Lucie Ménard
email: menard.lucie@uqam.ca

Jean-Luc Schwartz

Perceptuo-motor biases in the perceptual organization of the height feature in French vowels

Keywords: 43, 71, An, 43, 71, Es

, we investigated the implementation of vocal height contrasts along the F1 dimension in French speakers. In this paper, we present results from perceptual identification tests performed by twelve participants who took part in the production experiment reported in the earlier paper. For each subject, stimuli presented in the identification test were synthesized in two different vowel spaces, corresponding to two different vocal tract lengths. The results showed that first, the perceived French vowels belonging to similar height degrees were aligned on stable F1 values, independent of place of articulation and roundedness, as was the case for produced vowels. Second, the produced F1 distances between height degrees correlated with the perceived F1 distances. This suggests that there is a link between perceptual and motor phonemic prototypes in the human brain. The results are discussed using the framework of the Perception for Action Control (PACT) theory, in which speech units are considered to be gestures shaped by perceptual processes.

Introduction

The rigorous debate between proponents of the auditory and motor theories of speech perception continues (see e.g. [START_REF] Diehl | Speech perception[END_REF] vs. [START_REF] Galantucci | The motor theory of speech perception reviewed[END_REF]), particularly in light of recent neurophysiologic evidence coming from the literature on perceptuo-motor interactions in the human brain [START_REF] Rizzolatti | The mirror-neuron system[END_REF][START_REF] Hickok | Dorsal and ventral streams: A framework for understanding aspects of the functional anatomy of language[END_REF][START_REF] Hickok | The cortical organization of speech processing[END_REF][START_REF] Lotto | Reflections on mirror neurons and speech perception[END_REF][START_REF] Scott | A little more conversation, a little less action-candidate roles for the motor cortex in speech perception[END_REF][START_REF] Pulvermuller | Active perception: sensorimotor circuits as a cortical basis for language[END_REF] drawing arguments both for and against motor theories.

Major arguments about the potential role of motor knowledge on speech perception generally come from experiments assessing how the fact that a listener knows something about coarticulation in speech helps her or him better process speech sounds in order to extract invariant features (e.g. [START_REF] Liberman | The motor theory of speech production revised[END_REF][START_REF] Perkell | Invariance and variability in speech processes[END_REF][START_REF] Fowler | An event approach to the study of speech perception from a directrealistic perspective[END_REF][START_REF] Fowler | Listeners do hear sounds, not tongues[END_REF][START_REF] Schwartz | Filling the perceptuo-motor gap[END_REF]). Another more recent set of arguments concerns the possibility of modulating the results of a speech perception task by a perturbation applied to the speech production system, e.g. by transcranial magnetic stimulation [START_REF] Ausilio | The motor somatotopy of speech perception[END_REF][START_REF] Sato | A mediating role of the premotor cortex in phoneme segmentation[END_REF] or used-induced motor-plasticity [START_REF] Sato | Articulatory bias in speech perception: evidence from use-induced motor plasticity[END_REF].

In this paper, we address another type of phenomenon that likely involves speech perceptuo-motor coupling in the human brain. This concerns the possibility that correlations may exist between the way the repertoire of phonemic units for a given subject is implemented in speech perception and speech production.

Relationships between the perceptual and motor phonemic repertoires

If there is indeed a link between speech perception and action in the human brain, this should result in relationships between the way phonemic repertoires are shaped in speech perception and speech production. Currently, direct evidence for such links between perceptual and motor repertoires is scarce. Of course, inter-linguistic differences can lead to variations of both motor and perceptual systems, but this produces an apparent link that is the consequence of only one external cause: the fact that the linguistic environment varies according to the subject's language (e.g. between French and Italian subjects), producing differences in both perception and production (see e.g. [START_REF] Yang | A study on the production-perception link of English vowels produced by native and non-native speakers[END_REF]).

Thirty years ago, a series of studies attempted to demonstrate that subtle differences in speech production and speech perception within a coherent linguistic environment could lead to intra-subject correlations, suggesting a link between idiosyncrasies in the perceptual and motor repertories. Bell-Berti et al. [START_REF] Bell-Berti | Some relationships between speech production and perception[END_REF], quoted in Galantucci et al. [START_REF] Galantucci | The motor theory of speech perception reviewed[END_REF], reported differences between subjects in the perception of the [i] versus [I] contrast in American English, which seemed to be linked to differences in the articulatory implementation of this contrast, related more with tongue height in one case and tongue tension in the other case. In the same vein, Fox [START_REF] Fox | Individual variation in the perception of vowels: implications for a perception-production link[END_REF] studied perceptual structures of the vowel space in American English through a multidimensional scaling analysis of estimated auditory distances between vowel pairs. He then attempted to correlate individual differences in the use of estimated perceptual dimensions with characteristics of the vowel space in speech production by the same speakers. He claimed to have found some correlations. However, the perceptuo-motor link was not clear, especially since the statistical analysis may have included some artifacts, given the large number of attempted correlations between variables.

During the same period, studies on selective adaptation also provided evidence for dynamic links between motor and perceptual representations (see e.g. [START_REF] Cooper | Feature processing in the perception and production of speech[END_REF][START_REF] Cooper | Speech perception and production[END_REF][START_REF] Jamieson | The adaptation of produced voice-onset time[END_REF]). More recently, a series of studies by Perkell and colleagues showed how perceptual abilities can shape production strategies for vowels [START_REF] Perkell | The distinctness of speakers' productions of vowel contrasts is related to their discrimination of contrasts[END_REF] or fricatives [START_REF] Perkell | The distinctness of speakers' /s/-/ʃ/ contrast is related to their auditory discrimination and use of an articulatory saturation effect[END_REF], and can adapt to feedback perturbation [START_REF] Villacorta | Sensorimotor adaptation to feedback perturbations of vowel acoustics and its relation to perception[END_REF]. On the other hand, more relevant for the present discussion, Shiller et al. [START_REF] Shiller | Perceptual recalibration of speech sounds following motor learning[END_REF] recently showed how a perturbation of the production of the [s]- [ʃ] contrast resulted in after-effects with consequences not only on production but also on perception, leading to a boundary shift in the same direction as the one induced on production (see Nasir and Ostry [START_REF] Nasir | Auditory plasticity and speech motor learning[END_REF] for similar results with both production and perception after-effects following perturbations of the somato-sensory feedback in vowel production).

Such evidence for a dynamic coupling between perceptual and motor behaviors suggests that there should indeed exist some hard-wired coupling between the way phonemic units are represented in the perceptual and motor systems of speech. In order to derive clear-cut evidence for a link between perceptual and motor repertoires in a single subject, the present paper capitalizes on an idiosyncratic effect that we recently discovered related to the production of height contrasts in French vowels.

F1-series as a paradigm for investigating perceptuo-motor links

In a previous paper [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF] we investigated the organization of the height feature in French vowels along the F1 dimension. Twenty-seven French speakers (children around 4 years old, children around 8 years old, and adults) from two dialect regions (France and Canada) were recorded, to generate significant between-subject variability. Each speaker produced repetitions of the ten sustained, isolated French oral vowels /i y u e ø o ɛ oe ɔ a/.

Acoustic analyses showed considerable between-subject variability in the relative positions of the vowels within the vowel space. However, speakers tended to produce vowels along a given height degree with a stable F1 value depending on the speaker, but independent of place of articulation and roundedness. Interestingly, this resulted in clear significant differences in the implementation of height contrasts, with some subjects displaying a strong proximity between high (e.g. [i]) and mid-high (e.g. [e]) vowels, while others displayed a strong proximity between mid-high and mid-low (e.g. [ɛ]) vowels, and still others displayed a strong proximity between mid-low and low (e. g.

[a]) vowels. Simulations with an articulatory model of the vocal tract (that we will describe later), the Variable Linear Articulatory Model (VLAM), showed that a stable F1 value was related to a stable tongue height. Hence it appeared that each subject displayed her or his own idiosyncratic choice in the precise way the vowel height features were implemented, with a speaker-specific distribution of F1 values inside the vowel triangle.

An individual speaker's idiosyncrasy leading to within-speaker stable F1 values for a given vowel height degree, along with large between-speaker variability of such F1 values, could provide an experimental paradigm for assessing perceptuo-motor links in vowel processing and categorization. The question raised by our recent experiments concerns the role played by this idiosyncrasy in vowel perception processes: Would a subject display as a listener the same type of F1 series as he or she did as a speaker? Moreover, if this was the case, would there be a relationship between variability in perception and in production, with a similar series of biases in both perceptual and motor vowel prototypes? Finally, how would vocal tract variability intervene in this process? If there was an "F1-series" effect in perception, the distribution of F1 values according to vowel height would be similar for various vocal tract sizes for a given listener. These questions and hypotheses led to the present experiments in which we investigated the organization of the perceived height in French vowels for various listeners-with synthetic stimuli corresponding to various vocal tract sizes and speaker ages-in relation to the listener's own vowel production as a speaker of that language.

Objectives

We aimed to establish perceptual regions for the French oral vowels, for French listeners ranging in age from 4 years old to adulthood, using stimuli corresponding to two different vocal tract sizes (child and adult). This method would allow us to present listeners with variable formant and F0 values. First, we aimed to study the distribution of mean F1 values for each vowel category to test for possible F1 stability at a given height.

