender stereotyped personality traits: Toward an integration[END_REF][START_REF] Adler | Les femmes politiques[END_REF] the 'chosen candidate' in French politics,--whether chosen by the party or by the public--is a gender issue.

Concluding remarks

Through our study we have shown how extraction of discourses markers (mainly lexical and syntactic) using NLP technologies can address the issue of gender or political favoritism in journalistic discourse. We have also shown that conclusions drawn from qualitative studies may be supplemented, refined and nuanced by working the same data using specific computer software. We have shown that SEMY (based on definitions of the digital version of Le Trésor de la langue française) was able to offer a reading based on the most salient semantic features found in the contextual environment of the names Royal, Bayrou and Sarkozy. Finally, we clarified and supplemented the linguistic profile for each candidate found with SEMY using TERMOSTAT, as it works with specificities. Even though these observational tools must always be improved, since the lists they provide require manual work, we highly recommend adding these tools when working on textual meaning, provided that the researcher has a good knowledge of the context in which the data have been produced. To summarize:

• Manual studies are essential for syntactic-semantic research, since at present they are impossible automatically; such a qualitative reading also gives researchers a comprehensive picture of their data, a prerequisite for deciding the most appropriate interpretation. ANTCONC provides the KWIC abstracts which greatly facilitate this evaluation.

• SEMY reveals recurring semantic features which cannot be detected with a superficial reading: it brings to light isotopes [START_REF] Rastier | Sémantique interprétative[END_REF], which are the semantic characteristics recurrent in a text.

• TERMOSTAT reveals how these isotopes are realized and how different they are for each candidate.

These three methodologies, therefore, appear to be complementary and to work synergistically in the analysis of textual meaning. However, to draw broader conclusions from these data, and even insofar as gender is concerned, we must examine the other dimensions of the communicative event, namely, the journalistic text, as [START_REF] Schiffrin | Other Words: Variation in Reference and Narrative[END_REF] and [START_REF] Cotter | Women's place at the Fourth Estate: Constraints on voice, text, and topic[END_REF] have underscored. These other dimensions or factors are the ethnographically situated pragmatic arrangements that obey constraints, sociocultural values, and community-of-practice conventions [START_REF] Cotter | Women's place at the Fourth Estate: Constraints on voice, text, and topic[END_REF](Cotter : 2532)). The most important in our case are the discourse practices (i.e., here the processes of text production in the French press) and the socio-cultural practices (i.e., here the French society). These must be taken into account in linguistic investigations of social power, since our focus is on the 'connection between words and the world' (Schiffrin, 2006, 333).

A discussion that considers both quantitative and qualitative analyses and the contexts of use (particularly social attitudes towards gender) will clarify the relations between 'practitioner, text, and the shared world of all participants in the discourse, and what that can say about the role of women at any point in time in a particular sociocultural context' [START_REF] Cotter | Women's place at the Fourth Estate: Constraints on voice, text, and topic[END_REF](Cotter , 2532)). We therefore recommend the use of corpus linguistic tools as a valuable method in political and social science, and believe they could be a useful prerequisite for qualitative research in the digital humanities.

  Graph 1 : KWIC abstract for Aubry's name in le Monde

Result with TERMOSTAT: NP Hollande in March-July 2011, in six newspapers

	Candidate	Frequency Specificity Spellings	Morphosyntax categ.
	primaire	248	215.29	primaire___primaires	N
	primaire socialiste	68	159.96	primaire socialiste	NAdj
	strauss-kahniens	35	113.96	strauss-kahniens	N
	candidature président normal	153 10	67.28 58.7	candidature___candidatures N président normal NAdj
	favori ex-premier secrétaire	55 9	56.29 52.5	favori___favoris ex-premier secrétaire	N NN
	de hollande	8	51.81	de hollande	N
	candidat	290	48.34	candidat___candidate	N
	candidat normal	7	48	candidat normal	NAdj
	projet socialiste	15	44.6	projet socialiste	NAdj
	investiture socialiste présidence normale	8 6	44.14 43.87	investiture socialiste présidence normale	NAdj NAdj
	sympathisants	42	41.83	sympathisants	N
	strauss-kahnien secrétaire candidat déclaré présidentiable humour corrézien député	6 170 13 13 5 150	40.6 39.66 39.42 39.42 39.32 39.11	strauss-kahnien secrétaire___secrétaires candidat déclaré présidentiable humour corrézien député___députés	N N NPPAdj N NAdj N
	sondage	97	37.69	sondage___sondages	N
	candidat de substitution	4	34.19	candidat de substitution	N
			Table1

Table 2

 2 Most frequent synonyms for the verb communiquer 'to communicate'

	montrer
	indiquer
	exposer
	signaler
	dire
	afficher
	déclarer
	découvrir
	annoncer
	manifester

Table 4 .

