Aurélie Hemonnet-Goujot

Pierre Valette-Florence
email: pierre.valette-florence@univ-grenoble-alpes.fr

From product design value perception to luxury brand love: An integrated framework

Keywords: Product Design, Value Theory, Consumer-Brand Relationship, Brand Love

"All you need is love". From product design value perception to luxury brand love: An integrated framework

Introduction

Product design is at the heart of luxury brands; Hermès is well known for its Birkin bag, Porsche for its 911 car, and Berluti for its Richelieu shoes. Historically, these brands have introduced iconic product design to strongly fuel brand love, with further examples including the Hermès Cape Cod watch and Kelly double tour bracelet, the Porsche Cayenne and Macan, and Berluti's Andy loafers.

Product design is intrinsically linked to brand building, and is often cited when defining luxury in relation to an object's beauty, rarity, timelessness, quality, and sensuality [START_REF] Kapferer | The New Strategic Brand Management: Creating and Sustaining Brand Equity[END_REF]; however, consumer perception of product design value and brand evaluation are usually addressed separately [START_REF] Melewar | Global design, marketing and branding: introduction to the special issue[END_REF]). Yet products are integral to the identity of brands (particularly luxury brands) and reflect the complete experience customers have with them [START_REF] Keller | Conceptualizing, Measuring, and Managing Customer-Based Brand Equity[END_REF][START_REF] Keller | Brands and branding: Research findings and future priorities[END_REF][START_REF] Wiedmann | Measuring consumers' luxury value perception: a cross-cultural framework[END_REF].

To date, the literature on product design has focused on the antecedents of product design value perception (PDVP), such as the need for status, the influence of the self-expressive dimension [START_REF] Han | Signaling status with luxury goods: The role of brand prominence[END_REF][START_REF] Kumar | Beyond form and function: Why do consumers value product design[END_REF], or the specific consequences of PDVP for marketplace success [START_REF] Chitturi | Delight by Design: The Role of Hedonic Versus Utilitarian Benefits[END_REF][START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF][START_REF] Jindal | Designed to Succeed: Dimensions of Product Design and Their Impact on Market Share[END_REF][START_REF] Liu | The Effects of Products' Aesthetic Design on Demand and Marketing-Mix Effectiveness: The Role of Segment Prototypicality and Brand Consistency[END_REF]. In marketing research, most studies have focused on the influence of PDVP on consumer choice and responses [START_REF] Bloch | Seeking the Ideal Form: Product Design and Consumer Response[END_REF][START_REF] Celhay | Package Graphic Design: Investigating the Variables that Moderate Consumer Response to Atypical Designs[END_REF][START_REF] Chitturi | Delight by Design: The Role of Hedonic Versus Utilitarian Benefits[END_REF][START_REF] Creusen | The Different Roles of Product Appearance in Consumer Choice[END_REF][START_REF] Crilly | Seeing things: consumer response to the visual domain in product design[END_REF][START_REF] Landwehr | The tipping point of design: How product design and brands interact to affect consumers' preferences[END_REF], or the influence of PDVP on brand perception, such as brand image, brand impression, brand recognition, and brand categorization [START_REF] Karjalainen | Designing Visual Recognition for the Brand[END_REF][START_REF] Kreuzbauer | Embodied Cognition and New Product Design: Changing Product Form to Influence Brand Categorization[END_REF][START_REF] Pantin-Sohier | The influence of the product package on functional and symbolic associations of brand image[END_REF].

However, the emphasis of this prior research has mainly been on non-luxury goods (Table 1). While the appeal of product design is viewed as highly important for the luxury industry [START_REF] Dion | Retail luxury strategy: assembling charisma through art and magic[END_REF][START_REF] Dubois | Consumer rapport to luxury: Analyzing complex and ambivalent attitudes[END_REF] and an integral part of what defines a brand [START_REF] Keller | Conceptualizing, Measuring, and Managing Customer-Based Brand Equity[END_REF], little is yet known, to our knowledge, of how PDVP influences consumer-luxury brand relationships; in particular, how it elicits passionate feelings towards luxury brands, i.e., brand love [START_REF] Batra | Brand love[END_REF][START_REF] Carroll | Some antecedents and outcomes of brand love[END_REF]. Moreover, few prior studies have focused on the emotions linked to luxury consumption, conducting either broad investigations into hedonism [START_REF] Hagtvedt | The broad embrace of luxury: Hedonic potential as a driver of brand extendibility[END_REF], or even larger investigations into the emotional spectrum linked to purchasing luxury items in a retail context [START_REF] Kim | Customer emotions and their triggers in luxury retail: Understanding the effects of customer emotions before and after entering a luxury shop[END_REF]. By contrast, our research explicitly explores specific positive feelings elicited by brand love as a direct consequence of PDVP. Although some papers have focused on the influence of PDVP on consumer-brand relationships, particularly brand affection and brand attitude [START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF][START_REF] Kumar | Enhancing Consumers' Affection for a Brand Using Product Design[END_REF], the mechanisms linking product-level perception of design to brand-level attitudes are still unclear [START_REF] Keller | Brands and branding: Research findings and future priorities[END_REF]Kumar et al., 2015). To date, an overarching view encompassing antecedents of PDVP and its influence on consumer-luxury brand relationships is still lacking.

Insert Table 1

This paper aims at filling this gap in the literature by addressing the following research question: What are the antecedents and consequences of product design value perception for luxury brands?

Based on value theory and the results of two quantitative studies (N1 = 276 and N2 = 249) analyzed using a partial least squares (PLS) approach, this paper contributes to the literature by proposing an integrated framework of the PDVP antecedents and consequences for consumer-luxury brand relationships. On this basis, the current study first investigates the antecedents and consequences of PDVP, before focusing on the mediators and one consumerdependent moderator. Building on the definition of PDVP as the perception of the functional, aesthetic, and symbolic values conveyed by a product [START_REF] Candi | Consumer responses to functional, aesthetic and symbolic product design in online reviews[END_REF][START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF][START_REF] Kumar | Beyond form and function: Why do consumers value product design[END_REF]Kumar et al., 2015), this paper first highlights the influence of social and individual drivers on PDVP. Second, it reveals the mechanisms through which product-level value perception of design influences brand-level relationships for luxury brands. In particular, this paper explains how PDVP enhances luxury brand love through the full mediating roles of brand equity and brand identification, and the moderating role of design acumen. Third, it reveals that luxury brand love leads to greater willingness to pay a price premium (WTPP).

The paper is organized as follows. We first present our conceptual framework, built on value theory, to show how PDVP relates to luxury brands (Section 2). We then specify the research hypotheses and expected results (Section 3). The research method and data are then presented (Section 4), followed by the empirical findings (Section 5). The final section (Section 6) discusses the study's implications, both theoretical and practical. It also highlights the limitations, along with potential avenues for future research.

Theoretical framework

Value theory

Value theory addresses a common concern of marketing managers: how to create and deliver superior consumer value [START_REF] Woodruff | Customer value: the next source for competitive advantage[END_REF]. Zeithaml (1988, p. 14) defines value as "the consumer's overall assessment of the utility of a product based on perceptions of what is received and what he is given." The theory has been used to study value through two different lenses. The first approach deals with global value as an evaluative judgment resulting from a comparison between the benefits and sacrifices associated with the purchase of a product [START_REF] Grewal | The effects of price-comparison advertising on buyers' perceptions of acquisition value, transaction value, and behavioral intentions[END_REF][START_REF] Zeithaml | Consumer perceptions of price, quality, and value: a means-end model and synthesis of evidence[END_REF]. Such judgment is based on a comparative process that can operate at two levels: intra-product and inter-product [START_REF] Sinha | An integrated approach toward the spatial modeling of perceived customer value[END_REF]. The second approach derives from the experiential literature [START_REF] Holbrook | The experiential aspects of consumption: consumer fantasies, feelings, and fun[END_REF] and relates to usage value, based on a consumption experience. In this approach, value is perceived neither as a characteristic of the object nor as a characteristic of the individual, but rather as the result of the interaction between the two [START_REF] Holbrook | Consumer value: a framework for analysis and research[END_REF]. As PDVP is based not only on the nature of the object [START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF] but also on the characteristics of the individual [START_REF] Han | Signaling status with luxury goods: The role of brand prominence[END_REF][START_REF] Kumar | Beyond form and function: Why do consumers value product design[END_REF] and on experience [START_REF] Bloch | Seeking the Ideal Form: Product Design and Consumer Response[END_REF], our research adopts the second approach.

