Celebrity Endorsement and the Attitude Towards Luxury Brands for Sustainable Consumption

Abstract

Taking into consideration the increasing role of sustainability in the luxury industry, our study investigates the role of celebrity credibility, celebrity familiarity, luxury brand value, and brand sustainability awareness on attitude towards celebrity, brand, and purchase intention for sustainable consumption. For this, we explored relationships among these variables to test a conceptual model which is developed using existing knowledge available in academic research on this topic. Data for testing were collected from high-end retail stores in the UK about the world top luxury brands by brand value in 2019, also acknowledged for their major engagement in sustainability. Findings from a survey of 514 consumers suggest that celebrity credibility is a very strong key to increasing purchase intentions of sustainable luxury goods. The study has important implications for the expansion of current literature, theory development and business practices. Limitations of the study are also outlined, and directions for future research are considered too.

1. Introduction

Outstanding between exclusivity [1] and inspiration [2], luxury represents an ambiguous concept, used by customers to construct a desirable self-concept by communicating central beliefs, attitudes and values to others (self-expressive) or alternatively, to gain approval in social situations (social-adjustive) [3,4]. Nevertheless, thanks to the process of democratisation of luxury [5] and the trickle-down effect from luxury to mainstream [6], currently the offering of the sector is increasingly related to the value system, such as social and environmental responsibility. Accordingly, nowadays the concept of luxury is no more strictly related to the economic value of the offering, or to the individual’s spending capacity, while it is always more frequently relative to a lifestyle connected to emotional and experiential values and to a more intrinsically ethical/social idea of value. As a result, the landmark of sustainable luxury refers to the commitment of luxury companies, responsible for their production to both society and the environment. Thus, due to the growing consumer concern, all the greatest luxury firms are not able to leave sustainability out of consideration anymore [7]. Indeed, many luxury brands as Gucci, Saint Laurent, Prada and Chanel engaged responsible behaviours, by promoting the use of energy efficient light sources, or adopting recycling practices in the product supply chain, or are committed to going fur-free. They pursue to focus on rarity, excellent quality and artisanship, while incorporating sustainability goals [8]. Despite this, firms’ sustainable behaviours, although necessary, seems not to orientate luxury consumption directly. Sure enough, consumers promptly disapprove luxury companies adopting practices in contrast with the environment protection, while being indifferent to communication underlining their sustainable activities. In other words, consumers expect luxury brands to be respectful toward the environment and society as an intrinsic and authentic dimension of their mandate and of their value [9]. In other words, sustainability is not considered as an additional attribute to the pre-existing luxury product offering, instrumental to its reinforcement, but it generates an exclusive property that leads to the definition of new business models, for instance starting from the existing natural and rare resources and from their connection with the territorial realities [9], i.e., social sustainability. Companies have different motives for engaging in sustainable practices, such as managing upside benefits and downside risks, and value creation, by avoiding the negative effects of noncompliance. Customers, instead, by according their preference to these enterprises, express their “personal formula” of sustainable consumption, without turning down their aspiration for luxury and their responsibility towards the world.

In this deeply increasing niche, the firms’ effort consists in communicating about luxury’s true values to customers—rarity, exclusivity, artisanship and respect towards society and environment—without betraying the allure luxury mandate. Therefore, promotional activities of luxury firms’ toward sustainability, as a non-evaluative meaning transfer, are limited and responsible communication represents a spreading challenge for the sector, that require directed marketing strategies, different from commercial. Celebrity endorsement, based on celebrity attractiveness and expertise toward sustainability, may produce a positive impact on consumers’ brand awareness also in the luxury sector, increasing the brand value, leading to improved business performance and creating brand equity [10]. Notwithstanding, it represents a not well-investigated strand of research a there are few empirical studies on what factors should be considered in utilising endorsers in marketing sustainable products [11], especially in the luxury industry.

Hence, the aim of the paper consists in exploring the role of celebrity endorsement, in terms of credibility, familiarity, luxury brand value, and brand sustainability awareness on attitude towards celebrity, brand and purchase intentions to stimulate a sustainable consumption.