Second, we aimed to compare the distribution of F1 values for each vowel category from one vocal tract size to the other for each subject. Finally, we aimed to assess the relationships between production and perception concerning the organization of height degrees along F1.

Method

Participants

The twelve native speakers of Continental French (the CO corpus) who participated in the production study reported by Ménard et al. [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF] also participated in the perceptual tests described here. The participants were grouped into three age groups: 4year-olds (two females), 8-year-olds (two males and two females) and adults (three males and three females). The average ages of the three groups were: 4 years, 10 months (from 3 years, 10 months to 5 years, 10 months); 8 years, 1 month (from 6 years, 2 months to 9 years, 11 months), and 25 years (from 18 to 39 years). These three groups will be referred to as the 4-year-old group, the 8-year-old group, and the adult group. This grouping into three age categories was of course not very accurate, with for example, a small difference in age between the oldest child in the 4-year-old group and the youngest one in the 8year-old group. However, this very "rough" age grouping did not have strong impact on the experimental paradigm, as discussed later in this section and in Section 3.

None of the speakers reported any history of auditory or articulatory disability.

The screening procedure consisted of (1) a brief conversation with the experimenter and a speech language pathologist, (2) a 20-dB pure-tone screening at 500, 1000, 2000, 4000, and 8000 Hz, and (3) for children, a brief developmental test to detect speech production disabilities [START_REF] Chevrie-Muller | Plaza: Les nouvelles épreuves pour l'examen du langage [New tasks for language evaluation[END_REF].

Stimuli

Each subject participated in an auditory identification test. The stimuli for the perceptual experiment were 5-formant vowels that were synthesized with the Variable Linear Articulatory Model (VLAM) [START_REF] Boë | Modélisation de la croissance du conduit vocal. Espace vocalique des nouveau-nés et des adultes. Conséquences pour l'ontogenese et la phylogenese[END_REF][START_REF] Boë | Modelling the growth of the vocal tract vowel spaces of newly-born infants and adults: consequences for ontogenesis and phylogenesis[END_REF], an articulatory-to-acoustic model of the vocal tract based on Maeda's adult model [START_REF] Maeda | An articulatory model of the tongue based on a statistical analysis[END_REF]. This model integrates data on the longitudinal growth of the vocal tract [START_REF] Goldstein | An articulatory model for the vocal tracts of growing children[END_REF] and has been used previously in phonetic studies [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF][START_REF] Ménard | Auditory normalization of French vowels synthesized by an articulatory model simulating growth from birth to adulthood[END_REF][START_REF] Ménard | Role of vocal tract morphology in speech development: perceptual targets and sensori-motor maps for synthesized French vowels from birth to adulthood[END_REF][START_REF] Ménard | Articulatory-acoustic relationships during vocal tract growth for French vowels: analysis of real data and simulations with an articulatory model[END_REF]. From an articulatory configuration controlled by seven parameters (lip protrusion, lip height, tongue tip position, tongue body position, tongue dorsum position, jaw height, and larynx height), VLAM generates realistic 5-formant vowels corresponding to vocal tract length and configuration representative of speakers from birth to adulthood.

Each subject was presented with two series of synthesized vowel stimuli, one series generated on a vocal tract simulating an age (and hence a vocal tract length) close to the subject's own age-to assess perceptuo-motor idiosyncrasies in optimal conditions-and the other series generated on a vocal tract from a very different age (and vocal tract length), to assess normalization processes.

Adult stimuli

For the first dataset, the adult stimuli, all the stimuli were generated in VLAM, based on vowels spoken by a simulated 21-year-old with a total vocal tract length of 17.45 cm and an F0 value of 112 Hz. Using VLAM, we generated the maximal vowel space (MVS) [START_REF] Boë | Maximal Vowel Space. 1 st European Conference on Speech Communication and Technology (Eurospeech)[END_REF], as described previously [START_REF] Ménard | Auditory normalization of French vowels synthesized by an articulatory model simulating growth from birth to adulthood[END_REF][START_REF] Ménard | Role of vocal tract morphology in speech development: perceptual targets and sensori-motor maps for synthesized French vowels from birth to adulthood[END_REF]. For a given growth stage, the MVS is defined as the maximal acoustic space, in the F1-F2-F3 dimension, obtained by a uniform distribution of the entire input space of command parameters. All possible vowels of the world's languages can be situated within that space. The stimuli were based on the 38 monophthong oral vowel prototypes in the UCLA Phonological Segments Inventory Database (UPSID), developed by Maddieson [START_REF] Maddieson | Patterns of Sounds[END_REF] and described in Vallée [START_REF] Vallée | Systèmes vocaliques: de la typologie aux prédictions[END_REF]. The UPSID prototypes were an appropriate sample covering the entire MVS, while ensuring articulatory coherence and a reasonable number of stimuli. First, the four corner vowels /i y u a/ were situated at the limits of the MVS, according to the Dispersion-Focalization Theory (DFT) criteria [START_REF] Schwartz | The dispersion-focalization theory of vowel systems[END_REF]. The DFT assumes that vowel systems are shaped by both dispersion constraints that increase mean formant distances between vowels, and focalization constraints that increase the trend to have focal vowels in the system, that is, vowels with close adjacent formants (F3 and F4 for /i/, F2 and F3 for /y/, F1 and F2 at their lowest mean position for /u/, and F1 and F2 at their highest mean position for /a/). The remaining 34 acoustic prototypes were distributed according to their mean F1, F2, and F3 values provided by previous studies of these vowels in various languages (for a review, see [START_REF] Vallée | Systèmes vocaliques: de la typologie aux prédictions[END_REF]). Once established, the optimal acoustic F1, F2, and F3 values were related to their underlying articulatory values (command parameters in VLAM) by an inversion procedure exploiting the pseudo-inverse of the Jacobian matrix (see [START_REF] Ménard | Role of vocal tract morphology in speech development: perceptual targets and sensori-motor maps for synthesized French vowels from birth to adulthood[END_REF] for more details). The values of the fourth and fifth formants and the bandwidth values were calculated with the algorithm found in Badin and Fant [START_REF] Badin | Notes on vocal tract computation[END_REF]. The poles of the transfer function were excited through a 5-formant cascade synthesis system [START_REF] Feng | Vers une synthèse par la méthode des pôles et des zéros[END_REF], by a pulse train generated by a source according to the Liljencrants-Fant (LF) model [START_REF] Fant | A four-parameter model of glottal flow[END_REF]. The parameters related to the source (glottal symmetry quotient and open quotient) were equal to 0.8 and 0.7, respectively, and remained unchanged for all growth stages. The resulting signal was sampled at 22,050 Hz and was 500 ms long. Fundamental frequency values were chosen based on the growth data presented by Beck [START_REF] Beck | Organic variation of the vocal apparatus[END_REF]. A rising-falling F0 contour was extracted from a natural vowel production and used to shape the stimuli's F0 contours.

Those stimuli were used in previous auditory categorization experiments conducted with adult subjects [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF][START_REF] Ménard | Role of vocal tract morphology in speech development: perceptual targets and sensori-motor maps for synthesized French vowels from birth to adulthood[END_REF]. This adult dataset, shown in Table I, was presented to each participant.

[Insert Table I]

Non-adult stimuli

Three other sets of synthesized stimuli were generated for three growth stages: newborn, 4 years old, and 8 years old (corresponding to vocal tract lengths in VLAM of 7.74 cm, 10.85 cm, and 12.11 cm, respectively and Fo values of 450 Hz, 337 Hz, and 260 Hz, respectively). To achieve this, MVS were generated for each age; the 38 prototypical acoustic locations of the UPSID database were superimposed on each MVS; and the corresponding F1, F2, and F3 values were used to synthesize the 38 sound files. As was the case for the adult stimuli dataset described earlier, the underlying articulatory command parameters were retrieved using an inversion procedure. As we demonstrated in previous papers [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF][START_REF] Ménard | Auditory normalization of French vowels synthesized by an articulatory model simulating growth from birth to adulthood[END_REF][START_REF] Ménard | Role of vocal tract morphology in speech development: perceptual targets and sensori-motor maps for synthesized French vowels from birth to adulthood[END_REF], a given location within a child's MVS does not necessarily involve the same articulatory settings for the comparable location within the adult's MVS. To ensure a more exhaustive dataset, acoustic results of the articulatory commands determined for the adult stimuli dataset were also generated, yielding an additional set of 38 sound files, for a total of 76 synthesized stimuli in each of the three younger vocal tracts (newborn, 4 years old, and 8 years old). Those stimuli are depicted, in the F1 versus F2 space, in Figure 1. The formant and bandwidth values of the newborn vocal tract are summarized in Table II.

Distribution of stimuli between listeners

The two 4-year-old subjects were asked to identify stimuli corresponding to a 4year-old child (76 stimuli, upper-left panel in Figure 1) and an adult (38 stimuli, lowerright panel in Figure 1). The four 8-year-old subjects were asked to identify stimuli corresponding an 8-year-old child (76 stimuli, upper-right panel in Figure 1) and to an adult (38 stimuli, lower-right panel in Figure 1). The six adult subjects were asked to identify stimuli corresponding to an adult (38 stimuli, lower right panel in Figure 1) and to a newborn (76 stimuli, lower-left panel in Figure 1). That is, all participant groups perceived two different sets of stimuli-one close to their age (4 years old, 8 years old, or adult) and one very different from their age (adult for children, newborn for adults). The grouping of children into 4-year-old and 8-year-old age categories enabled us to limit the number of required stimuli. The fact that the age grouping was not very accurate had limited consequences, since the difference between the subject's age and the VLAM age was less than 2 years for each child, which corresponds to a less than 6% difference in vocal tract size.