According to [START_REF] Holbrook | Consumer value: a framework for analysis and research[END_REF], two distinct types of drivers are associated with product value: (1) interpersonal social drivers; and (2) utilitarian individual drivers. The former comes from social psychology, in which it is posited that individuals feel the need to be perceived as both "similar and different" [START_REF] Maslach | Individuation: Conceptual analysis and assessment[END_REF][START_REF] Snyder | Abnormality as a positive characteristic: The development and validation of a scale measuring need for uniqueness[END_REF]. In this approach, consumers form associations between reference groups and the brands they use, and transfer those meanings to their self-concept or possible self [START_REF] Escalas | Self-construal, reference groups, and brand meaning[END_REF]. The latter refers to the extent to which a product fits the individual's preferences. From a social identity perspective, consumers use a brand for self-definition when that brand satisfies self-motives such as self-enhancement (by reflecting favorably on oneself), selfconsistency, or self-differentiation [START_REF] Ashforth | Social identity theory and the organization[END_REF][START_REF] Bhattacharya | Consumer-company identification: A framework for understanding consumers' relationships with companies[END_REF][START_REF] Tajfel | The Social Identity Theory of Intergroup Behavior Psychology of Intergroup Relations[END_REF]. These two distinct types of drivers (social and individual) are associated with product design value, and have been used in the literature on luxury to identify determining factors in the consumption of luxury goods. Such studies make a particular distinction between external, social factors such as people's judgment [START_REF] Groth | The exclusive value principle: the basis for prestige racing[END_REF] and internal, emotion-generated factors [START_REF] Vigneron | Measuring perceptions of brand luxury[END_REF][START_REF] Wiedmann | Measuring consumers' luxury value perception: a cross-cultural framework[END_REF]. In addition to price, advertising, and retail, product design appears to be an important aspect of luxury brand evaluation [START_REF] Kapferer | The New Strategic Brand Management: Creating and Sustaining Brand Equity[END_REF]). Yet, to our knowledge, no research has managed to build on those two drivers (social and individual) to provide a better understanding of how PDVP influences the consumer-luxury brand relationship.

Product design value perception and consumer-luxury brand impression

When dealing with value theory in luxury, the literature shows that luxury brand value is built on three distinct dimensions: functional, experiential, and symbolic [START_REF] Berthon | Aesthetics and ephemerality: observing and preserving the luxury brand[END_REF][START_REF] Shukla | They are not all same: variations in Asian consumers' value perceptions of luxury brands[END_REF]. The functional dimension is the physical manifestation of the brand characterized by the quality of the material and craftsmanship. The experiential dimension pertains to sensations and feelings toward the brand. The symbolic dimension relates to social signals associated with brand meaning.

Echoing the literature on luxury, PDVP is the perception of the functional, aesthetic, and symbolic values conveyed by a product [START_REF] Candi | Consumer responses to functional, aesthetic and symbolic product design in online reviews[END_REF][START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF][START_REF] Kumar | Beyond form and function: Why do consumers value product design[END_REF]Kumar et al., 2015). Building on the definition of product design as "a set of constitutive elements of a product that consumers perceive and organize as a multidimensional construct comprising the three dimensions of aesthetics, functionality, and symbolism2 " (Homburg et al., 2015, p. 44), PDVP is thus considered a subjective construct by the literature. The perceived attributes of a product affect consumers' beliefs about the product and the brand [START_REF] Bitner | Servicescapes: The impact of physical surroundings on customers and employees[END_REF][START_REF] Bloch | Seeking the Ideal Form: Product Design and Consumer Response[END_REF][START_REF] Solomon | The role of products as social stimuli: A symbolic interactionism perspective[END_REF], and influence their judgments [START_REF] Crilly | Seeing things: consumer response to the visual domain in product design[END_REF]. Such perceptions may also be influenced by the context of consumption and by consumer characteristics [START_REF] Bloch | Seeking the Ideal Form: Product Design and Consumer Response[END_REF][START_REF] Crilly | Seeing things: consumer response to the visual domain in product design[END_REF], such as design acumen [START_REF] Bloch | Individual differences in the centrality of visual product aesthetics: Concept and measurement[END_REF][START_REF] Kumar | Beyond form and function: Why do consumers value product design[END_REF].

The functional dimension of PDVP reflects the consumer's perception of a product to fulfill its purpose [START_REF] Bloch | Product design and marketing: Reflections after fifteen years[END_REF][START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF]. From a product perspective, luxury brands are frequently defined in terms of their high transaction value, distinctiveness, exclusivity, and craftsmanship [START_REF] Fionda | The anatomy of the luxury fashion brand[END_REF][START_REF] Kapferer | The New Strategic Brand Management: Creating and Sustaining Brand Equity[END_REF]. In the literature on luxury, the functional dimension of luxury products refers to the core benefits that determine the consumer's impression of the brand, such as product quality, uniqueness, usability, reliability, and durability [START_REF] Sheth | Why we buy what we buy: A theory of consumption values[END_REF][START_REF] Wiedmann | Measuring consumers' luxury value perception: a cross-cultural framework[END_REF]. For luxury brands, product design-in particular, the perceived excellence of a product-bolsters credibility [START_REF] Fionda | The anatomy of the luxury fashion brand[END_REF].

Product design has historically been associated with the aesthetic dimension, i.e., the perceived appearance and beauty of a product [START_REF] Bloch | Product design and marketing: Reflections after fifteen years[END_REF][START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF] that strengthens the emotional value consumers attach to it [START_REF] Bloch | Individual differences in the centrality of visual product aesthetics: Concept and measurement[END_REF][START_REF] Holbrook | The experiential aspects of consumption: consumer fantasies, feelings, and fun[END_REF][START_REF] Norman | Emotional design: Why we love (or hate) everyday things[END_REF]. While expressing brand personality, aesthetic design enhances consumer delight, and appeals to the senses mainly through visual and tactile features, contributing to development of the hedonic product qualities that trigger delight [START_REF] Chitturi | Delight by Design: The Role of Hedonic Versus Utilitarian Benefits[END_REF][START_REF] Rindova | When Is a New Thing a Good Thing? Technological Change, Product Form Design, and Perceptions of Value for Product Innovations[END_REF]. For luxury brands, product design can give a recognizable style based on preservation of the brand's history, as communicated through references to archive collections, or through the integration of a visual artistic dimension that positively influences luxury brand impression [START_REF] Fionda | The anatomy of the luxury fashion brand[END_REF][START_REF] Hagtvedt | Art infusion: The influence of visual art on the perception and evaluation of consumer products[END_REF].

In addition to the functional and aesthetic dimensions, the literature on product design has shed light on a third dimension-the symbolic dimension [START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF][START_REF] Verganti | Design, Meanings, and Radical Innovation: A Metamodel and a Research Agenda[END_REF]. The symbolic dimension refers to the perceived message a product communicates regarding a consumer's self-image to both themselves and to others on the basis of visual elements [START_REF] Aaker | The malleable self: The role of self-expression in persuasion[END_REF][START_REF] Bloch | Product design and marketing: Reflections after fifteen years[END_REF]. Separate from a product's styling, the symbolic value of a product (i.e., its meaning) is what matters to the user, since it addresses the consumer's affective and sociocultural needs [START_REF] Verganti | Design, Meanings, and Radical Innovation: A Metamodel and a Research Agenda[END_REF]. According to the [START_REF] Belk | Possessions and the extended self[END_REF] theory of the extended self, the possession of luxury products serves as a symbolic marker of group membership, with product design being intrinsically linked to such symbolism [START_REF] El Amri | Perceived design affordance of new products: Scale development and validation[END_REF][START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF][START_REF] Verganti | Design, Meanings, and Radical Innovation: A Metamodel and a Research Agenda[END_REF]. The symbolic dimension of product design may help luxury brand consumers to classify or distinguish themselves in relation to others, but they may also try to integrate the symbolic meaning into their own identity [START_REF] Holt | How consumers consume: A typology of consumption practices[END_REF][START_REF] Vigneron | Measuring perceptions of brand luxury[END_REF]. Importantly, the meanings of objects tend to transfer to those who acquire and utilize them; a process that can help individuals in their identity work [START_REF] Ahuvia | Beyond the extended self: Loved objects and consumers' identity narratives[END_REF][START_REF] Belk | Possessions and the extended self[END_REF]. The symbolic association drives a luxury brand choice to send meaningful signals to others [START_REF] Berger | Subtle signals of inconspicuous consumption[END_REF][START_REF] Shukla | They are not all same: variations in Asian consumers' value perceptions of luxury brands[END_REF].