 4 Syntactic roles for NPs Royal and Sarkozy drawn from KWIC abstracts[START_REF] Baider | Substantive Dis-Embodiement, Syntactic Embedment. Feminism, Femininity and Gendered Discourse[END_REF]

Table 5 .

 5 Thematic role of the noun Sarkozy (251 verbs) and the noun Royal (290 verbs)

Table 6 :

 6 . They are therefore similar for all candidates.13 The most frequent items found for the NPs Hollande and Aubry in March-June 2011 in the six newspapers[START_REF] Baider | Data mining for Tracking Gender Bias: a Curse or a Blessing? The 2012 presidential duos[END_REF]

		Hollande	Aubry
	Items	Frequency	Items	Frequency
	candidat primaire président secrétaire	290 248 171 170	candidat secrétaire projet primaire	300 234 212 204
	candidature député	153 150	parti candidature	161 157
	campagne	121	socialiste	109
	parti	108	sondage	94
	sondage	97	mai	90
	soutien	83	juin	85
	projet maire	82 72	maire député	83 82

Table 7 .

 7 The most specific n-grams associated with the NPs Hollande and Aubry in March-July 2011 in the six newspapers[START_REF] Baider | Data mining for Tracking Gender Bias: a Curse or a Blessing? The 2012 presidential duos[END_REF]

	Aubry

Transitivity is analyzed to decode lack of responsibility or blame; this is carried out by taking into account the process, the participants in the process and the circumstances of the process (see the framework of Halliday

2002).

Developed at the ATILF at http://www.atilf.fr/

[START_REF] Cotter | Women's place at the Fourth Estate: Constraints on voice, text, and topic[END_REF] does not specify the size of her corpus but mentions a 'small corpus of stories" (2011, 2520).

Dominique Strauss-Kahn (known also as DSK), the likely winner of the presidential elections for the socialist party, was charged with sexual assault in May 2011 and therefore could not run in the socialist primaries.

http://olst.ling.umontreal.ca/~drouinp/termostat_web or http://termostat.ling.umontreal.ca/doc_termostat/doc_termostat_en.html,

See[START_REF] Ludovic | Statistique textuelle[END_REF] for explanation on the two criteria used to quantify the specificity of a term, one of them being the "standardized view of the frequency of the lexical units".

Other features include the most frequent compound; the most frequent morpho-syntactic pattern; etc. http://termostat.ling.umontreal.ca/doc_termostat/doc_termostat_en.html#inscription

http://www.atilf.fr/spip.php?article894. SEMY was the result of a doctoral thesis and its patent is pending. For further details please contact evelyne.jacquey@atilf.fr

http://www.crisco.unicaen.fr/des/

A tactic which is also followed by some parties when drawing up their list of candidates for elections: women are present in region where stakes are not high or where they are most likely to lose[START_REF] Sineau | La Force du nombre : femmes et démocratie présidentielle[END_REF].


Vincent Alimi
email: vincent.alimi@ensicaen.fr

Christophe Rosenberger
email: christophe.rosenberger@ensicaen.fr

Sylvain Vernois
email: sylvain.vernois@ensicaen.fr

Al Sylvain

A mobile contactless point of sale enhanced by the NFC and biometric technologies

Keywords: near field communication, mobile point of sale, match-on-card, signature dynamics

NFC transactions become very popular as they limit the time needed for a user to pay. The advantage of this technology is often seen by considering the user's point of view. In this paper, we address the use of NFC transactions for the merchant side. We propose different architectures in order to use a mobile phone as a point of sale. We compare different solutions considering some criteria such as the security assessment which is a major concern for e-payment or the facility of integration. We propose an original approach to authenticate users through the use of the touch screen of the mobile phone. The biometric authentication is based on signature dynamics (match-on-card approach) achieving a usable solution for this application.