All stimuli for the newborn, 4-year-old, 8-year-old, and adult (21-year-old) , versions of VLAM are depicted in the F1 versus F2 space in Figure 1.

Experimental procedure

Participants had completed the production task (described in [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF]) before the perception task. In the current study, each participant was presented with a set of random stimuli. The stimuli were presented binaurally via high-quality headphones. The participant was instructed to identify, by selecting an icon on a screen, the perceived vowel among the ten French oral vowels /i y u e ø o ɛ oe ɔ a/. Those vowels represent phonological contrasts along four height degrees: high (/i y u/), mid-high (/e ø o/), midlow (/ɛ oe ɔ/), and low (/a/). French also features contrasts along the place of articulation ). The test lasted about 10 minutes and took place in a soundproof room. The stimulus presentation was blocked according to the adult and non-adult dataset. The task was self-paced. The inter-stimulus interval was 1 second. For the 4-year-old participants, words were replaced by images of the words or puppets. During a familiarization phase, the experimenter ensured that the child could associate the correct word with the image. During the test, the child pointed to the answer with his or her finger, and the experimenter selected the corresponding image with the computer mouse. The limitation of test duration to 10 minutes -which imposed a limited dataset with only one identification answer per stimulus point -was necessary for this group of very young subjects.

Data analysis

Perceptual center of gravity

Values of the stimuli's first two formants (F1 and F2) were first converted to the Bark scale, since this scale models the perceptual distribution of frequencies in the human auditory system based on the formula found in Schroeder et al. [START_REF] Schroeder | Objective measure of certain speech signal degradations based on masking properties of human auditory perception[END_REF]: F Bark = 7*asinh(F Hz / 650). Each stimulus was associated with its perceived label. This resulted in associating to each vowel category a series of stimuli perceived as members of this category. Then, the mean F1 and F2 values of the perceived vowel category (corresponding to the center of the category) were calculated.

This method of summarizing a complete coherent identification area by using just its center of gravity has been used in various speech perception experiments since those of Ainsworth [START_REF] Ainsworth | Intrinsic and extrinsic factors in vowel judgments[END_REF] (see e.g. [START_REF] Nearey | Static, dynamic and relational factors in vowel perception[END_REF]). Ainsworth discussed the possible drawback of using this summary, in terms of possible boundary effects (that he called "windowing") and unequal density of the stimuli inside the acoustic space. However, these effects are unlikely to be problematic here considering that (1) comparisons between the front and back areas of the vowel space are based on rather even distributions in these areas, as displayed in Figure 1; (2) comparisons between various ages are based on rather similar distributions from one age to the other, at least for infant/children sets; and [START_REF] Rizzolatti | The mirror-neuron system[END_REF] comparisons between distributions from one subject to another in the adult space are based on a single dataset, which is the same for all subjects. Moreover, possible effects related to density or windowing should only result in producing noise or bias, which would possibly decrease the significance of tested correlations, but not increase them.

Finally, the perceptual data was successfully tested and presented no significant departure from a Gaussian distribution (see Note 1).

Relative position along F1

In order to quantify the distribution of high, mid-high, mid-low, and low vowels along F1, according to the method used by Ménard et al. [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF] and Neagu [START_REF] Neagu | Analyse articulatoire du signal de parole: caractérisation des syllabes occlusive-voyelle en français[END_REF], we compared the distance in the F1 dimension, in Bark, between vowel categories of different heights. High, mid-high, mid-low, and low vowels were respectively associated with 1, 2, 3, and 4 degrees. Then the following calculations were carried out, based on the data in Bark:

• For each participant, mean F1 values for each vowel category were computed (x j , where j is one of the ten French oral vowels /i y u e ø o ɛ oe ɔ a/).

• We defined m 1 = (x i +x y +x u )/3 and m 4 = x a as the minimal and maximal F1 values for the participant in question.

• A normalized index for each of the mid-high and mid-low vowels was computed by the formula: y j = 100*(x j -m 1 )/(m 4 -m 1 ), j∈ /e ø o ɛ oe ɔ/.

A schematic representation of the method, reproduced from Ménard et al. [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF], is shown in Figure 2. This method proved to be suitable in the examination of vowel target alignment in the production dataset [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF].

[Insert Figure 2]

Statistical analyses

Statistical analyses were conducted to determine if these normalized indexes for mid-high and mid-low vowels were similar across place/roundedness values (stable within-listener F1-series) and variable across listeners (variable between-listener F1series). For this aim, an ANOVA was carried out on these normalized indices (dependent variable) with height (mid-high or mid-low) and place/roundedness (front unrounded, front rounded, or back) as the within-subject fixed factors, and subject as the random factor. Interaction effects were further explored by planned comparisons using the Bonferroni correction with the alpha level set to 0.05.

Then, correlation analyses were carried out between normalized F1 values for produced versus perceived vowels, for each of the mid-high and mid-low categories, for all subjects. The production data had been acquired previously, and they were reported in a previous study of the CO corpus [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF]. The resulting data (Figure 4 in [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF]) are displayed in Figure 3. The perception data were provided by extrinsically-normalized indices for stimuli at the corresponding age groups in VLAM (4 years old, 8 years old, or adult) depending on the subject's age (see Section 2.4.2).

[Insert Figure 3]

Results

Perceived height along the F1 dimension

The relative positions of the perceived French vowels along the F1 dimension (indices computed as described earlier in Figure 2) for each listener are presented in Figure 4, for the stimuli generated in the adult vocal tract. In this graph, the relative positions of mid-high and mid-low vowels along the F1 dimension are represented as a percentage of the speaker's F1 range (distance between high and low vowels). Low yvalues (in the upper portion of the graph) corresponding to mid-high vowels reflect the small F1 distances between high and mid-high vowels, whereas high y-values for midlow vowels stand for the large F1 distances between high and mid-low vowels. For each speaker, the values for the three mid-high vowels are linked by a solid line, whereas the values for the three mid-low vowels are linked by a dotted line. Long solid or dotted lines denote large within-speaker variation in the F1 values within a given height degree.

Speakers are sorted along the x-axis in ascending order of their y-data points for mid-high vowels.

[Insert Figure 4] Figure 4 shows great between-speaker variability in the relative position of midhigh vowels, as depicted by the position of the solid lines along the y-axis. Indeed, values range from 10 (minimal value) to 58 (maximal value), resulting in a between-speaker variability of 48. The same pattern of between-speaker variability was observed for midlow vowels. Y-values for these data points ranged from a minimal value of 47 to a maximal value of 78 (for a between-speaker variability of 31). At first glance, we notice that no effect of age is found, as revealed by the fact that speakers from all three age groups had both small and large y-values. Despite this variability, for most participants (A 5 , A 2 , 4 1 , 8 2 , 8 1 , A 6 , 4 2 ), vowels belonging to the same height degree tended to be perceived with similar F1 values. This pattern is noticeable, on Figure 4, by the fact that the three mid-high vowels /e ø o/ have y-values close to each other and/or the three midlow vowels /  / have y-values close to each other. The within speaker differences in y-values between each of the two vowel classes is less than the between-speaker variability for the corresponding height degree. This pattern is less clear for the other speakers (A 3 , 8 3 , 8 4 , A 1 , A 4 ). Nonetheless, a mixed ANOVA conducted on the y-values with height and place/roundedness as within-subject fixed factors and subject as a random factor revealed a significant effect of height, F(1,11) = 86.003, p < .05, with midhigh vowels having higher values than mid-low vowels, as expected. The subject factor did not have a significant main effect on the variation of indices. No effect of place/roundedness was found, as a main effect or in interaction with height or subject.

However, the interaction between height and subject was significant, F(11,19) = 4.061, p < .05, with some speakers having smaller perceived F1 values for a given height degree than others.

[Insert Figure 5] The relative positions of the perceived vowel categories along F1 for the stimuli generated in the newborn, 4-year-old, and 8-year-old vocal tracts are presented in Figure 5. Similar indices as in Figure 4 are presented in Figure 5. As was the case for the data perceived within the adult vocal tract (Figure 4), the perceived data generated in younger vocal tracts show great between-speaker variability. Indeed, for mid-high vowels /e ø o/ (solid line), values range from 7 (minimal value) to 48 (maximal value), resulting in a between-speaker variability of 41. The same pattern of between-speaker variability was observed for the mid-low vowels /ɛ oe ɔ/ (dashed line). Y-values for these data points ranged from a minimal value of 40 to a maximal value of 81 (for a between-speaker variability of 41). For most participants (A 3 , A 2 , A 4 , 8 2 , A 5 , 4 1 , A 6 ), within-speaker variability for a given height degree (as measured by the height of the solid or the dashed line) was smaller than the range of between-subject variability. This pattern was less clear for the other participants. As was the case for the analysis presented above, a mixed ANOVA conducted on the y-values with height and place/roundedness as within-subject fixed factors and subject as a random factor revealed a significant effect of height, F(1,11) = 73.609, p < .05, with mid-high vowels having higher values than mid-low vowels, as expected. No effect of place/roundedness was found, as a main effect or in interaction with height or subject. Only the interaction between height and subject was significant, F(11,22) = 3.346, p <.05.