Product design is often the first point of contact between the consumer and the brand, and is commonly used by the consumer as a heuristic to evaluate [START_REF] Brunner | Impact of symbolic product design on brand evaluations[END_REF], and form impressions of the brand [START_REF] Bloch | Seeking the Ideal Form: Product Design and Consumer Response[END_REF][START_REF] Creusen | The Different Roles of Product Appearance in Consumer Choice[END_REF][START_REF] Karjalainen | It looks like a Toyota: Educational approaches to designing for visual brand recognition[END_REF]. More precisely, this literature review shows that the holistic construct of PDVP (comprising the functional, aesthetic, and symbolic dimensions) helps consumers to form luxury brand impressions and to connect with them. While PDVP is strongly linked to luxury brands, and product-level value perception is shown to influence brand-level consumer relationships (Kumar et al., 2015), it is still unclear how PDVP influences luxury brand-level attitudes; the research stream still lacks an integrated framework of the PDVP antecedents and consequences for consumer-luxury brand relationships.

Hypotheses

Influence of social and individual drivers on product design value perception

According to the value theory identified in the conceptual framework, external factorsin particular, interpersonal social drivers-are associated with product value. Such a notion is crucial for luxury goods: consumption of their products serves as a strong social function [START_REF] Wiedmann | Measuring consumers' luxury value perception: a cross-cultural framework[END_REF], with product design acting as a signal of belonging to a certain social group [START_REF] Han | Signaling status with luxury goods: The role of brand prominence[END_REF]. Furthermore, social desirability has been shown to drive consumer choice by increasing product likability [START_REF] Rindfleisch | Explaining the familiarity-liking relationship: mere exposure, information availability, or social desirability?[END_REF]. The conspicuous nature of product design means it is more observable and thus plays an important role in making a product more socially desirable, in turn enabling consumers to fulfill social objectives such as increasing perceived social status [START_REF] Noble | Using product design strategically to create deeper consumer connections[END_REF][START_REF] Chin | Bootstrap cross-validation indices for PLS path model assessment[END_REF] or improving self-esteem.

Consumers are thus influenced by both their own social group [START_REF] Bearden | Reference group influence on product and brand purchase decisions[END_REF][START_REF] Whittler | Model's race: A peripheral cue in advertising messages[END_REF] and those they aspire to emulate [START_REF] Escalas | You are what they eat: The influence of reference groups on consumers' connections to brands[END_REF], 2005).

For luxury brands, the social dimension refers to the perceived utility that individuals acquire when consuming products recognized within their own social groups [START_REF] Bearden | Reference group influence on product and brand purchase decisions[END_REF][START_REF] Vigneron | A review and a conceptual framework of prestigeseeking consumer behavior[END_REF][START_REF] Norman | Emotional design: Why we love (or hate) everyday things[END_REF]). People's need for status can be defined as a "tendency to purchase goods and services for the status or social prestige value that they confer on their owners" (Eastman, Goldsmith, & Flynn, 1999, p. 41). As superior product design indicates social desirability [START_REF] Rindfleisch | Explaining the familiarity-liking relationship: mere exposure, information availability, or social desirability?[END_REF] and social status [START_REF] Noble | Exploring the appeal of product design: A grounded, value-based model of key design elements and relationships[END_REF], we posit: H1: For luxury brands, social drivers positively influence product design value perception.

Although social drivers play an important role, individual drivers also contribute to product value. To date, numerous researchers have called for a distinction between socially oriented and personally oriented luxury consumers [START_REF] Tsai | Impact of personal orientation on luxury-brand purchase value[END_REF][START_REF] Wiedmann | Measuring consumers' luxury value perception: a cross-cultural framework[END_REF][START_REF] Wong | Personal taste and family face: Luxury consumption in Confucian and Western societies[END_REF], and trace the origins of those orientations back to a person's self-concept as being either interdependent or independent [START_REF] Markus | Culture and the self: Implications for cognition, emotion, and motivation[END_REF][START_REF] Triandis | The self and social behavior in differing cultural contexts[END_REF].

Individual drivers reflect consumers' desire to express their extended selves [START_REF] Belk | Possessions and the extended self[END_REF][START_REF] Holt | Poststructuralist lifestyle analysis: Conceptualizing the social patterning of consumption in postmodernity[END_REF][START_REF] Kleine | Mundane consumption and the self: A social-identity perspective[END_REF]. In the literature on luxury, individual drivers are characterized as a customer's personal orientation toward luxury consumption [START_REF] Wiedmann | Measuring consumers' luxury value perception: a cross-cultural framework[END_REF]. Consumers' motivations for luxury consumption reflect not only social or signaling considerations but also individual, personal considerations, such as materialism [START_REF] Richins | A consumer values orientation for materialism and its measurement: Scale development and validation[END_REF], hedonism, or self-identity [START_REF] Holbrook | The experiential aspects of consumption: consumer fantasies, feelings, and fun[END_REF][START_REF] Vigneron | Measuring perceptions of brand luxury[END_REF]. Thus, consumers may use luxury brands for self-presentation and selfexpression purposes, as well as to support and develop their own identity [START_REF] Han | Signaling status with luxury goods: The role of brand prominence[END_REF][START_REF] Janssen | Should luxury brands say it out loud? Brand conspicuousness and consumer perceptions of responsible luxury[END_REF]. Social identity theory establishes three underlying individual motives: self-enhancement, self-consistency, and self-differentiation [START_REF] Bhattacharya | Consumer-company identification: A framework for understanding consumers' relationships with companies[END_REF][START_REF] Wolter | Symbolic drivers of consumerbrand identification and disidentification[END_REF]. Self-enhancement is driven by individuals seeking to gain prestige, especially by consuming luxury goods. Self-consistency is driven by the congruity between the consumer's self-image and the image of the product [START_REF] Sirgy | Using self-congruity and ideal congruity to predict purchase motivation[END_REF]. Self-differentiation motives are driven by the need to be distinctive from others. Since objects (including product design) mirror an individual's personality, distinctiveness, and enhancement, they contribute to shaping that individual's identity. Individuals are thus more likely to perceive the product design value, since objects have the power to make individuals feel special [START_REF] Ahuvia | Beyond the extended self: Loved objects and consumers' identity narratives[END_REF][START_REF] Belk | Possessions and the extended self[END_REF]. We therefore posit: H2: For luxury brands, individual drivers positively influence product design value perception.