Introduction

Point of sales (POSs) are the electronic devices that allow a merchant to process a payment transaction either with the magnetic stripe card (e.g., in the USA) or the chip smart card (e.g., in Europe) of a cardholder. Since a few years, contactless payment smart cards have made their appearance as well as contactless POSs to handle those specific form factors. Some of the existing solutions are mobile and allow the merchant to accept contactless payment somewhere else than his shop such as itinerant merchants, taxi drivers or commercial airplanes staff. In today's world, 'mobility' has taken an important place in users' life. Nowadays, mobile phones are used as the main vector and the convergence point of mobile services such as internet browsing, e-mails reading, TV, etc. Thus, the mobile phone has become an electronic 'Swiss Army Knife'.

Turning a mobile phone into a secure contactless mobile POS is a topical question. Ingenico ® has been a pioneer by delivering such a solution with 'iSMP' (Ingenico, 2011). Ingenico ® 's iSMP is a certified sleeve on which an iPhone or iPod is connected and that turns it into a contactless mobile POS. It has the advantage to comply with the security standards but has some drawbacks. Indeed, it is available only on Apple's devices and it uses the mobile just like a modem.

In this paper, we present three architectures based on the NFC technology to turn a mobile phone into a mobile POS accepting contactless payments. After giving a technical background on POSs and the NFC technology, we study the related works in the literature and in the field. We then expose and discuss the proposed architectures and explain why we consider the solution combining the baseband processor and the secure element (SE) is the most suitable. Then, we finish with a proposition of a match-on-card signature verification method.

Point of sale

A POS is an electronic device located at a merchant's place and acting as a point of interaction with the banking system. It handles a payment transaction using either a magnetic stripe card by acquiring the data contained in the magnetic track or with a smart card by sending and receiving application protocol data units (APDU) commands as defined in the ISO7816 standard.

As an important link in the payment chain, the POS must be a very secure device. Therefore, it is tamper-resistant and resistant to many physical and software attacks in order to comply to Payment Card Industry PIN Transaction Security (PCI PTS) (Payment Card Industry, 2011) security standards. For example, the payment applications -called payments kernels -are hosted in a secure memory and the cryptographic keys and certificates are hosted in a secure non-volatile memory or in a secure smart card called secure access module (SAM).

Depending on the country, the card and the terminal, the transaction can be processed offline or online, i.e., by connecting or not to the issuing bank. In case of offline payments, the POS is responsible of checking the integrity of the transaction data with protocols based on asymmetric keys. In case of online payments, this verification is processed by the bank thanks to hardware security modules (HSM).

In the following sections, we would like to give to the readers a brief technical background on what a POS and the NFC are.

The RFID and NFC technology

In [START_REF] Finkenzeller | RFID Handbook: Fundamentals and Applications in Contactless Smart Cards, Radio Frequency Identification and Near-Field Communication[END_REF], the radio frequency identification technology (RFID) is presented as "a contactless transfer of data between the data-carrying device and its reader (...) The power required to operate the electronic data-carrying device would also be transferred from the reader using contactless technology". It operates at different frequencies ranging from 135 kHz to 24 GHz. One of the most known application of RFID systems is the coupling of identification smart cards and is described in several ISO standards such as ISO 14443 (ISO/IEC, 2008) and ISO 15693 (ISO/IEC, 2010). As an illustration, ISO 14443 is used for contactless payment and transit smart cards and ISO 15693 for contactless access control smart cards.

Near field communication is a proximity communication technology based on ISO 14443, and is standardised in ISO 18092 (ISO/IEC, 2004). It operates at 13.56 MHz and allows data transfer up to 424 Kbits/second. NFC devices support three operating modes:

• Reader/writer mode (proximity coupling device, PCD): Operating in this mode, a NFC device can read and alter data stored on a passive tag. Such tags can be found on smart posters, e.g., allowing the user to retrieve additional information by reading the tag with the NFC device.

• Card emulation mode (proximity induce coupling card, PICC): In this mode, a NFC device can emulate a proximity smart card (ISO14443). A reader cannot distinguish a NFC device in emulation mode from a smart card.

• Peer-to-peer mode: The NFC peer-to-peer mode (ISO18092) enables two NFC devices to exchange, through a bidirectional connection, data such as contacts, vCards, pictures, etc.