Correlations between perceived F1 values in the adult vocal tract and the younger vocal tracts

The latter finding confirms that the distances between height degrees y are variable across speakers but that most speakers tend to align all perceived vowels of a given height along the same F1 values. This is true for various "ages" and accordingly various sizes of the vocal tract used for generating the stimuli, as revealed by Figures 4 and5. This result may be related to the fact that the alignment pattern does not operate along the raw F1 dimension, but rather at a higher acoustic-auditory level. To explore this hypothesis, relative perceived F1 values (y-values in Figures 4 and5) in the adult dataset were plotted against relative perceived F1 values in the younger vocal tracts dataset, in Figure 6. In this graph, each speaker is represented by 6 data points (3 relative perceived F1 values for the three mid-high vowels and 3 relative perceived F1 values for the three mid-low vowels). As can be observed in this graph, the relative partition of the F1 dimension for each mid-high and mid-low vowels at the perceptual level for different vocal tract sizes are highly correlated. A linear regression analysis was performed on the data and revealed an r 2 value of 0.77 (p < .001), with a regression line close to the first diagonal. Separate linear regression analyses for the mid-high and the mid-low series also showed a high degree of correlation (for mid-high vowels: r 2 =.52; for mid-low vowels: r 2 = 021) that was significant (p <.01) for both correlations. Finally, individual regressions between normalized F1 values for the two sets of stimuli for each listener are displayed in Table III (a), and are significant for the 6 mid-high and mid-low vowels. subject variability at the perceptual level can be largely accounted for by the produced values.

In a second step, perceived vowels were considered at the other VLAM age for each subject (that is adult for children and newborn for adults). Not surprisingly, considering the high correlation between normalized F1 values for the two sets of stimuli for each listener (Table III[a]), correlations were once again significant for the six vowels, with r 2 values ranging from 0.34 to 0.62. Since such correlations between perceived and produced vowel targets are obtained both for auditory stimuli synthesized on a version of VLAM with the same "age" and with a very different age, the "inaccurate" character of age grouping in the three gross categories, discussed in Section 2.2.3, appears retrospectively as not at all problematic.

[Insert Figure 7]

Discussion

The results suggest that perceived vowel height in the French language is organized in a way that reveals idiosyncratic patterns. For most participants, vowel targets belonging to similar height degrees, independent of place of articulation or roundedness, are aligned along similar subject-specific F1 values. This pattern echoes the one we found at the production level for the same cohort of speakers [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF], which indicates a link between speech perception and speech production, in relation with the debate about auditory versus motor theories of speech perception.

The perceptual vowel space shaped by production constraints

The existence of a perceptuo-motor link seems clearly displayed in the present data, which raises the question: Does idiosyncrasy in these data come from a productionbias projected onto perception, or from a perception-bias projected onto production?

No clear perceptual basis for the perceptuo-motor vowel height idiosyncrasy

A perceptual origin of the bias seems rather unlikely. First, the F1 values for a given subject generally do not conform to a criterion of maximal acoustic distance.

Indeed, these values seldom correspond to 33 and 67, which would mean that vowels of different height degrees were equally spaced along the F1 dimension. Perceptual contrast is nonetheless sufficient [START_REF] Lindblom | Phonetic universals in vowel systems[END_REF].

It could be advocated that the specific F1 values corresponding to each vowel height degree might be related to the production-perception link as demonstrated by Perkell and colleagues ( [START_REF] Perkell | The distinctness of speakers' productions of vowel contrasts is related to their discrimination of contrasts[END_REF], [START_REF] Perkell | The distinctness of speakers' /s/-/ʃ/ contrast is related to their auditory discrimination and use of an articulatory saturation effect[END_REF]). Indeed, the produced distance between height degrees, in terms of percentage of the speaker's F1 range from high to low vowels, may be driven by the perceived distance between the auditory targets related to height degrees.

Hence, for a given subject, two series of produced vowels, along the F1 dimension, may be close to each other because the auditory discrimination acuity of this subject between both F1 sets of F1 values is poor. On the other hand, greater distances in F1 between both series of produced vowels for another subject might originate from good auditory discrimination acuity. However, it is unlikely that this perceptual bias also drives the alignment of the three vowels belonging to the same height degree on similar F1 values. Furthermore, there is no strong reason to expect such large differences between one subject and another in auditory acuity differences along F1, apart from general hearing trouble or special auditory competence, which should not result in strong variations within the F1 space but rather a global superiority in acuity from one subject to another.

A possible motor basis, the "Maximal Use of Available Contrasts" principle

In our previous study about idiosyncrasies in speech production, we introduced a possible motor explanation, which could explain inter-speaker variability, and result in inter-listener variability if perceptual and motor repertories are coupled in some way. This explanation was based on what we called a "Maximal Use of Available Contrasts" (MUAC) principle, extending the concept of "Maximal Use of Available Features" (MUAF) introduced by Ohala [START_REF] Ohala | Moderator's introduction to symposium on phonetic universals in phonological systems and their explanation[END_REF]. In the course of speech acquisition, once an articulatory control is acquired (such as variation in height degrees for front vowels), it would be easier to integrate new controls (such as variation in place of articulation and roundedness) into already existing ones, namely, to use similar F1 values for various vowels of similar height. Since tongue height can be related to stable F1 values across place of articulation and roundedness [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF], the tongue-palate distance would provide a good proximal somatosensory invariant parameter related to vowel height degrees. Thus, producing a mid-high vowel, for instance, involves producing the tongue-palate distance associated with this specific height degree, independent of place of articulation and roundedness.

The present results suggest that the MUAC principle could also shape the speakerspecific organization of the vowel space in perception. Preferred values of F1 or tonguepalate distances for a given vowel height degree, reflecting the MUAC principle, would act as anchors in the organization of the vowel space for both perception and production, and lead to idiosyncrasy related to child-specific developmental pathways [START_REF] Vihman | Phonological development from babbling to speech: common tendencies and individual differences[END_REF], and the developmental pathways are possibly established in relation to the ability to produce a sufficient -though not optimal -perceptual contrast in the vowel system of the selected language. This agrees with a number of exemplar models of speech perception (e.g. [START_REF] Johnson | Speech perception without speaker normalization: an exemplar model[END_REF][START_REF] Goldinger | Echo of echoes? An episodic theory of lexical access[END_REF]) in which one's own speech experience provided by the speech production system would feed the speech perception system with exemplar items incorporating a natural link between auditory and articulatory dimensions in a principled way.

In summary, speech perception would be shaped by an idiosyncrasy in speech production, originating from a developmental motor learning scenario leading to MUAC and stabilizing to a certain extent some inter-individual differences in motor control for vowel height. Of course, this kind of perceptual idiosyncrasy, possibly mirroring motor idiosyncrasy, would not impede a listener to process sounds produced by any speaker of the processed language, by applying all means provided by statistical or dynamic processing of continuous speech. The specific setting of prototypes in the phonemic repertoire stays compatible with the categories of the native language, and hence it enables the individual to process speech by any speaker of the native language. It can be envisioned, however, that speech from some speakers is easier to process than that from others, and that this variability is listener dependent: some "accents" are closer to the listener's own accent, which likely makes that speaker's speech easier to process than that of other speakers who have a greater number of different idiosyncrasies.

To evaluate this, we are conducting further experiments. In one experiment we are studying the idiosyncrasies inside a given family, to examine whether different idiosyncrasies might exist for brothers and sisters, despite their common phonetic environment during speech acquisition. In another experiment we are assessing the joint of the vowel repertoire in production and in perception in post-lingual deaf subjects after cochlear implantation, to determine if implantation results in slight modification of the implementation of vowel height control, and whether perceptual maps evolve in coordination with motor maps.

Interpretation in the framework of the Perception for Action Control Theory

The present finding adds some evidence to a number of previous studies suggesting that knowledge about speech production could play a part in speech perception (see a discussion in [START_REF] Schwartz | Filling the perceptuo-motor gap[END_REF]). While this could be conceived as an argument in favor of "pure" gestural theories (e.g. [START_REF] Liberman | The motor theory of speech production revised[END_REF][START_REF] Fowler | An event approach to the study of speech perception from a directrealistic perspective[END_REF]), other arguments about the role of perceptual processing in the definition of speech production targets and motor behaviors lead us to claim that the communication units are neither purely perceptual, nor purely motor, but intrinsically perceptuo-motor in nature [START_REF] Schwartz | Phonology in a theory of perception for action control[END_REF][START_REF] Boë | Linking the Dispersion-Focalization Theory (DFT) and the Maximum Utilization of the Available Distinctive Features (MUAF) principle in a Perception for Action Control Theory (PACT)[END_REF].

In the Perception for Action Control Theory (PACT) that we have been developing over the past few years [START_REF] Schwartz | Phonology in a theory of perception for action control[END_REF][START_REF] Boë | Linking the Dispersion-Focalization Theory (DFT) and the Maximum Utilization of the Available Distinctive Features (MUAF) principle in a Perception for Action Control Theory (PACT)[END_REF][START_REF] Schwartz | The Perception for Action Control Theory (PACT): a perceptuo-motor theory of speech perception[END_REF]), we endorse a view in which (1), perceptual representations are indeed auditory (or audiovisual) in nature, and not motor, which takes into account the nonlinearities in the articulatory-to-auditory transform [START_REF] Stevens | On the quantal nature of speech[END_REF] shaping speech objects in a perceptually efficient way (e.g. [START_REF] Schwartz | A strong evidence for the existence of a large scale integrated spectral representation in vowel perception[END_REF]); and (2), perceptual and motor repertoires are, however, jointly shaped in development, inducing implicit articulatory knowledge inside perceptual representations. In PACT, the communication unit through which parity may be achieved is neither a sound nor a gesture but a perceptually-shaped gesture, that is, a perceptuo-motor unit. In this framework, the possibility that online access to motor resources could enhance perceptual representations remains to be determined (see [START_REF] Schwartz | The common language of speech perception and action: a neurocognitive perspective[END_REF]).