The influence of product design value perception on brand love

While much marketing research to date has focused on understanding the relationship between product design and consumer response [START_REF] Bloch | Seeking the Ideal Form: Product Design and Consumer Response[END_REF][START_REF] Chitturi | Delight by Design: The Role of Hedonic Versus Utilitarian Benefits[END_REF][START_REF] Creusen | The Different Roles of Product Appearance in Consumer Choice[END_REF][START_REF] Page | An Investigation of the Processes by which Product Design and Brand Strength Interact to Determine Initial Affect and Quality Judgments[END_REF], or between product design and brand perception [START_REF] Karjalainen | Designing Visual Recognition for the Brand[END_REF][START_REF] Pantin-Sohier | The influence of the product package on functional and symbolic associations of brand image[END_REF], few papers have concentrated on the influence of product design on the consumer-brand relationship [START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF]Kumar et al., 2015). Kumar et al. (2015) make a theoretical connection between design-based values at the product level and affective brand-level relational outcomes. They show that PDVP is positively linked to brand affection. While opening a new and fertile area for research, their work is still exploratory and has a number of limitations. In the context of PDVP and luxury brands, a relational variable other than brand affection could be considered: that of brand love. Brand love, defined as "passionate emotional attachment" (Carroll & Ahuvia, 2006, p. 81), is higher for brands with hedonic and symbolic benefits [START_REF] Carroll | Some antecedents and outcomes of brand love[END_REF]. As such, this construct is particularly appropriate for luxury brands. The aesthetic dimension of PDVP is shown to trigger emotions and hedonism, especially for luxury brands [START_REF] Chitturi | Delight by Design: The Role of Hedonic Versus Utilitarian Benefits[END_REF][START_REF] Liu | The Effects of Products' Aesthetic Design on Demand and Marketing-Mix Effectiveness: The Role of Segment Prototypicality and Brand Consistency[END_REF]. Furthermore, the symbolic dimension of PDVP creates meanings that are shown to enrich interactions between the brand and the consumer, and determine the relationship quality, such as love [START_REF] Fournier | Consumers and their brands: Developing relationship theory in consumer research[END_REF].

The literature on consumer-brand relationships identifies that feelings of love toward objects can trigger brand love [START_REF] Ahuvia | Beyond the extended self: Loved objects and consumers' identity narratives[END_REF][START_REF] Batra | Brand love[END_REF]. Product quality perception, including the functional and practical dimensions, influences brand love [START_REF] Bagozzi | Brand love: development and validation of a practical scale[END_REF]. Moreover, product design that resonates more affectively with consumers is better able to transfer that relationship equity to the brand it embodies [START_REF] Bhattacharya | Consumer-company identification: A framework for understanding consumers' relationships with companies[END_REF]. While product design tends to generate strong emotional responses, no research, to our knowledge, has established a link between product design and brand love. Yet the brand love construct [START_REF] Batra | Brand love[END_REF] is referred to as a high-order factor of three variables: (1) passion-driven behaviors and a passionate desire to use, which can be enhanced by product use and by its functional, aesthetic, and symbolic dimensions; (2) self-brand integration based on desired brand identity, which can be expressed through product design, as mentioned previously; and (3) positive emotional connection, which can also be triggered by product design [START_REF] Bloch | Seeking the Ideal Form: Product Design and Consumer Response[END_REF][START_REF] Rindova | When Is a New Thing a Good Thing? Technological Change, Product Form Design, and Perceptions of Value for Product Innovations[END_REF].

Based on the aforementioned relationship between product design and brand love, and with perceptions of value at the product level taken to be antecedents of consumers' relationships with brands [START_REF] Keller | Conceptualizing, Measuring, and Managing Customer-Based Brand Equity[END_REF], one could posit that PDVP is not only linked to brand affection-defined in relation to passion and pride by Kumar et al. (2015)-but also positively linked to brand love. We therefore posit: H3: For luxury brands, product design value perception positively influences brand love.

The mediating roles of brand equity and brand identification

While the research of Kumar et al. (2015) does reveal a direct link between PDVP and brand affection, the literature on branding suggests that the consumer-brand relationship is more complex in that the different components of the consumer-brand relationship are linked in a chain [START_REF] Fournier | Consumers and their brands: Developing relationship theory in consumer research[END_REF].

As an integral part of what defines a brand, product design is also an important driver of brand equity [START_REF] Keller | Conceptualizing, Measuring, and Managing Customer-Based Brand Equity[END_REF]. In particular, in line with value theory, product design-through its perceived quality-triggers a consumer's subjective judgment of a product's quality or superiority [START_REF] Zeithaml | Consumer perceptions of price, quality, and value: a means-end model and synthesis of evidence[END_REF]; a process that can be deemed an antecedent of brand equity [START_REF] Yoo | An examination of selected marketing mix elements and brand equity[END_REF]. Brand equity is defined as a preference for, attachment to, and loyalty to a particular brand [START_REF] Yoo | An examination of selected marketing mix elements and brand equity[END_REF]. Product design enables consumers to identify as belonging to a certain social group. As such, the consumption of products recognized within one's own social groups affects brand evaluation and preference, leading to the tendency to purchase or consume certain luxury brands [START_REF] Bearden | Reference group influence on product and brand purchase decisions[END_REF][START_REF] Vigneron | Measuring perceptions of brand luxury[END_REF]. Product design also adds value to a product by increasing the quality of the usage experiences associated with it [START_REF] Bloch | Seeking the Ideal Form: Product Design and Consumer Response[END_REF], leading to enjoyment and emotional attachment. This creation of a new experience through product design has a positive impact on brand equity [START_REF] Keller | Brands and branding: Research findings and future priorities[END_REF]. As product design influences preference, attachment, and loyalty, we posit: H4: For luxury brands, product design value perception positively influences brand equity.

Brands in product categories that are perceived as more hedonic, compared to utilitarian, and that offer strong symbolic benefits are more likely to strengthen consumers' attachment [START_REF] Carroll | Some antecedents and outcomes of brand love[END_REF]. Emotional attachment consists of three dimensions (affection, passion, and connection) [START_REF] Thomson | The ties that bind: Measuring the strength of consumers' emotional attachments to brands[END_REF] and brand love represents the highest degree of passion that one can have for a brand [START_REF] Carroll | Some antecedents and outcomes of brand love[END_REF]. Positive feelings generated by PDVP strengthen emotional bonds between the consumer and the brand. Furthermore, consumers who strongly value a brand through a strong emotional attachment and positive feelings are expected to feel stronger brand love [START_REF] Batra | Brand love[END_REF]. We thus posit: H5: For luxury brands, brand equity positively influences brand love.

Much research on branding attests to the driving role of self-enhancement and selfdefinition in consumers' affinities to brands and, in particular, to brand identification [START_REF] Escalas | You are what they eat: The influence of reference groups on consumers' connections to brands[END_REF][START_REF] Stokburger-Sauer | Drivers of consumer-brand identification[END_REF]. Consumer-brand identification represents the consumer's psychological state of perceiving, feeling, and valuing their belongingness with a brand [START_REF] Stokburger-Sauer | Drivers of consumer-brand identification[END_REF]. By categorizing the brand as part of their self, a consumer develops a sense of oneness with the brand, establishing cognitive and emotional links that connect the brand with the self [START_REF] Park | Brand attachment and brand attitude strength: Conceptual and empirical differentiation of two critical brand equity drivers[END_REF]. Research dedicated to the extended self in the domain of consumer behavior shows that the role of products is crucial in this identification process because the incorporation of products into a person's sense of self reflects positively on the owner [START_REF] Belk | Possessions and the extended self[END_REF][START_REF] Kleine | Mundane consumption and the self: A social-identity perspective[END_REF]. Furthermore, as consumer brand identification is linked to a preference for the identified-with company's products [START_REF] Bhattacharya | Consumer-company identification: A framework for understanding consumers' relationships with companies[END_REF], we posit: H6: For luxury brands, product design value perception positively influences brand identification.

Product design may also generate feelings of love [START_REF] Albert | When consumers love their brands: Exploring the concept and its dimensions[END_REF] and reinforce self-brand connection, since a loved object expresses the consumer's deeply held values and is central to the consumer's identification with the brand [START_REF] Carroll | Some antecedents and outcomes of brand love[END_REF]. Consumers choose products not only for their functional values but also for their symbolic ones. Deep meanings conveyed by a particular brand help consumers build and strengthen their self-identity [START_REF] Escalas | Self-construal, reference groups, and brand meaning[END_REF]. As such, a consumer who identifies with a brand develops positive feelings toward it. As love for a brand should develop if the brand plays an important role in a consumer's identity construction (Albert & Merunka, 2013;[START_REF] Albert | Brand passion: Antecedents and consequences[END_REF], we posit: H7: For luxury brands, brand identification positively influences brand love.