The use of the different NFC modes has been largely experienced in trials such as access control, bus ticketing and parking payment within the European SmartTouch project [START_REF] Ailisto | Experiences from interaction design for NFC applications[END_REF]). An NFC-enabled device consists of the following logical components: the NFC controller and, optionally, a secure smart card referred to as the SE. They are illustrated in Figure 1. The NFC controller, also referred to as contactless frontend (CLF) within ETSI, is responsible for the analogue/digital conversion of the signals transferred over the proximity connection. The SE, only used in card emulation mode, is a dynamic environment where applications are downloaded, personalised, managed and removed independently of each other with different life cycles. Four main implementation options for the SE have been identified as promising alternatives at this point [START_REF] Emvco | Emv mobile contactless payment technical issues and position paper[END_REF]: embedded hardware, UICC, removable hardware, SE in the baseband processor (also called application processor).

It is very likely that NFC will be one of the next step forward for the mobile phone manufacturers. It is expected that the customers can pay with their mobiles. Thus, the POSs will have to evolve in order to adapt to this new next form factor. In the following sections, we present a state-of-the-art of the contactless POS solutions.

Related research and technology

In this section, we present works in the state-of-the-art on contactless and mobile payment research. We study first the literature, then the industrial field. We show that the academic research on the topic is rare and discuss the different findings. Prior to this, we would like to mention that as contactless and mobile payments are based on the same technology, we include both of them in the study. Furthermore, as noticed by [START_REF] Ondrus | An assessment of NFC for future mobile payment systems[END_REF], there are few papers evaluating the potential of NFC and they provide a very descriptive approach that limits the evaluation [START_REF] Chen | Short-range wireless technologies with mobile payments systems[END_REF][START_REF] Zmijewska | Evaluating wireless technologies in mobile payments: a customer centric approach[END_REF]. This can be explained by the recent emergence of the contactless and mobile payment research and the fact that POSs are often considered as a highly secure piece of hardware on the merchant side and strictly controlled by banks. Thus, it is not likely to be subject to research activities. Among the few papers dealing with this topic we can quote [START_REF] Resatsch | Mobile sales assistant: NFC for retailers[END_REF] in which a mobile phone is turned into a sales assistant, displaying information about a product when tapping its RFID tag. Nevertheless, this scenario, i.e., payment, requires a more robust architecture as it deals with very sensitive data. [START_REF] Veijalainen | Transaction management for m-commerce at a mobile terminal[END_REF] study the use case of a payment transaction in a taxi. The user holds a personal trusted device to return the credit card details to the card terminal over a wireless link (Bluetooth, infrared or RFID). The latter sends the payment data to the payment scheme in order to get the transaction confirmation. In this use case, the communication between the devices does not especially rely on the NFC but the authors highlight the need for security, privacy and trust of such a solution.

Contactless payment terminals in the industry

The contactless POSs found in the industry come in multiple forms. One can find unattended contactless POS, contactless payment readers to be connected to an existing POS or fully integrated contactless POS. In addition, they can implement a supplementary feature to support mobile payment. Unattended contactless POS can be found on gasoline dispensers, toll road or vendor machines. They deal most of the time with small amount transactions and increase the speed and convenience of the purchase for the consumer.

Contactless payment readers or targets are external devices connected to an existing POS or electronic cash register (ECR) that handle the radio-frequency dialog and the contactless payment transaction. At the end of the transaction, it sends to the associated POS or ECR the data to be sent on the clearing networks. Among available products, one can quote the VivoPay ® solutions.

Fully integrated contactless POS are the last generation of POSs. They embed in the same device all hardware and software to handle contactless payments (contactless antenna and micro-controller, contactless payment applications, ...).

Motivation

The aforementioned solutions present common characteristics such as the ease, speed and convenience of the transaction. Most of them are countertop solutions, i.e., intended to be used in shops. A very few of them are intended to be mobile, for itinerant merchants for example. This can be explained by the necessity to be connected to the bank (depending on the country) and the extra cost it would imply. Another point that needs to be revealed is the lack on the market of POS capable of handling NFC mobile payments, i.e., where the contactless card is emulated by a mobile phone. Those payments differ from standard contactless payments by the fact that, very often, the payment functionality of the mobile would be protected by a passcode or personal code. Thus, this implies an additional interaction with the user to inform him the payment is refused and that he should enter his passcode on his mobile.