PACT includes the hypothesis of a co-structuring of perceptual and motor representations in the course of speech development, enabling auditory categorization mechanisms to take motor information into account. While it seems clear that auditory categorization processes exist and develop earlier than speech production knowledge in ontogeny [START_REF] Eimas | Speech perception in infants[END_REF][START_REF] Jusczyk | The role of attention in speech perception by young infants[END_REF], the further development of motor procedural knowledge would, in PACT, modify and possibly enhance the perceptual repertoire. It is also at this level that subtle online transient modifications of motor or auditory repertories could take place in various kinds of adaptation paradigms or motor resonance phenomena.

The present work is relevant in this framework. It shows rather strikingly that the motor repertoire is specified differently from one subject to another, and that these differences in motor implementation are accompanied by differences in the perceptual repertoire. The interpretation in the PACT framework is that a developmentally learnt motor repertoire provides a bias to an auditory categorization module.

The fact that there is a correspondence between normalized F1 values in the two vocal tract sizes for each listener (see Figure 6) suggests that there exists an auditory normalization module at some stage in the perceptual architecture. A classical normalization parameter, according to authors such as Disner [START_REF] Disner | Evaluation of vowel normalization procedures[END_REF] or Traunmüller [START_REF] Traunmüller | Perceptual dimension of openness in vowels[END_REF] is provided by the distance F1-F0 in Bark. In a previous work on normalization parameters for vowel perception [START_REF] Ménard | Auditory normalization of French vowels synthesized by an articulatory model simulating growth from birth to adulthood[END_REF], we proposed a triplet-(F1-F0) for height, (F2-F1) for frontedness, and F'2 for rounding (all values in Barks)-and showed that these parameters provide efficient normalization parameters for describing synthesized French vowels. In Table III (c) we show that values of F1-F0 in Bark between the two sets of stimuli are highly correlated within listeners for the 6 tested vowels.

Of course, other kinds of perceptuo-motor links may exist; for example, motor schemas may play a role at a lower level, in the auditory characterization per se, before categorization, but this is beyond the scope of the present paper. In any case, the role of some motor knowledge on perceptual processes seems highly likely in view of the present data.

Conclusion

In this study, we have shown that the vowel space perceived by French listeners displays stable F1 values for a given vowel height degree (mid high or mid low), although there are large inter-individual differences. This pattern appears stable for stimuli generated in child or adult vocal tract models. The variations in the distribution of F1 values from one subject to another appear to be correlated from perception to production. This adds a new element to the increasing data that suggest there is a link between speech perception and speech production, which is compatible with the Perception for Action Control Theory (PACT) view that speech communication is mediated by perceptuo-motor units that are gestures shaped by auditory (and more generally multisensory) processes.

NOTE

1. Gaussian tests were performed on the distance to regression curves, grouping all vowel categories, with no significant departure from the normality assumption, suggesting a regular distribution of perceptual and motor data: chi 2 (5) = 6.10, p = .30. high vowels and /a/) for the 12 participants in the production task (from Menard et al [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF], Figure 4). Data are presented separately for mid-high (/e ø o/, solid line) and midlow vowels (/ɛ oe ɔ/, dotted line). y j is calculated as (x j -m 1 )/(m 4 -m 1 )*100, where m 1 = (x i +x y +x u )/3, m 4 = x a and j is one of the six perceived French oral vowels /e ø o ɛ oe ɔ/, for each speaker. For a given height degree and a given speaker, the y-values of the three vowels are linked by a vertical bar. Speakers are sorted along the x-axis in ascending order of their y-data points for mid-high vowels.

FIGURE CAPTIONS:

Figure 4: Mean values of relative position along F1 (as a % of the F1 difference between high vowels and /a/) for the 12 listeners, for the 38 perceived stimuli generated in the adult vocal tract. Data are presented separately for mid-high (/e ø o/, solid line) and midlow vowels (/ɛ oe ɔ/, dotted line). y j is calculated as (x j -m 1 )/(m 4 -m 1 )*100, where m 1 = (x i +x y +x u )/3, m 4 = x a and j is one of the six perceived French oral vowels /e ø o ɛ oe ɔ/, for each speaker. For a given height degree and a given speaker, the y-values of the three vowels are linked by a vertical bar. Speakers are sorted along the x-axis in ascending order of their y-data points for mid-high vowels.

Figure 5: Mean values of relative position along F1 (as a % of the F1 difference between high vowels and /a/) for the 12 listeners, for the 76 perceived stimuli generated in the 4year-old, 8-year-old and newborn tracts. Data are presented separately for mid-high (/e ø o/, solid line) and mid-low vowels (/ɛ oe ɔ/, dotted line). y j is calculated as (x j -m 1 )/(m 4m 1 )*100, where m 1 = (x i +x y +x u )/3, m 4 = x a and j is one of the six perceived French oral vowels /e ø o ɛ oe ɔ/, for each speaker. For a given height degree and a given speaker, the y-values of the three vowels are linked by a vertical bar. Speakers are sorted along the xaxis in ascending order of their y-data points for mid-high vowels.

  (e.g., front [/i y e ø ɛ oe/] or back [/u o ɔ/]) and roundedness (e.g., front unrounded [/i e ɛ/] or front rounded [/y ø oe/]). Each vowel was represented by a monosyllabic word of the structure [fV(C)] : « fil » ([fil]), « fée » ([fe]), « fer » ([fɛʁ]), « fa » ([fa]), « fut » ([fy]), « feu » ([fø]), « fleur » ([floeʁ]), « fou » ([fu]), « faux » ([fo]), « fort » ([fɔʁ]

Figure 1 :

 1 Figure 1: Stimuli used for the perceptual task, in the F1 and F2 space, in Hertz. The 4-

Figure 2 :

 2 Figure 2: Schematic representation of the metric used to evaluate between-speaker and

Figure 3 :

 3 Figure 3: Mean values of relative position along F1 (as a % of the F1 difference between

Figure 6 :

 6 Figure 6: Linear regression analysis of the relative positions along F1 of the perceived

Acknowledgments

This work was supported by the Social Sciences and Humanities Research Council of Canada and the Natural Sciences and Engineering Research Council of Canada. Thanks to Marlene Busko for copy-editing the paper.

[Insert Figure 6] [Insert Table III] Hence, for each listener, a specific categorization rule would be applied, based on the listener's internal F1-series templates. Next, we sought to determine how these templates relate to those evidenced in the participants' own vowel production.

Correlations between produced and perceived F1 values

The results for the current experiment were very similar to our previous findings at the production level [START_REF] Ménard | Invariance and variability in the production of the height feature in French vowels[END_REF], for the same subjects. In order to investigate the relationship between produced and perceived vowel height degrees, a linear regression analysis was carried out on the relative position along the F1 values (extrinsically-normalized index) of the produced versus perceived vowels for each of the mid-high and mid-low categories. In a first step, perceived vowels were considered at the same theoretical age in VLAM as the subject's age, in order to match as much as possible the vocal tract characteristics in production and perception. The correlation plots are presented in Figure 7 for the three mid-high vowels for illustration, and all correlation results are provided in Table III (b). They are significant for the six vowels, with rather high r 2 values. The plots in Figure 7 show that the normalized F1 indices are rather close in terms of production and perception for each speaker, as shown by the fact that the values would be adequately fitted by the first diagonal in each diagram (dotted line). Thus, the considerable between-the three mid-low vowels. The correlation is significant and the correlation coefficient (R 2 ) is 0.77 (p < 0.001).


Angela Barthes

Yves Alpe

Barbara Bader

Keywords: French contexts, Education for Sustainable Development, school form, university pedagogy, legitimacy

Introduction:

In France, the "school form" established in the late nineteenth century [START_REF] Vincent | L'éducation prisonnière de la forme scolaire[END_REF][START_REF] Monjo R | La forme scolaire dans l'épistémologie des sciences de l'éducation[END_REF] led to, admittedly, as necessities inherent in the act of teaching, a certain number of features: impersonal rules and hierarchical structure in the classroom, one teacher in charge of a group of students sorted by age, the existence of a distinct and closed location. But the school form also applies to educational content, by imposing a horizontal division of knowledge into "school subjects", based on scientific knowledge for reference. It assumes a cumulative nature of knowledge, and a control of the transmission process and its results (examinations, diplomas, inspections). These characteristics of the school form were also described and discussed in schools and universities in the United States and Canada. Henry Giroux and the authors of critical pedagogy offer a thorough analysis of this subject (Giroux, 1988(Giroux, , 2006)).