The moderating role of design acumen

The consumer-brand relationship is also influenced by individual consumers' attitudes toward design. To better understand the influence of PDVP on the consumer-luxury brand relationship, this study heeds the call to consider consumers' individual differences as a potential moderator in the product-brand interaction [START_REF] Landwehr | The tipping point of design: How product design and brands interact to affect consumers' preferences[END_REF]. In particular, the literature underlines the importance of design acumen that reflects an ability to recognize, categorize, and evaluate product designs, and thus influence consumers' design taste [START_REF] Bloch | Seeking the Ideal Form: Product Design and Consumer Response[END_REF][START_REF] Bloch | Individual differences in the centrality of visual product aesthetics: Concept and measurement[END_REF]. Some scholars argue that people who possess this innate talent are able to make sensory connections faster and exhibit more sophisticated preferences about object design [START_REF] Csikszentmihalyi | The art of seeing: An interpretation of the aesthetic encounter: Getty Publications[END_REF]. Design acumen is expected to vary throughout the population because different consumers have varying capabilities when it comes to processing aesthetic information [START_REF] Bloch | Individual differences in the centrality of visual product aesthetics: Concept and measurement[END_REF]. Consumers who have higher design acumen are able to discern greater value in products imbued with higher design value than consumers who have lower design acumen [START_REF] Bloch | Individual differences in the centrality of visual product aesthetics: Concept and measurement[END_REF]. Consumers with high design acumen tend to perceive aspects of the self-expressive value of product design more than consumers with low design acumen [START_REF] Kumar | Beyond form and function: Why do consumers value product design[END_REF], thus reinforcing brand identification. We thus posit: H8: For luxury brands, design acumen positively moderates the relationship between product design value perception and brand identification.

Finally, as product design positively influences WTPP, consumers tend to attribute higher prices to products that they find to be more aesthetically appealing [START_REF] Bloch | Individual differences in the centrality of visual product aesthetics: Concept and measurement[END_REF][START_REF] Hoegg | The good, the bad, and the ugly: Influence of aesthetics on product feature judgments[END_REF], and as emotional attachment increases willingness to pay a price premium (WTPP) (Albert & Merunka, 2013;[START_REF] Thomson | The ties that bind: Measuring the strength of consumers' emotional attachments to brands[END_REF], we therefore posit: H9: For luxury brands, brand love positively influences willingness to pay a price premium.

Fig. 1 summarizes the conceptual framework for the proposed antecedents and consequences of PDVP for consumer-luxury brand relationships.

Insert Figure 1 4. Methodology

Data collection

To test our hypotheses, we chose products and brands that would allow us to evaluate both social and individual drivers in addition to PDVP. To analyze whether product category exerts an influence and to increase the validity of our results, we estimated the model for two distinct product categories. We chose products from two categories that are publicly consumed [START_REF] Bearden | Reference group influence on product and brand purchase decisions[END_REF] and could be easily deciphered by the reference group: a watch and a pen. Those were most appropriate as they are non-gender-specific product categories [START_REF] Kastanakis | Between the mass and the class: Antecedents of the "bandwagon" luxury consumption behavior[END_REF] familiar to, relevant for, and owned by many consumers.

We then chose two luxury brands that belong to the accessible luxury category (De Barnier, Falcy, & Valette-Florence, 2012) and lie within the price range for both premium and high-end luxury brands [START_REF] Kapferer | Where do consumers think luxury begins? A study of perceived minimum price for 21 luxury goods in 7 countries[END_REF]. We chose a Rolex Oyster Perpetual watch, selling at €4,400, and a Mont Blanc Meisterstuck pen, selling at €375 (see Appendix A).

To assess the robustness of our model, the hypotheses were tested using data collected from two distinct samples. Testing the hypotheses took the form of an online survey, presented as a survey on the consumption of luxury brands. Participants were adults recruited from the academic survey website Prolific;3 an increasingly popular medium used by researchers to collect data [START_REF] Henderson | The Color of Support: The Effect of Sponsor-Team Visual Congruence on Sponsorship Performance[END_REF][START_REF] Winterich | Knowing What It Makes: How Product Transformation Salience Increases Recycling[END_REF]. The participants took part in an 11-minute study in exchange for a small cash incentive. As luxury consumption is global, the surveys were distributed in English with no restriction in terms of residency. The final samples comprised 276 respondents for the watch (58% female; 22% owned a Rolex watch; 71% had an annual income4 of more than €50,000; and there were 23 different nationalities) and 249 for the pen (64% male; 25% owned a Mont Blanc pen; 62% had an annual income of more than €50,000; and there were 31 different nationalities). We also checked that respondents were familiar with luxury watches (mean value = 4.47 / 7) and pens (mean value = 4.58 / 7). Details of how the samples were distributed are available in Appendix D. Moreover, in order to control for the eventual bias due to the product category, we performed an additional and complementary analysis replicating the same investigation with a Mont Blanc watch priced over €3,500.

In terms of the study's operational design, respondents were first asked questions about important drivers when buying a watch or pen. Second, following the [START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF] method, a non-branded picture of the aforementioned watch or pen was presented for them to evaluate the product design. The objective was to control for any type of halo effect that could have influenced the responses. In addition, to check whether respondents had guessed the brand, we asked them to associate the product with a particular brand. The watch was associated with Rolex by 30% of the respondents, and 23% associated the pen with Mont Blanc. Erring on the side of caution, we later performed a check with a dummy variable coded 1 for those who recognized the brand. The check showed the variable to have no impact at all on any of the latent variables in our research model. Last, a branded picture and questions linked to branding were introduced (see Appendix B). The questionnaire was pre-tested with a small sample of respondents, with some minor wording changes then being made in response to their feedback. In developing the items used in our measures, we drew on existing scales wherever possible and adapted them as necessary to fit the context of our research. All items used in the survey involved seven-point agree-disagree Likert scales. A full list of all scales and items is presented in Appendix B.

Measures, analysis, and model specification

Regarding the research's causal model, all the encompassed latent variables were measured at the first-order or second-order level in a reflective manner. Design acumen, which is a moderating continuous latent variable, was specified according to the product indicator approach with mean-centered values. In addition, we relied on a consistent PLS approach to avoid inflated loadings and to generate consistent structural path coefficients (Dijkstra & Henseler, 2015a[START_REF] Dijkstra | Consistent partial least squares path modeling[END_REF].

Based on the presentation guidelines advanced by [START_REF] Henseler | Using PLS Path Modeling in New Technology Research: Updated Guidelines[END_REF], we first used the suggested criteria for overall model fit. All assessments were also based on bootstrapping with 5,000 replications [START_REF] Chin | Bootstrap cross-validation indices for PLS path model assessment[END_REF][START_REF] Hair | Common beliefs and reality about partial least squares: Comments on Rönkkö and Evermann[END_REF][START_REF] Hair | An assessment of the use of partial least squares structural equation modeling in marketing research[END_REF] as a way to compute standard errors from the standard deviation of the bootstrap estimates.

For the overall model, in addition to the goodness of fit (GoF) value, the standardized root mean squared residual (SRMR) was provided for the PLS estimates. The respective values indicated that the model showed an acceptable fit for both product categories. 5 The SRMR indices (0.049 a / 0.038 b ) were lower than the recommended cut-off value suggested by [START_REF] Hu | Cutoff criteria for fit indexes in covariance structure analysis: Conventional criteria versus new alternatives[END_REF]. In addition, the GoF values (0.554 a / 0.652 b ) were fairly high based on the work of [START_REF] Wetzels | Using PLS Path Modeling for Assessing Hierarchical Construct Models: Guidelines and Empirical Illustration[END_REF], indicating that an important percentage of the overall variance was taken into account at the measurement and structural levels.

We also tested for common method bias by using a full collinearity approach proposed by [START_REF] Kock | Common method bias in PLS-SEM: A full collinearity assessment approach[END_REF]. A full variance inflation factor VIF threshold value of 3.3 is recommended to ensure a lack of common method bias [START_REF] Kock | Common method bias in PLS-SEM: A full collinearity assessment approach[END_REF][START_REF] Kock | Lateral collinearity and misleading results in variance-based SEM: An illustration and recommendations[END_REF]. Utilizing the Kock and Lynn (2012) full collinearity test procedure, which includes random dummy variableswith random values varying from 0 to 1-as single indicator latent variables, we achieved an average VIF value of 1.872, indicating no common method bias concerns for this study.

Finally, we systematically tested for multiple control variables, namely: gender, age, income, familiarity with luxury brands and products, brand ownerships, and respondents' culture 6 .