The motivations to design mobile NFC POS solutions are the following:

• allows accepting contactless and mobile payments

• suitable for itinerant and outdoor merchants

• can coexist on the same device with other mobile services

• use the existing data plan subscription to connect to the bank or payment gateway

• allows a rich user interface by taking advantage of the mobile device display

• allows a variety of added-value services such as dematerialising the receipt or adding geolocation-based information.

In the next section, we propose three architectures turning a mobile into a mobile contactless POS thanks to the NFC technology. Then, we compare them with objective criteria such as the security offered by the solution and the integration effort for the device manufacturer.

Proposed architectures

In this section, we detail three possible architectures for a mobile contactless POS taking advantage of the NFC technology.

Everything in an external device

This architecture is shown in Figure 3(a). A SE, i.e., a highly secure smart card (e.g., EAL4+ security level), is embedded in a small device that is connected to the mobile's dock. This SE hosts the payment kernels, a software SAM, a toolbox of cryptographic facilities and a dedicated processor. The device is linked to the NFC controller via a digital link and the NFC controller can be accessed from the baseband processor with the classical mechanisms [e.g., JSR 257 (Java Community Process, 2009)]. For the visual interface with the users, i.e., the merchant and the customer, a UI application is ran from the baseband and access the device via an application programming interface (API). When a smart card is detected in the RFID field, the concerned payment kernel (i.e., Visa © , MasterCard © , JCB © or other) communicates with the card and process the payment transaction. The payment transaction data is then sent to the host application for sending an authorisation query over the network. The UI application is used to display the details of the transaction and eventually captures the cardholder signature or PIN code.

Payment kernels in the baseband and SAM in the SE

In this architecture, the payment kernels and the SAM are placed in two different locations [cf. Figure 3(b)]. The payment kernels are located in the baseband processor while the SAM is securely hosted by the SE along with some cryptographic functions.

The SAM is a piece of software code in the SE that is accessed by the payment kernels through an API. It contains the issuer's public keys to validate the card certificates and eventually some symmetric DES keys to secure the communication over the mobile network operator (MNO) network. The payment kernels and the API are built over a trusted execution environment (TEE) [START_REF] Aarts | On-line signature verification with hidden Markov models[END_REF]). TEE's main goal is to offer a two world-based platform: a secure world in which execution of code, access to I/O and devices such as display and keyboard are secured; and the 'normal' world in which applications run in the standard way. Those last can access secure applications, called services, via a secure channel between the two worlds. When a card is detected in the field, the payment kernel is informed by the NFC controller. Then, the payment kernel handles the transaction by sending commands from the baseband to the card passing through the NFC controller. This is done via mechanisms such as JSR 257 in Java-based mobiles. The UI application is placed in the normal world of the TEE, except for 2 operations: the cardholder PIN code entry or signature capture and the confirmation of the amount. Indeed, two of the attacks that are dread in a mobile payment environment are the stealing of the PIN code (e.g., by a key logger) and the falsification of the displayed amount (e.g., display a 10 euros amount while the transaction is processed for 100 euros). For these reasons, those two operations are based on subroutines located in the secure world. This allows what we will call 'Secure mobile PIN' and 'What you see is what you pay'. To ensure of the UI application integrity, its code is hashed and the result is stored in the SE. Every time the application is launched, a subroutine is called from the TEE's secure world and checks the integrity by comparing the computed hash and the one stored.

Everything in the SE

This approach is similar to the first one except that the components are not embedded in an external device but in the SE of the mobile. It is illustrated in Figure 3(c). The payment kernels are securely hosted and executed from the SE as well as the SAM. It allows taking benefits of existing SE architectures such those relying on a GlobalPlatform base [START_REF] Dahlberg | Past, present and future of mobile payments research: a literature review[END_REF]. The payment kernels and the SAM are located in a security domain that keeps them safe from any altering attempts. When a smart card is detected in the field, the SE handles the payment transaction and sends events to the baseband processor to update the display with transaction details.

Comparative study

In this section, we discuss the three proposed architectures, compare them with objective criteria and summarise their benefits and limitations. The considered criteria are: the offered security level, the target of security certification and the integration effort needed to integrate the solution in existing devices. Each criteria is rated from 1 to 4 according to the analysis done below.

Everything in an external device

• Security: this solution is very secure as the components are hosted outside of the mobile in a certified add-on. It would obtain a pretty good level of certification as the target of evaluation (TOE) is simple. 'We assign the scores of 4 for the offered security and 4 for the certification level'.