In France, its organization builds, from the time of J. Ferry, on the definition of specific issues that go far beyond the framework of the school: eradication of local particularities, the spreading of values of modernity, the exaltation of national pride and citizenship. It is recognized that education as a whole contributes to it, as it contributes to the symbolic figurehead of the schoolmaster. The education system is thus designed both to teach and educate. These sociopolitical functions of the school [START_REF] Prost | Éducation, société et politiques. Une histoire de l'enseignement en France de 1945 à nos jours. [education, society and politic: theaching history in France from 1945[END_REF], analyzed since the beginning of the twentieth century by E. Durkheim (1992) thus justify the presence in the teachings of values (ethics, citizenship, patriotism ...) or even ideological positions that were rarely questioned until the sixties.

This positioning of values experienced a progressive narrowing in the slow process of the didactization of school content . The massification of education (Merle, 2009) gives priority to the content of knowledge. Mistrust resulting from the questioning of ideologies [START_REF] Baudelot | L'école capitaliste en France[END_REF] of the functions of the school (inequality of educational opportunities, the role of cultural capital ...) through the development of the sociology of education and the "theory of reproduction " [START_REF] Bourdieu | Le partenariat, entre réticences et fascination : quels questionnements éthiques pour l'institution scolaire ? [The partnership between reluctance and fascination: what ethical questions for the school[END_REF] led to the suspicion of anything that seemed to be more or less of a" hidden curriculum " [START_REF] Perrenoud | Curriculum : le formel, le réel, le cache[END_REF]. Thus, many professors consider themselves strictly as teachers; they are no longer educators. They base their social legitimacy on the scientific and academic legitimacy of the knowledge they provide. Education in school will therefore organize itself around the question of the fundamental knowledge to teach. It consists of determining a minimal educational base required, which is divided by categories of age.

In parallel, a utilitarian concept of education is drawn based on future employability, which is accompanied by the rise of the competency model inspired by the enterprise [START_REF] Rope | Savoirs et compétences[END_REF]. It claims to meet a crisis in education (Joshua, 1999), characterized by the doubt about the social utility of knowledge. Thus, in Quebec, there is a reaffirmation of the importance of teaching the fundamental knowledge in school before the implementation of referentials for progression of learning in primary schools and secondary schools, in addition to focusing on skills development in schools («See for example : Ministry of Education, Recreation and Sports, Government of Quebec, 2008).

The rise, at least in the perceptions of social problems such as environmental degradation, incivility and violence, will bring a new change with the emergence in the 90's in France of Environmental Education (Girault & Sauvé, 2008), followed by Civic, Legal and Social Education [START_REF] Alpe | Questions socialement vives, enjeux sociaux et didactiques : la création d'un enseignement d'éducation civique juridique et sociale en France[END_REF], Health Education (Eymard, 2004) and Education for Sustainable Development (ESD). These "educations for" [START_REF] Audigier | Compétences et contenus. Les curriculums en questions[END_REF] call into question the sharing between the function of instruction, centered on knowledge, and the function of education, centered on the values to be transmitted. These same issues arise in the North American context, Canadian and Quebecker, as to the nature of values to be transmitted or preferred style of teaching, especially when it comes to education related to the environment and sustainable development [START_REF] Bader | Education[END_REF][START_REF] Bader | Rapprochement interdisciplinaire entre une éducation aux sciences citoyenne et l'éducation relative à l'environnement : points de vue de chercheurs et formation des enseignants[END_REF]Sauvé and Orellana, 2008;Sauvé 2007). This article is placed in this context and its purpose is to show, from the example of ESD at the university, how in France, there is a rupture in the educational logics, which raises questions about the legitimacy of content transmitted. Our work is also situated in a broader international perspective, in line with those who question ESD in university programs, whether in Europe [START_REF] Scott W | Higher education and ESD in England: a critical commentary on recent initiative[END_REF]Scott, 2008, Ségalas, Ferrer-Balas, Svanstrom, Lundvist &[START_REF] Segalas | What has to be learnt for sustainability? A comparison of bachelor engineering education competences at three European universities[END_REF], in a North American context or elsewhere (Ferrer-Balas, Adachi, Banas, Davidson, Hoshikoshi, Mishra, Motodoa, Onga & Ostwald, 2008).

Content and practices of ESD at the university in France

From supranational political order to the French adaptation In education systems today, the organization of ESD is a response to the UN program of sustainable development (Sauvé, 2006). UNESCO, acting as an implementing agency of the United Nations, has set up a "decade of ESD" (2004ESD" ( -2014)), whose objective is to stimulate reforms of education systems and curricula to promote sustainable development. Relayed by the European bodies, and then states, the demands on universities have gradually increased. Higher education institutions must lead the way, through ESD, towards the implementation of sustainable development. Thus, as critically observed by Lucie Sauvé, "Sustainable development is the subject of an educational project prescribed by the authorities of both international and national governance, and the education community must engage" (Sauvé, Berryman & Brunelle, 2003).

This stance therefore calls ESD in a resolutely political direction (Jicking and Wals, 2008), starting from international bodies and spreading in universities. Laval and Weber (2002) even speak of a "new order global education."

In this sense, the Talloires Declaration1 is the first official mark of commitment from universities towards promoting education for sustainable development. Signed by 350 universities, it is intended, among other things, to "develop a mindset in institutions focused on sustainable development", and focus on "education leading to an environmentally responsible citizenship". Implementations are reinforced by international conferences, which give more importance to the commitment of universities to education for sustainable development.

In France, the Grenelle of the environment specifies the modalities for the dissemination of education for sustainable development by requiring all higher education institutions to prepare, for the start of 2009, a "Green Plan" for the campus. This same type of project can be found in the English universities (Beringer, Adomßent and Scott, 2008). The objectives are numerous: integrating sustainable development in training, making ESD fully interdisciplinary, providing teachers with pedagogical tools and specific training, integrating sustainable development in study missions, advice or support from businesses or communities that can lead the institution or its students; integrating sustainable development into courses and / or business projects, supporting and enhancing student engagement in the achievement of sustainable development projects.

In this context, university education experiences rapid evolution, and ESD is supposed to be gradually more pertinent. These developments need to be clearly formulated and analyzed with respect to their objective and consequences. Indeed, the hypothesis is made here, that in the absence of a formal curriculum, courses tend to be organized around values and practices to the detriment of the disciplinary scientific content.

Content oriented by the practices of actors and the partnership

Indeed, as everywhere, ESD as environmental education puts forward a principle of partnership or collaboration with local associations and the associated sphere [START_REF] Villemagne | L'éducation relative à l'environnement des adultes en contexte communautaire: vers un modèle théorique [Environmental Community Adult Education: An Emerging Theoretical Model[END_REF][START_REF] Corcoran | Young people, education and sustainable development[END_REF]. This partnership stipulates the idea of educational co-construction in the sense of collaboration between the different actors involved in the process of developing guidelines and training content. This position raises a number of criticisms as much as from a point of view on ethical issues related to the educational institution (Brussels, 2006), as from the point of view of the legitimacy of the teachings. The authors even formulate the idea of a utilitarian and dominant partnership [START_REF] Barthes | Éducation au développement durable et territoires ruraux. Problématique, projet de territoire et réduction fonctionnelle de l'enseignement[END_REF].

In fact, the frameworks of territorial actions, project-based teaching, and the autonomy of universities insert the universities in a multi-stakeholder dynamic. Indeed, the implementation of sustainable development comes in the form of local agendas, with communities engaging in them through various approaches and generating, through their role as financiers, partnerships between universities and local actors. These partnerships are often associative.

The educational activity is therefore formalized in part around these projects. The local translation of public policies of sustainable development will be based on associations that respond to local tenders. The studies to be performed will be helped by the student body and legitimized by the presumed expertise of faculty members and their institutional presence in the project. In return, the association which possesses the application experience of sustainable development approaches inserts the students in a concrete project of sustainable development, valued as a social integration of the university.

Given the context, associative competencies and projects from local territories engage local ESD in two very specific dominant forms in France. The first and most common, is moving towards eco-responsibility, or "good gestures" (sorting of waste, energy conservation, carpooling ...). It justifies its educational position from a point of view of citizen learning. The second form is the formalized project area, which responds to a directly utilitarian vision of sustainable development. It involves technical training such as spatial planning, tourism, management, community development, agriculture in ESD ... The fact of systematically relying on partner actors opens the way for justification of content by practices, and not by their scientific legitimacy, as shown by the analysis of curriculum evolutions of university degrees. In this sense, professional licenses for land planning constitute a telling example.

Case Study

The study presented here as an illustration concerns the curriculum evolution of degrees in the field of territory planning between 2001 and 2011. With the introduction of ESD at the university, a change is occurring in the display of degrees towards sustainable development over the last two four-year contracts. The issue is whether this is just a display, or if there is a real deeper curriculum change, which would transform the real curriculum.

The method of analysis follows a specific protocol, which includes the choice of degrees, the collection and diachronic comparison of course schedules, followed by a detailed analysis of specific teaching modules with the title "sustainable development".

The study focuses on French professional licenses 2 now labeled "sustainable planning of territories." Previously, the vast majority had a strong environmental display. 17 degrees were thus selected (All in France concerning Land Planning in University Institutes of Technology; see appendix). From these 17 degrees, a list of titles of the courses was established in 2001 and 2011. The various elements of the list of titles of the courses were grouped into categories. For example, "Basic statistics", "Elements of statistics," and "Data processing and statistics" were grouped in the category "statistics". But other groups were less straightforward. For example, should "sustainable development of rural areas" be classified as sustainable development or rural geography? In 8 cases, it was not possible to group the courses spontaneously. A telephone interview with the head of the degree or the module in question was conducted to clarify the real curriculum. This sometimes forced the sequencing of the content of courses in order to specify the distribution by categories.