Celebrity endorser is defined as an individual who enjoys public recognition and uses this recognition on behalf of the consumers’ goods, by appearing with them in the advertisement [12,13]. Celebrities are widely used to promote a wide range of goods and services [14]. They exert powerful influence across all facets of popular culture and public life and hold certain meanings in the eyes of the consumers, which marketers use in order to persuade them [15,16].

Celebrity endorsers are in use, since the late 19th century, with one early example dates back at 1896. The use of celebrity endorsers in advertisements in the last few decades has increased rapidly. In 1975, 15% of television advertising featured celebrities, in 1978, it went up to 20%, while in recent years, it is estimated that one of the four advertisements in UK and US use celebrity endorsers [17,18,19]. While, 60 to 70% of celebrities are used in countries like India, Japan, and other Far East countries [19]. Of the billions of dollars allocated annually for television advertising, approximately 10% is served on endorsers [14]. Music star Rihanna earned $220 millions from her endorsements in 2016, American Express and CoverGirl spent $75 million on advertisements featuring Ellen DeGeneres, Nike spent $1.44 billion on celebrity endorsement, while, Gillette signed an endorsement deal with soccer player David Beckham costing $50 million. It is suggested that in return, celebrities bring a positive impact on a firm’s stock prices. On average, celebrity endorsers increase the stock returns up to 0.44%, only on the day of the announcement [20,21].

The importance of celebrity endorsements has made several researchers examine its effectiveness [22]. It is suggested that celebrity endorsers cut off the clutter in conveying the brand message to the consumers. They enhance product desirability and product glamour [15]. They are an effective strategy for gaining attention [23], improving marketing effectiveness [24], creating positive emotions towards the product/brand [25], impacting brand attitude, influencing on brand recall/recognition [26], enhancing purchases [27], impacting on loyalty [28], and improving product sales [29]. Recent research shows that celebrity credibility enhances brand image [30], brand credibility [31], brand equity [32], corporate credibility, and corporate image [33]. Despite these studies, current research shows that very little research work has been done on celebrity credibility [34], luxury brand value, brand awareness, and familiarity, and further their effects on attitudinal and behavioural constructs. To minimise these gaps, a conceptual model based on these relationships is developed. To address these relationships, associative network theory and theory of planned behaviour are used. Then, by verifying the conceptual model, the purpose of the study is to examine the importance of celebrity credibility, luxury brand value, brand awareness, and familiarity on attitudinal and behavioural constructs of the consumers in order to use celebrity endorsers to enhance sustainable product allure and glamour also in the luxury sector, considering that the domain of luxury is disconnected from daily purchases. Results from this study would help managers and advertisers to understand these effects in detail.

The paper starts with an explanation of the conceptual model, and a series of hypotheses are presented. Next, the paper sets out the research method, and a large-scale field survey investigation is undertaken to examine the results of the research hypotheses. Finally, the discussion and conclusions are presented.

2. Conceptual Framework

The conceptual model applied in this study is based on two theories. The first theory is of associative network theory, while the second theory is of planned behaviour. Associative network theory is used to explain the relationship between the celebrity and the brand. Theory of planned behaviour is used to explain the relationship between attitude, social norms, and behavioural control.

According to the associative network theory, human memory is defined as a network of interconnected nodes. Each node holds information and is connected or associated with other node based on associative links, such that when an individual thinks of something, s/he also activates other associated nodes [24]. In this study celebrity and brand represent nodes, which are interlinked and associated to each other, such that when consumers think of a celebrity, they may actually think of the endorsed brand, and vice versa [24]. This linking could provide a desirable association conducive to the creation of brand awareness and brand value [32].