• Integration: this solution suffers from difficulties of integration. Indeed, until all mobile phones have the same dock, the device has to be implemented for all models. Furthermore, some additional APIs have to be added to the mobile software stack as well as some hardware modifications to enable the communication between the NFC controller and the SE in the external device. 'We assign the score of 1'.

• Analysis: this solution allows to turn a mobile phone into an NFC mobile POS just by plugging an external add-on. It requires an integration effort as it uses a proprietary connector and proprietary access APIs.

Baseband and SE

• Security: this solution inherits the security of the highly secure TEE and SE. The certification seems to be a difficult point as it would consist in certifying the operating system of the mobile. Some initiatives such as aggregation certification are also under investigation to certify complex targets such as operating systems (GlobalPlatform, 2011a). 'We assign the scores of 3 for the offered security and 3 for the certification level and maturity of the solution'.

• Integration: the TEE is a very promising secure concept but suffers from a lack of both integration efforts by manufacturers and standardisation efforts by the industry. Regarding the latter, there is a current initiative at GlobalPlatform (2011b) to define an API to access secure services hosted by the TEE, the interface between the TEE and the SE and the secure interface with the keyboard and display. 'We assign the score of 2.5'.

• Analysis: combining a trusted operating system and a secure chip, this solution offers a high level of confidence. It should help the adoption of mobile payment in general and the entry of a PIN code on a mobile device. Nevertheless, as it is not mature yet it is not a reliable solution in the short term. But, it is likely to be one of the most reliable solution in the long-term.

Everything in the SE

• Security: in this solution, the components are hosted by the SE, a highly secure by design piece of hardware and software. Thus, the payment kernels and SAM are placed in the most safe place in the mobile and inherits its security properties. 'We assign the scores of 4 for the offered security and 2.5 for the certification level'.

• Integration: this approach is very secure but implies a lot of work on integration of the SE-NFC controller link. Indeed, the SE is designed to emulate a smart card. In this mode, it is asked to emulate a terminal, i.e., be the originator of the transaction and to send the commands to the card instead of treating incoming commands, do the card-side processing and respond. This requires to completely change the processing of both the NFC controller and the SE. Another concern is the transaction timing. Indeed, SEs are optimised for performing cryptographic operations such as signing and hashing but not for the inverse operations (signature verification, hash verification). 'We assign the score of 1'.

• Analysis: with a further integration effort, this solution could add a great added value for the security of the PIN entry and the display of the transaction amount. Indeed, as the SE is a highly secure and certified component, it could be part of the design of new generation secure mobile phones and help also the adoption of the NFC technology.

Synthesis

Table 1 compares the three architectures according to the following criteria: the ease of integration in mobile phones, the security of the solution and the ease/feasibility of the certification. In the latter, we include the certification by the PCI security standards. The PCI standards take care of the appropriate use and storage of the cardholder data [as per Payment Application Data Security Standard, PA-DSS (Payment Card Industry, 2012)] as well as the security of the PIN entry [as per PCI PTS (Payment Card Industry, 2011)].

In the proposed solutions, whether a PIN is to be entered by the user, the PCI PTS standard apply. It defines the requirements to ensure the logical and physical security of the POS and the protection of the data between the input component (in our case the mobile keyboard or touch screen) and the secure controller of the device (in our case the SE). An overall mark summarises the evaluation. The marks range from to (the ✬ symbol represents a half-star) and are assigned according to the aforementioned discussion items.

Conclusions

Table 1 shows that the integration of the three solutions suffer either from a software or from a hardware standpoint. Indeed, the TEE is not a mature technology yet and the SE found in NFC-enabled devices has not been designed to work as a 'Master'. It also shows that the three solutions are very secure but they differ in the certification level they can achieve. We observe that the two 'monolithic' solutions obtain a high confidence for the certification while the 'combined' solution suffers from difficulties in the OS certification.

Nevertheless, these difficulties are only software related. Indeed, while there exist hardware challenges for the integration of the two monolithic solutions that are to be solved by the manufacturers, the TEE and its certification mobilise of lot of efforts in the standardisation bodies. It is estimated that in the upcoming years (GlobalPlatform, 2011b), a reliable and stable solution will have been designed, published and implemented. Thus, if we refer back to Table 1, we would assign the score of 4 for the integration and the certification of the solution. The combined solution would then become the best solution of the three exposed in this paper.