Due to the high number of nationalities, we grouped them in terms of four similar cultural geographical areas, even if Europe as a whole remains predominant (refer to appendix D for the breakdown). Such testing showed that none of the control variables had a significant effect on any of the latent concepts investigated in this study. More precisely, all bootstrapped confidences incorporated zero, with the minimum values of endpoints of the confidence intervals 7 for each control variables, along with the minimum p-value, being respectively 8 for gender (pmin = 0,558; CImin= [-0,034; 0,071]); age (pmin = 0,442; CImin= [-0,027; 0,081]); ownership (pmin = 0,491; CImin= [-0,037; 0,097]); familiarity (pmin = 0,877; CImin= [-0,052; 0,066]); income (pmin = 0,258; CImin= [-0,112; 0,016]); culture (pmin = 0,841; CImin= [-0,068; 0,062]).

Having established the overall quality of the proposed model, we assessed internal consistency reliability, and convergent and discriminant validity. In this study, we referred solely to Dijkstra and Henseler's ρ A measure of consistent reliability for PLS construct scores [START_REF] Dijkstra | Consistent partial least squares path modeling[END_REF]. Indicators of convergent validity and reliability were satisfied: all ρ A reliabilities were greater than 0.7, and all convergent validity were greater than 0.5 (see Appendix C). To assess discriminant validity, we used a heterotrait-monotrait criterion, which was less than 0.85. Discriminant validity was thus satisfied [START_REF] Henseler | A New Criterion for Assessing Discriminant Validity in Variance-Based Structural Equation Modeling[END_REF]. 6 Coded as dummy variables for the cultural geographical areas but Far East which has too few respondents. 7 Since the larger the confidence interval around zero, the greater the likelihood of non-significance, with high corresponding p-value. 8 Detailed results are available from the authors upon request.

Once the model was validated, we evaluated its structural parts. All R²s were fairly good, ranging from 17% to 85%, thus giving additional credence to our approach. In addition, as PLS is a predictive method, we assessed the model's predictive validity following the eightstep procedure suggested by Cepeda-Carrión, Henseler, Ringle, and Roldán ( 2016 2 shows all PLS estimates evaluated for significance using a bootstrapping approach entailing 5,000 bootstrap samples. All path coefficients proved statistically significant, with 95% confidence intervals which do not include zero. Overall, all hypotheses were validated, giving support to the encompassed model (Table 2). Finally, using the measurement invariance of the composite models (MICOM) approach recently put forward by [START_REF] Henseler | Testing measurement invariance of composites using partial least squares[END_REF], we confirm that measurement invariance was established between the two luxury brands investigated in the research, thus enabling us to focus more precisely on the structural parameter estimates and their differences between the two groups under study. The overall model was thus supported for the two product categories (watches and pens) over two distinct samples, confirming the robustness of the proposed conceptual framework.

Insert Table 2 5. Results

Antecedents of PDVP

Regarding the antecedents of PDVP, both social drivers and individual drivers positively influence PDVP across the two studies, confirming H1 (β W = 0.276; p = 0.000; β P = 0.158; p = 0.011) and H2 (β W = 0.133; p = 0.037; β P = 0.440; p = 0.000). Prior to our study, the existing literature had, to our knowledge, identified only two PDVP antecedents: the importance of the need for status [START_REF] Han | Signaling status with luxury goods: The role of brand prominence[END_REF] and self-expression [START_REF] Kumar | Beyond form and function: Why do consumers value product design[END_REF]. This study enriches the literature by offering a more integrative approach to the antecedents of PDVP. Interestingly, the results show a significant difference between the watch and the pen, with the influence of social drivers being higher for the watch, and the influence of individual drivers being higher for the pen. This could be due to the intrinsic nature of each product; despite both being publicly consumed products, watches are perhaps more frequently shown to others.

Consequences of PDVP: main and mediating effects

Regarding the consequences of PDVP on consumer-brand relationship attributes, two main results have been identified. The first result reveals that PDVP positively influences brand love when there are no mediators (i.e., no direct path from brand identification and brand equity to brand love), thus confirming H3. In particular, the influence of PDVP on brand love is slightly stronger for the pen (0.203) than for the watch (0.134), suggesting a stronger influence of individual drivers than social drivers in the creation of a strong relational bond with a brand. The second result shows that the relationship between PDVP and brand love is complex. In particular, our study reveals the existence of two fully mediated paths from PDVP to brand love by unravelling (1) the mediating role of brand equity rooted in the confirmation of both H4 (β W = 0.121; p = 0.007; β P = 0.243; p = 0.000) and H5 (β W = 0.170; p = 0.000; β P = 0.230; p = 0.000); (2) the mediating role of brand identification linked to the confirmation of both H6 (β W = 0.311; p = 0.000; β P = 0.263; p = 0.000) and H7 (β W = 0.791; p = 0.000; β P = 0.826; p = 0.000); and (3) the disappearance of a direct path from PDVP to brand love in that case (β W = 0.007; p = 0.799; β P = 0.032; p = 0.291).

For a precise assessment of these mediating effects, we systematically tested a model without the indirect paths and one with both direct and indirect paths leading to brand love.

The results presented at the bottom of Table 2 were assessed by means of bootstrapped estimates with 5,000 replications. They show that indirect (β W = 0.267; p = 0.000; β P = 0.273; p = 0.000) and total effects (β W = 0.274; p = 0.000; β P = 0.305; p = 0.000) are all statically significant, whereas the direct path from PDVP to brand love is not, hence validating a full mediation mechanism between PDVP and brand love through either brand identification or brand equity.

Interestingly, it appears that for the watch as well as for the pen, the nomological network investigated reinforces the overall impact of PDVP on brand love. This result stresses the amplifier role of brand equity and brand identification as regards the impact of PDVP on brand love.

As stated above and in order to control for the eventual bias due to the product category, we tested the same research model with respect to a Mont Blanc watch, thanks to an additional survey involving 150 respondents. The PLS model achieved the same overall quality in terms of fit indices and measurement validities. In addition, 10 all the path coefficient estimates-which were statistically significant and similar in magnitude to those obtained for the Rolex watch-confirmed the same set of hypotheses, thus giving additional credence and support to our finding that product category doesn't have any significant bearing on the results.

The moderating role of design acumen

Design acumen has a positive moderating effect 11 on the relationship between PDVP and brand identification (β W = 0.618; p = 0.000; β P = 0.593; p = 0.000), thus confirming H8.

Whereas the previous literature dedicated to design acumen only explored this concept as a way of understanding variation in PDVP [START_REF] Bloch | Individual differences in the centrality of visual product aesthetics: Concept and measurement[END_REF][START_REF] Kumar | Beyond form and function: Why do consumers value product design[END_REF], our study goes further by showing how design acumen can help to strengthen a self-brand connection.

Finally, our study shows that luxury brand love has a positive direct effect on WTPP (β W = 0.683; p = 0.000; β P = 0.731; p = 0.000), thus confirming H9.

Discussion

At a theoretical level, this study heeds the call for a better understanding of the mechanisms through which product-level perception influences brand-level relationships [START_REF] Keller | Brands and branding: Research findings and future priorities[END_REF], particularly in terms of how PDVP influences consumer-luxury brand relationships.

Based on value theory, an integrated framework of the PDVP antecedents and consequences for consumer-luxury brand relationships was thus developed. This research first shows the influence of social and individual drivers on PDVP. Second, it reveals the mechanisms through which product-level value perception of design influences brand-level 11 All moderating effects have been tested by means of the product approach and centered measurement variables.

relationships for luxury brands. It explains how PDVP enhances luxury brand love through the mediating roles of brand equity and brand identification, and the moderating role of design acumen. It explores not only the direct influence of PDVP on luxury brand love but, more importantly, the full mediation roles of brand identification and brand equity, both of which act as catalysts for brand love. Finally, it reveals that luxury brand love leads to greater WTPP.

This approach allows for theory development, with the research contributing to and extending the existing literature on branding, design, and luxury in three distinct ways.

Ultimately, to the best of our knowledge, this research is one of the first including and assessing the links between product design perception, brand love and the mediating role of both brand equity and brand identification.