After the regrouping of teachings by categories for 2001 and 2011, the volumes of class schedules that were actually given were associated to them. A diachronic type of a statistical treatment was then performed. Changes in the volume of schedules between the two dates, either positive or negative and greater than 7 hours were extracted and analyzed. To clarify these results, a closer analysis of the contents of the courses entitled "sustainable development" was conducted by telephone interview, and completed at the University of Provence with a questionnaire to stakeholders.

The results make it possible to identify the major curriculum changes that occurred between 2001 and 2011.They concern five main aspects:

1 -The introduction of a non-prescribed curriculum of ESD modules (+ 22 hours between 2001 and 2011, as an average)

The curricular precisions based on interviews and complementary surveys show that these courses are geared toward the know-how and behaviors to be implemented. They are the result of a multitude of stakeholders that present numerous applications for land planning. The capitalization of experiences that could be considered as renewable helps guide the following experiments. The course is often organized as a series of conferences. It also brings together stakeholders from various statuses such as teachers, lecturers, and professionals, and echoes the partnership trend of ESD at the University. The content of the course is normally the result of a tacit agreement among stakeholders, including a large thematic dispersion without reference to programs, and often without an effort of articulation. A questionnaire submitted in 2009 to 35 stakeholders in sustainable development modules (15 responses received) performed at the University of Provence actually shows that the spread of topics covered is important: the issue of "actors" comes out on top (6 occurrences), followed by "energy" (5) and "economy" (4); the theme of "environment" is absent. Also as part of the survey, in 80% of responses, the ESD does not refer to scientific fields, which confirms the order of importance of the choices in terms of the purpose of teaching. The most important are "Training of citizens" (14 occurrences), "Sharing of values" (13); "Explaining scientific phenomena" appears only in the fifth position (9). The orientation of the sustainable development course is constant in all degrees: you must inform to change individual behavior and the purpose of the module is a militant goalthe stakeholders being themselves all involved in movements for sustainable development. We are in education (liked to values), not in teaching (liked to knowledge), even if the school form is largely respected (conferences listed in the schedule, questionnaire at the end of module). But in feedback from stakeholders, it is perceived as an obstacle to the educational mission.

2 -There is the proliferation of specialized courses on sustainable development. They correspond to the acquisition of "good actions" taken in their professionalizing dimension. These include, for example, courses in "the development of sustainable tourism sectors," or "organization of alternative mobility services "(+8 hours between 2001 and 2011). The lessons of this type are usually the result of a single stakeholder, who develops advanced technical aspects in a particular field of sustainable development. They are in the field of engineering.

3 -The implementation of the principles of governance requires a strong adaptation to new skills related to managerial ability. This is also reflected in the emergence of methodological lessons, which pertain to project management and to all the phases of its implementation (+ 21 hours, as an average), as well as the diagnosis of the territory (+ 20 hours), or "communication skills" (+ 20 hours). They refer to the acquisition of new skills required by new jobs, such as "sustainable development trainers", "project leaders", "ESD project managers".... 4 -These changes are accompanied by an increase in the number of hours in law (+ 8 hours), which reflects the genesis of a new organizational and regulatory framework related to sustainable development.

5 -With the volume of lessons remaining broadly stable, new lessons are installed at the expense of others. Paradoxically, these are matters related to ecology and environmental science that lose importance, and to a lesser extent to the more general lessons. Indeed, when environmental protection was valued, knowledge of the environment constituted much of the knowledge to acquire strongly linked to well-identified scientific disciplines: biology, life sciences, geology, climatology, ecology, physical geography. These lessons are reduced on average by 50 hours per training between 2001 and 2011. In the same spirit, the lessons concerning the knowledge of societies, such as geography or sociology, decrease (-25 hours). The general lessons (English, applied mathematics) are also reduced by an average of 15 hours. All these changes show that school subjects and academic knowledge give way both to nondisciplinary content that is supposed to concern ESD in the broad sense, as well as to to transversal know-how. The changes also show than an emphasis is made on partnerships and political principles of organizational changes in governance. These changes call for a broader reflection on the educational logic and the educational issues surrounding their modifications.

The legitimacy of ESD, between knowledge and practices in an academic context

Questions about the legitimacy of ESD

ESD does not have the usual characteristics of disciplines; it is situated outside of the traditional form of teaching, as shown for example by the scientific paper presenting the research program ANR ED2AO : ESD, supports and barriers, 2008-2012(Lange, 2008). It provides the specificity of a form of education in France that is explicitly qualified as "education for": "ESD is part of all "educations for" which it combines most of the features [...] an interconnection of issues as much from the educational point of view (centering on the life experiences, skills, mixed nature, controversies , knowledge involved) as from the societal perspective (overlapping of environmental, health, social and economic issues); similarity of instructional approaches to promote their educational aspect and not their subjection to utilitarian objectives; the decisive and involved position of the subject in its social dimension, its values and its knowledge-representation systems, as much for the student as for the teacher. "

The "educations for" in France therefore have a special status, and a review of commonalities reveals four main features. They are thematic (the environment, health ...) and non-disciplinary, which distinguishes them from the standard model of academic content of a scientific nature. They have a close relationship with lively social issues (Legardez & Simonneaux, 2006) because they focus on problems that arise in society, and are a response to a form of social demand for education. They can be controversial. They place a high value on values: "ESD must form a scientific approach and foresight, enabling every citizen to make choices and commitments by supporting them with a lucid and informed reflection. It should also lead to a reflection on values, awareness of individual and collective responsibilities and the need for solidarity between intraand intergenerational territories "(Circular 2007-077, Ministry of National Education).

Moreover, in France, ESD conforms fairly well to the requirements of UNESCO. This organisation publishes a "compendium of good practices -ESD3 ", which states (p. 7): "Education is an essential tool in changing values and attitudes, behaviors and lifestyles, making them consistent with sustainable development." Some researchers are particularly critical of this requirement, thinking that ESD is only a utilitarian approach with economic goals (Sauvé 2006, Jickling 1992[START_REF] Alpe | Quelle est la légitimité des savoirs scolaires[END_REF][START_REF] Barthes | Éducation au développement durable et territoires ruraux. Problématique, projet de territoire et réduction fonctionnelle de l'enseignement[END_REF].

As a result, the scientific legitimacy of reference knowledge in ESD is not obvious. The contents borrow from many fields of science without a conceptual matrix, and to use the vocabulary of the sociology of science [START_REF] Vinck | Sociologie des sciences[END_REF], without a paradigmatic formation of the field, the latter being the subject of confrontation between experts to define the dominant orientation. They refer in addition to numerous serious social issues (Gayford 2002[START_REF] Oulton | Reconceptualizing the teaching of controversial issues[END_REF][START_REF] Simonneaux | Student socio-scientic reasoning on controversies from the viewpoint of education for sustainable developement[END_REF], as shown by the debates on climate change or GMOs.

With ESD being thematic, it is not a school subject and it has no formal curriculum. Therefore, there is no procedure for recognition of competencies to teach: is an"ESD teacher" means one who volunteers to become one, as there is no a priori validation. There are no programs or assessments of knowledge acquired and the national educational institution gives free rein to the development of local curricula. Therefore, there is no prescribed curriculum, which can serve as a basis for the construction of the legitimacy of content, from the perspective of an epistemology of school knowledge (Develay, 1998).

Ultimately, the legitimacy of ESD relies on four elements. On the activist position of the stakeholder: as there is no proof of competence, the stakeholder and the content of the intervention are legitimized «by conviction". This explains the multiplicity of stakeholders associations. It works on the possibility of modifying observable behavior and adequate assumptions. The content is therefore legitimized "by doing", but without social consensus on those practices that are the subject of many questions about their foundations ... It is organized by proximity to some of the lessons that are properly listed in the officially recognized disciplines: biology, geology and so on. The content is thus legitimized by "contagion," or external reference. Finally, the legitimacy of ESD is based on the supposed existence of a global system of reference, of a political-institutional and media-related nature, which would serve as conceptual matrix. The content is thus legitimized by the institutions which are themselves only partly legitimate.

The issue of distance from social practices

The denial of the distance (generally recognized as necessary in France in the teachings) between social practices and knowledge to teach is a common posture in ESD in France, as shown by courses based on examples of practices of stakeholders or steps towards eco-efficiency: how to organize the sorting of waste, carpooling, water conservation, etc ... Without taking a critical distance and by stressing the technical aspect, to the extent that the distancing of social situations is not done, teaching becomes here a technique of operationalization of procedures. Thus, it is no longer considered necessary to be able to formulate problems surrounding sustainable development in a methodological manner, despite being central to the formation of autonomous citizens. The step is then quickly taken on the risk of normative deviation. "Learning becomes an ethics course focusing on "political correctness" but is not liked any more to scientific knowledge" (Legardez, 2006).

Finally, the negation of the distance between knowledge and social practices crystallises debates about what is a project to set standards of conduct expected to be collectively accepted. Indeed, sustainable development adopts the image of collective responsibility. And all that refers to it appears as indisputably necessary to avoid the destruction of global equilibrium. This normative position induces a relativistic deviation from teachers that is a distortion of knowledge about socially valued attitudes without substantive analysis. These characteristics mean that ESD is thus positioned high on the scale of the risk of subject content to teach, because of the characteristics of the domain that are concerned: heterogeneity of scholarly reference fields, many scientific controversies, proximity to lively social issues, risk of activation of conflicting values, proximity to social practices.