In the motivations section, we mentioned the ability of using the mobile device display to offer a rich user interface. More and more, the devices on market are equipped with touch-sensitive screens and allow a richer interface with the user. Indeed, in our case, the touch-sensitive screen can be used to capture the cardholder's signature and dematerialise the receipt usually printed. In the next section, we expose a method to verify a signature captured on a touch-sensitive screen in order to enforce the security of the transaction.

A match-on-card signature verification algorithm

In order to verify if the user is the real owner of the smart card, we need to process an additional authentication step. The requirements for a contacless face to face payment are:

1 the authenticator needs to be difficult to obtain or to duplicate by an impostor 2 the verification must be fast 3 the authentication solution must be as simple as possible for the user.

Among the different solutions in the state-of-the-art, we make the choice of the authentication method for the proposed application in the next section.

Authentication solutions

The authentication process can be based on a combination of one or more authentication factors. The four (widely recognised) factors to authenticate humans are:

• Something the user knows: a password, a pass-phrase, a PIN code, the maiden name of his mother…

• Something the user owns: a USB token, a phone, a smart card, a software token, a navigator cookie…

• Something that qualifies the user: a fingerprint, a DNA fragment, a voice pattern, hand geometry…

• Something the user can do: a signature, a gesture…

For an e-payment application, we suppose that the user holds the smart card. Another authentication factor is always used for face to face payments, the most common solutions are: the knowledge of a PIN code or the ability to make the same signature than the one printed at the back of the smart card. The problem is that these authentication methods are not sufficient to guarantee the identity of the user. It is not a difficult task to obtain the PIN code of another user. Moreover, with training, it is rather easy to be able to impersonate the signature of somebody (as the verification is done visually). To overcome all these drawbacks, in this paper, we propose to use a biometric-based solution.

Biometrics is associated to the authentication factors based on what users are or how they do things. The main advantage of biometric systems is the strongest relationship between the authenticator and the associated user. Other user authentication approaches are more related to machine authentication. It is so a priori more difficult to steal or copy the biometric template of an individual compared to a PIN code as for example. The user authentication generally generates some errors that must be of course minimised, that constitutes the main drawback of the authentication methods based on biometrics. There are three categories of biometric modalities: biological (DNA, blood...), behavioural (signature dynamics, keystroke dynamics, voice...) and morphological (fingerprint, face, hand veins...). The most used biometric modality is the fingerprint because of its efficiency and the cost of the sensor. In this paper, we propose to use signature dynamics for many reasons:

• easy for an user to sign

• quick verification

• easy to capture on a smart phone with a touch screen • difficult to forge the signature dynamics of an user (way of signing).

In the next section, we present a state-of-the-art on signature dynamics to choose the best solution to embed in the proposed POS.

State-of-the-art in signature dynamics

In our application, we suppose having at each time t, the location of the pencil in the touch screen represented by a vector (x t , y t ), t = 1: N (N depending of the complexity of the user's signature). Based of this vector, we can measure different features to generate user's template (enrolment step) and to realise the verification step. The problem of the signature dynamics verification can be resolved by computing a complex distance between the reference signature and the capture one based on the features computed on the raw data.

There are two main approaches for the verification of the signature dynamics. The first one is based on a global computation taking into account different features of the signature dynamics such as the average speed, the total duration … [START_REF] Fierrez-Aguilar | An online signature verification system based on fusion of local and global information[END_REF][START_REF] Ketabdar | Global feature selection for on-line signature verification[END_REF][START_REF] Yanikoglu | Online signature verification using Fourier descriptors[END_REF]. This category provides quite poor results. The second category uses a local information for the comparison of two signature dynamics. Some methods compute a descriptor on each acquired point (x t , y t ) [START_REF] Jain | On-line signature verification[END_REF][START_REF] Henniger | Biometric user authentication on smart cards by means of handwritten signatures[END_REF][START_REF] Kholmatov | Identity authentication using improved online signature verification method[END_REF][START_REF] Van | On using the viterbi path along with HMM likelihood information for on-line signature verification[END_REF]. Another possibility is to compute a descriptor on specific points (where the speed is higher as for example) [START_REF] Hao | Online signature verification using a new extreme points warping technique[END_REF]. The last solution consists in computing some descriptors on each interval on the signature dynamics [START_REF] Aarts | On-line signature verification with hidden Markov models[END_REF].