Theoretical implications

First, this study delves deeper into what product design brings to luxury brands. While product design is the essence of luxury brands [START_REF] Kapferer | The New Strategic Brand Management: Creating and Sustaining Brand Equity[END_REF], research has so far mainly focused on the antecedents or on the consequences of PDVP on non-luxury products (Table 1). Moreover, studies focusing on luxury products have predominantly explored the functional and aesthetic dimensions of product design [START_REF] Han | Signaling status with luxury goods: The role of brand prominence[END_REF][START_REF] Liu | The Effects of Products' Aesthetic Design on Demand and Marketing-Mix Effectiveness: The Role of Segment Prototypicality and Brand Consistency[END_REF], underlining that through tangible attributes, product design conveys intangible and symbolic attributes, such as cultural heritage [START_REF] Dion | Retail luxury strategy: assembling charisma through art and magic[END_REF]. In adopting a holistic vision of product design, our study contributes by integrating the symbolic dimension of product design with the functional and aesthetic dimensions [START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF]. In doing so, it offers a more nuanced explanation of how and why social and individual drivers affect luxury PDVP. It confirms that PDVP, through its symbolic dimension and intrinsic meanings, delivers a message about consumers' social status and self-identity.

Second, this study contributes to deepening the literature on product design value perception and luxury by offering a better understanding of the antecedents of PDVP.

Existing literature on branding and luxury has thus far identified: (1) the influence of social drivers and reference groups on product and brand purchasing decisions [START_REF] Bearden | Reference group influence on product and brand purchase decisions[END_REF]; and (2) the influence of individual drivers on luxury goods consumption [START_REF] Vigneron | A review and a conceptual framework of prestigeseeking consumer behavior[END_REF]). Yet a comprehensive viewpoint was lacking. In parallel, the antecedents of PDVP have thus far been understudied in the field of luxury products [START_REF] Han | Signaling status with luxury goods: The role of brand prominence[END_REF][START_REF] Kumar | Beyond form and function: Why do consumers value product design[END_REF].

Based on value theory, with a specific focus on luxury literature [START_REF] Groth | The exclusive value principle: the basis for prestige racing[END_REF][START_REF] Vigneron | Measuring perceptions of brand luxury[END_REF][START_REF] Wiedmann | Measuring consumers' luxury value perception: a cross-cultural framework[END_REF], this study is consistent with the buying motivation for luxury products, which are sought for their signaling value [START_REF] Grossman | Foreign counterfeiting of status goods[END_REF]. However, it goes further by offering a finer-grained understanding of the dual influence of social and individual drivers on product value. It contributes to the literature by merging the two drivers (emerging from two streams of research) into a single study in which an overarching view of PDVP antecedents for luxury products is provided.

In doing so, the study also contributes to disentangling the respective influences of social and individual drivers on PDVP. This research shows that the influence of social and individual drivers on luxury brand value, defined as the interaction between the object and the individual, varies according to the degree to which the product is made public. The role of social drivers in luxury PDVP is thus, a priori, likely to be more significant for publicly consumed products such as watches than for those that are more used in individual settings, such as pens [START_REF] Bearden | Reference group influence on product and brand purchase decisions[END_REF]. For products that are often used in a public sphere, such as watches, social drivers have a stronger influence on PDVP. A possible explanation for this lies in the value of a product in this category being rooted in the socially desirable image of the consumer who values personal achievement. As product design encompasses a symbolic dimension in addition to the functional and aesthetic dimensions, a product used publicly serves as a symbolic marker and a signal of belonging to a certain social group [START_REF] Belk | Possessions and the extended self[END_REF][START_REF] Han | Signaling status with luxury goods: The role of brand prominence[END_REF]. Conversely, for products that are less often used in a public sphere, such as pens, this research suggests individual drivers are more influential on PDVP.

Interestingly, this study also reveals that the direct link between PDVP and brand love is stronger for pens than for watches. That could be explained by the product design reflecting the consumer's inner values, aesthetic sense, and personal taste. In this case, consumers buy products for their intrinsic value. An explanation of these findings may also be found in [START_REF] Berger | Subtle signals of inconspicuous consumption[END_REF]. While some statuses are communicated through visible product design codes, others are communicated through subtle signals that appear to be a stronger means for fueling the feeling of brand love.

Third, this research enriches the literature on the consumer-brand relationship by showing how and why PDVP can enrich such a relationship in the luxury sector. In the existing literature, [START_REF] Homburg | New Product Design: Concept, Measurement, and Consequences[END_REF] identified a link between product design and brand-level attitude limited to a single item ("I would tell other people about that product"), and Kumar et al. (2015) revealed the influence of PDVP limited to a two-item brand affection scale. While these studies opened new areas for research, understanding of the complex relationship between product design and branding remains limited. Furthermore, no antecedents to this relationship were suggested, and the fragmentary definition of design given by Kumar et al. (2015) did not integrate the symbolic dimension. By using value theory, building on the holistic definition of product design that integrates its symbolic dimension, and referring to the literature on consumer-brand relationships, our research develops an overarching model that reveals the complexity of the link between PDVP and luxury brand love through the existence of two fully mediated paths.

Moreover, while the literature to date has identified the direct influence of product design on brand impression, brand image, and brand affection, this research goes further, revealing the indirect link between PDVP and luxury brand love. In line with branding literature that suggests the consumer-brand relationship is a complex phenomenon [START_REF] Fournier | Consumers and their brands: Developing relationship theory in consumer research[END_REF], this research deepens our understanding of the mechanisms involved in this relationship. It reveals the two full mediation paths-brand identification or brand equity-through which PDVP influences luxury brand love. It shows that PDVP is significantly linked to brand identification and brand equity, both of which are linked to luxury brand love. These results also underline the importance of the link between PDVP and luxury brand identification, with brand identification being more strongly correlated to brand love than brand equity. This suggests that higher PDVP results in a stronger feeling of belongingness and closeness to a brand and stronger brand love, with brand identification acting as a way to strengthen brand equity.

Finally, this research confirms the starting point of the current study-still scarcely discussed in the literature-that brand love is important because it acts as a major factor in the construction of the consumer-luxury brand relationship. In this perspective, our research extends the work of [START_REF] Nguyen | Antecedents and financial impacts of building brand love[END_REF] by revealing that not only R&D and advertising intensity are antecedents of brand love. In the case of luxury brands characterized by hedonism, product design, that triggers sensory and affective experience as well as functional and symbolic value, is also to be considered as an antecedent of brand love.

Managerial implications

At a time when luxury brands are increasingly using design to distinguish themselves and add value to their offerings, the existing literature fails to explain how and why PDVP positively influences the consumer-luxury brand relationship and, in particular, brand love.

This study confirms the importance of luxury brands strengthening their branding through product design and helps marketing managers to better capitalize on PDVP to increase brand love and to make their marketing strategies more efficient.

By highlighting the influence of social and individual drivers on PDVP, this study suggests that managers should identify the drivers that have the most impact on PDVP. As doing so, it can aid in the development of marketing activities-in particular, communications-that focus on those specific drivers. For example, managers should identify the degree to which their product is publicly consumed and adapt their communications accordingly. For publicly consumed luxury goods, managers should foster PDVP through communities of influencers to trigger word of mouth, and increase feelings of group ownership, brand identification, and brand equity, thus strengthening brand love. For luxury goods consumed in a more private setting, they should focus on intrinsic properties of product design, echoing consumers' inner values to strengthen brand equity and brand identification, and thus trigger brand love. This could be done through the creation of "connoisseur clubs". It could also be deployed in-store through the merchandising of products and seller speech. The focus on the individual drivers to increase PDVP and brand love could also be useful for managers willing to target millennials, who will fuel future growth of the luxury sector.

According to a recent Deloitte survey, 12 millennials are less interested than previous generations in outward displays of status; they buy luxury to please themselves, not to impress others. Enlarging their individual sense of self through self-expansion is thus key for managers to strengthen the brand identification of millennials [START_REF] De Kerviler | Luxury brand experiences and relationship quality for Millennials: The role of self-expansion[END_REF].