Discussion of results and the international perspective

The international perspective shows differences and similarities that should be emphasized, comparing similar types of data.

In all cultural contexts, there is a tension between subject content to teach and intentions for training with respect to practical considerations. However, in an anglophone context, the focus is more readily on projects and case studies as levers to engage students in analyzing and learning about real, complex problems [START_REF] Steiner | Higher education for sustainability by means of transdisciplinary case studies: an innovative approach for solving complex, real-world problems[END_REF]. However in the French context, the project is more readily seen as a utilitarian approach with economic goals and thus the knowledge to acquire becomes determined by the market.

Interdisciplinarity is also seen in the Anglo-Saxon context as a dimension that allows students to analyze the environmental, social, economic, cultural and even ethical dimensions of these issues. Thus, the question of the integration of multidisciplinary and interdisciplinary analysis in training appears on a recurring basis [START_REF] Richter | Identifying Barriers to and Outcomes of Interdisciplinarity in the Engineering Classroom[END_REF][START_REF] Ashford | Major Challenges to Engineering Education for Sustainable Development: What Has to Change to Make It Creative, Effective, and Acceptable to the Established Disciplines?[END_REF]. In the French context, the discipline is rather seen as an obstacle to the implementation of ESD and interdisciplinarity as difficult to implement. More than just on interdisciplinarity, studies examine possible convergences between specific disciplines [START_REF] Vergnolle-Mainar C | Quelle convergence entre la géographie et l'histoire dans une perspective d'éducation au développement durable[END_REF] for the implementation of ESD.

The concern of fostering openness to divergent points of view and a capacity for dialogue, starting from different perspectives and points of view, is easier in an Anglo-Saxon context than in France, even if it acts mostly as an intention to practice and even if this refers also to debates. These aspects are found, for example when it comes to training engineers for sustainable development (Emilsson andLilje, 2008, Lehman, Christensen et al. 2008).

The issue of skills development comes up regularly, which creates a problem in the choice of skills to develop, ways to teach and evaluate, and with very different answers according to the contexts.

It should be noted that the training for the ethical analysis of issues raised by sustainable development or ethical decision-making is more of an Anglo-Saxon specificity. It is seen as another challenge to the implementation of ESD in the context of university education (El-Zein, Airey et al. 2008), while the ethical considerations, even if they exist, are more marginal in France.

Conclusion

To characterize the specificity of ESD in the French university context of professional license programs, our case study highlights a centering on a non-prescribed curriculum that is centered mainly on good actions and eco-efficiency, and the contents are not derived from scientific knowledge. With the integration of sustainable development in programs, there is a decrease in disciplinary knowledge to focus on the acquisition of principles of governance related to sustainable development and project management. This change can be experienced in the French cultural space as a utilitarian education imposed by international institutions. No mention is made in these training programs regarding the integration of ethical concerns on sustainable development issues, nor on the question of engagement in the sense of critical education. We do not find any reflection on interdisciplinary training as a way to represent oneself and to analyze sustainable development considerations or as a work method that would allow the crossing of divergent interests and points of view in analysis and decision making. In this way, the integration of ESD in the French university context seems to stand out from the principles emphasized in Anglo-Saxon cultural contexts.

Bibliography

This declaration can be consulted on the internet : http://www.ulsf.org/pdf/French_TD.pdf

By professional license, we mean an undergraduate university program that is completed in three years and leads to a professional practice. Most of these licenses are done in the Instituts Universitaires Technologiques (University Institutes of Technology). The analysis will be of the third year.

http://unesdoc.unesco.org/images/0018/001812/181270f.pdf

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Richard Darbéra

THE END OF THE TAXIMETER? OR THE END OF THE TAXI? 1

Smartphone apps will render obsolete the economic justifications for setting taxis quotas and for regulating taxi fares since the borderline between street hail (a taxicab monopoly) and telephone booking will be blurred.

TWO QUESTIONS AND A DREAM (OR NIGHTMARE?) People who request a taxi want to go from A to B.

Why do taxis have a mandatory rooftop light? Because when the light is on, people can see from the sidewalk that the taxi is available, so they can hail it.

Why do taxis have a mandatory taximeter? Since the client who boards the taxi cannot know in advance how much the ride will cost him, the taximeter is here to guaranty the fare will be fair.

Introducing price competition in the metered taxi supply is tricky. This has been tried in the times of the horse cabs in Paris with three colours flags. It did not work out too well and was abandoned. Even now, with up-to-date technology, is does not work so well in Stockholm or in Oslo. Some time in the future, I am standing on a sidewalk somewhere in Apple City or in Google Town. I take my iPhone and tell Siri I want a taxi to the airport or to the closest Starbucks. Siri selects half a dozen vehicles and shows me, for each one of them, the price of the ride, the type of vehicle and how long I will have to wait for it to pick me up. I can choose the cheapest, or the largest (van), or the fastest (motorbike) or the cleanest (electric car). I can also choose according to the rating of the driver.

Then I can see the vehicle coming to me on a map, and when it is close enough, the screen of my iPhone exhibit a distinct code I can show to the vehicles approaching so the driver knows I am the person who requested the ride.

No rooftop light, no taximeter, and probably no money since the app operator will debit my credit card account and pay the taxi directly. While sipping my coffee at Starbucks or waiting in line at the airport counter, I can use my iPhone and give a grade to the ride I just had.

After dropping me at Starbucks, the taxi driver tells its on-board terminal that he is available for a new assignment. According to the spot market situation (supply, demand, congestion) provided in real time by his terminal, he can choose the rate at which he will auction his next service.

NO ROOFTOP LIGHT, NO TAXIMETER. NO REGULATION?

Is the system described above safe? Is it stable?

To answer these questions it is necessary to answer first another question: is the taxi app business a natural monopoly? It probably is, just as the radio-taxi dispatch is. When seeking a taxi, customers dial the call centre with the largest radio-taxi fleet. Conversely, drivers seek affiliation with the call centre that gets most calls. What works with the call centres of today will probably work as well with the taxi apps of the future for the same reason. Entering the taxi app business requires an investment in software (~ 30 man-months) and in advertising. In a mature market, attracting both customers and drivers requires a strong competitive advantage in terms of price and quality and time to make potential customers aware of it, i.e. it entails loosing money for several years, just like Amazon did.

Thus the first task for the regulator is to ensure that no app operators can reach a monopoly position, at least at the local level.

What about the driver's business?

Although the apps operators will not like it, it seems reasonable for drivers to get affiliated to two or more apps. It is however easy for the app operator to spot the driver that switches off too often before getting a new assignment. App operators will probably forbid it. App operators will also ban from their fleet the drivers who consistently get bad ratings from the customers for inappropriate or dangerous behaviour. Being rejected by all the app operators of the city might take time. Not to mention the fact that drivers may change location from one city to the other.

Since app operators are not able to prevent that, the second task of the regulator would be to control both drivers and vehicles, just like Transport for London started regulating the minicab business back in 1998. Another reason for regulating drivers' access to the profession is that apps operators may have little incentive (or legal capacity) to check on the drivers' criminal record and physical fitness.

Controlling drivers and vehicles has a cost. It is thus reasonable for the regulator to charge a fee. Another reason to charge a fee is that entry in the driver's business is cheap. It is thus probable that what happened in the four largest cities of the Netherlands right after deregulation would happen here also: massive entry and exit from the business.

Will there be too many cars, double-parked, and waiting for calls? In a city with congestion pricing and efficient parking pricing, this should not be a problem. The regulators might find useful however to create special parking facilities like taxi ranks in places with high demand, where customers resistant to smartphones could get rides the traditional way.

Taxi ranks and airports (and other places where massive demand meets massive supply) raise a specific question: how to set the prices of the rides that cannot be auctioned on the app network because of limited physical space for customers and vehicles to meet? The answer probably is the solution that was invented back in the 17 th century when the first coaches gathered around May Pole in London in or around the Hotel Saint Fiacre in Paris, and which is still in use in many airports around the world: a fixed price from zone to zone. This price can be advertised on a billboard at the taxi rank. It is the role of the owner of the premises (e.g. the airport authority) to only allow on the ranks the vehicles that accept the system and meet specific quality criteria.

A ROLE FOR THE CONSUMERS ASSOCIATIONS

App operators might turn a blind eye to whether the driver is really operating a registered car or not. Unless it has real time knowledge of the position of all the vehicles on duty, as the Taxi and Limousine Commissions presently has in New York City, it is difficult (or quite costly) for the regulator to check a good compliance to the vehicle requirements.

Here customers can play a role by reporting vehicles or drivers who do not exhibit the required documents in the vehicle.

Many other questions remain about the practicability of the system, e.g. what about the non-registered customers like the tourists or what about price competition at taxi ranks, but the most interesting question, at least in the short run, is how such a system could ever come about given the strategies of the various actors involved: established radio-taxi dispatch operators, taxi companies, taxi drivers, taxi app start-ups, Google-like outsiders, etc. But that's another story, as Kipling said.

Paper presented at the 5th International IRU Taxi Forum Cologne, Germany, 10 November

2 Institut pour la Ville en Mouvement (Cities on the move) Research Project, Paris