One of the most efficient solution [especially when only two measures (x t , y t ) are used (Garcia-Salicetti and Houmani, 2009)] is based on the elastic distance [START_REF] Martinez-Diaz | Signature Features[END_REF]. We have chosen this approach as it gives good results and the verification is quick. First, the (x t , y t ) signals of the signature dynamics can be resampled in order to provide equidistant spacing between points (considering time). Two features are extracted at each point in the signature namely δ x and δ y , these features correspond to the change in the x direction and y direction. The feature values are finally normalised. The matching algorithm is based on the string matching technique called dynamic time warping (DTW). The performance of this algorithm has been evaluated on different benchmarks (such as MCYT-100). The equal error rate (EER) value is around 3% meaning that for the compromise configuration (specific setting of the biometric system), 3% of impostors are accepted and 3% of genuine are rejected. As this authentication method is additional to the belonging of the smart card, this is a correct result. We think also this result is much better than a visual verification and more convenient for the merchant. As illustration, Figure 4 presents an example of comparison of two signature dynamics of a genuine user.

Implementation

We describe in this section the implementation on the signature dynamics verification. We distinguish two steps:

• Enrolment: The biometric template of an individual is stored in its smart card. It consists in a vector of dimension 2N where N is the temporal sampling number of the signature dynamics. In our studies, 50 is a good value. In this case, the storage of its personal signature R = {(x t , y t ) t = 1:50} costs 200 octets (2 octets per value x or y).

• Verification: For the authentication process, the user is asked to sign on the touch screen of the mobile phone considered here as a POS. Once the signature dynamics captured (a vector of 50 values C = {(x t , y t ) t = 1:50}), the POS sends to the smart card through a contactless transaction an encrypted message containing the biometric data and a random challenge. The encryption is realised by using the classical RSA algorithm with the public key of the smart card (embedded in its certificate). The smart card decrypts the message and compares C and R with the verification method described in the previous section (match-on-card). The smart card sends back an encrypted message with its private key containing the result of the verification with the challenge previously transmitted by the POS. The POS decrypts the previous message using the public key of the smart card and verifies the challenge (check if it is the same than the one transmitted). The verification result is printed on the screen of the POS. This ends the authentication process.

A proof of concept software has been developed on a Windows TM Platform and is shown in Figure 5. We have implemented a tablet version of the signature dynamics authentication scheme. It is very fast (the answer is given in less than 1 second) and meets operational constraints. We have implemented a low cost version based on correlation computation between signals that can definitely be used on a SE (such as a SIM card).

Discussion

We think this solution is very usable for many reasons:

• The security is achieved through classical cryptography. An attacker cannot retrieve the signature dynamics of another user as it is encrypted. The replay attack is not possible thanks to the use of a challenge by the POS.

• The processing time is low as it consists only on computing a distance between two vectors of integers.

• It is very convenient for the user as anybody is used to sign documents.

Conclusions

We presented in this paper three secure architectures to implement a mobile contactless POS solution that are adapted to the contactless and mobile payment requirements. The three proposed architectures present a very good level of security but require a more or less important work of integration. As it would allow to securely key a PIN code and displays the transaction information, we think that the solution combining a TEE in the Baseband and the SE is the most reliable in the long term. It should help the adoption of mobile payment and the user trust in this technology. We also presented a match-on-card signature verification method. This solution, that dematerialises the usual paper signature, has the advantages to be secure, low-time processing and convenient for both the user and the merchant. Furthermore, it is applicable to the three architectures exposed in this paper.

Figure 1

 1 Figure 1 Architecture of NFC integrated in a mobile device (see online version for colours)

Figure 2

 2 Figure 2 Examples of contactless readers and POSs, (a) VivoPay ® contactless reader (b) unattended POS (c) integrated POS (Ingenico ® i3070) (see online version for colours)

Figure 3

 3 Figure 3 Proposed architectures, (a) payment kernels and SAM in an external device, (b) payment kernels in the baseband and SAM in the SE, (c) everything in the SE (see online version for colours)

Figure 4

 4 Figure 4 Example of two signatures from the same person (see online version for colours)

Figure 5

 5 Figure 5 Signature verification proof of concept (see online version for colours)

Table 1

 1 Comparison of the proposed mobile POS architectures

		Integration	Security	Certification	Overall
	Secure element			✬	✬
	External device
	BB and SE	✬