Moreover, this study may also help managers in product design innovation. This study shows that the symbolic dimension of product design has to be considered in addition to the functional and aesthetic dimensions; as such, marketing managers should deepen their understanding of the meanings conveyed by any new product through tests or semiotic analysis as part of the innovation process. To enhance symbolic and economic brand value, managers may also propose innovation of meanings, thus creating a new language for the industry [START_REF] Verganti | Design, Meanings, and Radical Innovation: A Metamodel and a Research Agenda[END_REF]. Building on emergent sociocultural trends [START_REF] Dell'era | Strategies of Innovation and Imitation of Product Languages[END_REF], such as a new product design process, could increase interest from consumers and their reference groups, thus enhancing PDVP, as well as strengthening brand identification and equity. This would consequently increase brand love and WTPP.

Finally, this study shows why and how managers can use PDVP to trigger brand love, which ultimately allows them to set higher prices and generate additional revenue thanks to consumers' increased WTPP.

Limitations and perspective

This study has some limitations that provide worthwhile avenues for future research. First, it is still exploratory due to the small sample size. While this study focuses on accessible luxury categories such as watches and pens, investigating the validity of this study's model when applied to other luxury product categories, such as cars, as well as comparisons to ultraluxury products and non-luxury products, would be an interesting avenue for future research.

In addition, even though the culture doesn't have any impact on our results, the majority of respondents were from Europe. Replicating our approach in other cultural settings, such as Far East countries or North and South America could provide more contrasted results.

Second, this study focuses on two iconic products that are part of brands with rich heritages [START_REF] Pecot | Cognitive outcomes of brand heritage: A signaling perspective[END_REF]. Considering the case of new or unknown brands would provide worthwhile avenues for future research.

Third, while the study shows a difference between publicly consumed products and those used in private settings, the role of (in)conspicuous consumption may also be considered [START_REF] Berger | Subtle signals of inconspicuous consumption[END_REF] to check whether PDVP is higher for the consumption of luxury brands that users prefer to keep discrete. 13 Fourth, this study reveals that product design is an antecedent of brand love. Further research could go further by studying the extent to which design investments help firms building brand love and affect brand financial impacts on top of R&D and advertising expenditures [START_REF] Nguyen | Antecedents and financial impacts of building brand love[END_REF].

Finally, the last area for further exploration derives from the fact that this article focuses on identifying how PDVP relates to consumer-luxury brand relationships. While this study unveils the complexity of the link between PDVP and the consumer-brand relationship, further research could determine the extent to which each PDVP dimension (functional, aesthetic, and symbolic) influences consumer-luxury brand relationship outcomes such as brand equity, brand identification, and brand love. 13 We thank the reviewer for raising these points.

  ): (1) create a training sample (randomly drawing two thirds of the observations); (2) estimate model parameters on the training sample; (3) standardize the holdout sample data; (4) create construct scores for the holdout sample as linear combinations of the respective indicators using the weights obtained from the training sample; (5) standardize the construct scores for the holdout sample; (6) create prediction scores for each endogenous construct in the holdout sample using the path coefficients obtained from the training sample; (7) calculate for each endogenous construct of the holdout sample the proportion of explained variance (R²) as the squared correlation of the prediction scores and the construct scores; and (8) contrast the R² values of the holdout sample with the R² values obtained from the training sample. The results indicate similar R-square 9 values for the training sample and the holdout sample, thus providing additional support to our findings. Table

Figure 1 .

 1 Figure 1. Conceptual Framework

The authors thank the Editors, the Guest Editor Pr. Géraldine Michel, and the anonymous reviewers for their comments and helpful advice.

Throughout the article, the expressions "symbolic" and "symbolism" are used interchangeably.

www.prolific.co

According to a recent survey in France(INSEE, 2020), the wealth threshold is estimated at twice the median income, i.e., €50,000. In addition, it corresponds to the threshold mentioned by[START_REF] Kapferer | Which consumers believe luxury must be expensive and why? A cross-cultural comparison of motivations[END_REF].

Watch: subscript a; pen: subscript b.

Detailed results are not given here in order to save space, but are fully available upon request.

Detailed results are not given here in order to save space, but are fully available upon request.

https://www2.deloitte.com/ch/en/pages/consumer-industrial-products/articles/young-premium-consumer.html

Park&Lessig, 1977 (adaptation) A1 I would seek information about the product listed below from an association of professionals or independent group of experts. A2 I would seek information from professionals who work with the product. A3 I would seek product related knowledge and experience (such as how product A's performance compares to product B's) from those friends, neighbors, relatives, or work associates who have reliable information about the products. A4 The product I select is influenced by observing a seal of approval of an independent testing agency. Utilitarian influence B1 To satisfy the expectations of fellow work associates, my decision to purchase a particular product is influenced by their preferences. B2 My decision to purchase a particular product is influenced by the preferences of people with whom I have social interaction. B3 My decision to purchase a particular product is influenced by the preferences of family members. B4 The desire to satisfy the expectations others have of me has an impact on my product choice. Value-expressive influence C1 I feel that the purchase or use of a particular product will enhance the image others have of me. C2 I feel that those who purchase or use a particular product possess the characteristics which I would like to have. C3 I feel that it would be nice to be like the type of person who advertisements show using a particular product (Brad Pitt wearing Tag Heuer watch). C4 I feel that the people who purchase a particular product are admired or respected by others. C5 I feel that the purchase of a particular product helps me show others whatI am, or would like to be (such as an athlete or a successful businessperson).

INDIVIDUAL DRIVER

Wolter et al., 2016 Self-consistency (similarity) Product X is consistent with how I see myself. Product X is a mirror image of me. Self-enhancement (prestige) People who I care about think that product X is a well-respected product. People who I care about think highly of product X. People who I care about think that product X has a good reputation. Self-differentiation (distinctiveness) No other watch/pen/... is the same as product X. Product X stands out from its competitors. Compared to other watches/cars, product X is original.

PRODUCT DESIGN VALUE PERCEPTION Homburg et al., 2015 Aesthetic

The product is visually striking. The product is good looking. The product looks appealing.

Functional

The product is likely to perform well/seems to be capable of doing its job. The product seems to be functional.

Symbolic

The product would help me in establishing a distinctive image. The product would be helpful to distinguish myself from the mass. The product would accurately symbolize or express my achievements. DESIGN ACUMEN Bloch, 2003 Being able to see subtle differences in product designs is one skill that I have developed over time. I see things in a product's design that other people tend to pass over. I have the ability to imagine how a product will fit in with designs of other things I already own. I have a pretty good idea of what makes one product look better than its competitors. BRAND LOVE [START_REF] Bagozzi | Brand love: development and validation of a practical scale[END_REF] To what extent do you feel that wearing brand X says something "true" and "deep" about you as a person? To what extent do you feel yourself desiring to own brand X ? Please express the extent to which you feel emotionally connected to the brand X? Please express the extent to which you believe that you will be owning the brand X for a long time. Suppose brand XXX were to go out of existence, to what extent would you feel anxiety. BRAND EQUITY [START_REF] Yoo | An examination of selected marketing mix elements and brand equity[END_REF] It makes sense to buy X instead of any other brand, even if they are the same. Even if another brand has the same features as X, I would prefer to buy X. If there is another brand as good as X, I prefer to buy X. If another brand is not different from X in any way, it seems smarter to purchase X.

CONSUMER BRAND IDENTIFICATION

Stokburger-Sauer et al., 2012 I feel a strong sense of belonging to brand X. I identify strongly with brand X. Brand X embodies what I believe in. Brand X is like a part of me. Brand X has a great deal of personal meaning for me. WILLINGNESS TO PAY A PRICE PREMIUM Netemeyer et al., 2004 The price of (brand name) would have to go up quite a bit before I would switch to another brand of (product). I am willing to pay a higher price for (brand name) brand of (product) than for other brands of (product). I am willing to pay ___% more for (brand name) brand over other brands of (product): 0% 5% 10% 15% 20% 25% 30%, or more. I am willing to pay a lot more for (brand name) than other brands of (product category). Note: With the exception of Item 3 of Willingness to Pay a Price Premium, all items are measured on sevenpoint strongly disagree to strongly agree scales.

Appendix C. Reliability and convergent validity indices