The theory of planned behaviour—developed by Ajzen [35,36]—corrects the original model’s limitation in predicting behaviour over which people have only partial discretionary control [37]. According to this theory, the most immediate and important predictor of behaviour is the person’s intention [37,38]. The intention is determined by the attitude, i.e., the person’s overall evaluation of favourableness or unfavourableness of the outcomes of the behavioural performance [36,37]. The second construct is a subjective norm, i.e., the person’s perception of social pressure to perform or not to perform the behaviour. The last is perceived behavioural control, which suggests that the individual’s perceptions of the ease or difficulty of performing the behaviour of the interest [37,38]. In this study, all the three, i.e., attitudes (attitude towards the celebrity, attitude towards the brand), social norm (luxury brand value), and behavioural control (purchase intentions), has been taken to the model.

Hence, Figure 1 presents the conceptual model applied in this study.

2.1. Celebrity Credibility and Celebrity Endorsement

Employing an appropriate celebrity endorser to promote a brand is an important, but yet difficult task [16,39]. Firms use several celebrity attributes to reduce the level of risk, involved in hiring a celebrity, such as an image, familiarity, and match-up between the brand and celebrity, etc., and one of the most important in all of them is celebrity credibility [39]. Celebrity credibility is defined as the extent to which the recipient perceives the source as having relevant knowledge and/or experience, and therefore, trusts the source to give unbiased information [15,34].

Research on the celebrity endorsement topic is derived from a landmark study on source credibility carried out by Hovland and his associates in 1953 [40]. Their study fundamentally rests on two general models: The source attractiveness model and the source credibility model. The source credibility model encompassed the expertness and trustworthiness of the source, while the source attractiveness model encompassed the attractiveness of the source. Source expertness is defined as the extent to which the source is perceived to be a source of valid assertions; source attractiveness is defined as the degree to which the source is considered to be familiar, likeable, similar and attractive; and source trustworthiness is defined as the degree of confidence in the communicator’s intent to communicate the assertions he/she considers most valid [41,42,43]. Therefore, a celebrity engaged in sustainable causes can influence luxury consumers thanks to his attractiveness, justified by means of the source’s expertness and trustworthiness.

A number of empirical investigations have been carried out into the effectiveness of celebrity credibility [19,41,43,44,45,46,47]. Most researchers have supported the generalisation that celebrity credibility influences beliefs, opinions, attitudes, behaviours and other credibility constructs [43,48,49,50]. Miller and Basehart [51] and McGinnies and Ward [52] investigated the impact of celebrity credibility on the persuasibility of the communication. Their results showed that when the celebrity endorser was highly credible, there was a positive impact on message persuasiveness and attitude change, while a celebrity endorser with low credibility was considered to be a questionable message source [19,34,52,53].

Further, it has been observed that a credible celebrity can also help in inducing the desired behaviour with regards to the advertisement, brand and purchase intention [49,54,55,56]. Lafferty and Goldsmith [48], Goldsmith et al. [49] and Lafferty et al. [44] demonstrated the significant effects of celebrity credibility on attitude towards advertisement, attitude towards brand and purchase intention. La Ferle and Choi [50] examined a similar model in the South Korean context and proved that the celebrity credibility model had a positive effect. Sallam and Wahid [54] conducted a similar study within the context of Yemen and found a higher impact of celebrity credibility on all three attitudinal and behavioural constructs. Despite these studies, there is little evidence of celebrity credibility on attitude towards celebrity.

Based on this, the next hypothesis is:

Hypothesis 1.

Celebrity credibility has a positive attitude towards celebrity endorsement.

2.2. Celebrity Familiariry and Celebrity Endorsement

Familiarity is defined as an individual’s familiarity with the source through any media exposure [57]. According to Fleck et al. [58], the effectiveness and acceptance of the message delivery may depend on the individual’s familiarity with the source. It means that when the individual is familiar with the source, then the individual will less look for external information, while, the unfamiliarity with the source can increase the need for the external information [59].

Familiarity within the context of celebrity endorsement suggests consumers’ knowledge regarding the celebrity and show how much they are familiar to the celebrity [60,61,62]. Previous research by using the relevant construct, i.e., brand, has proved that when the consumers are familiar with the brand, they will show a positive attitude and confidence towards the brand. While, when the consumers are unfamiliar with the source, they show a less positive effect and confidence towards the brand [59,63,64]. When consumers are unfamiliar to the celebrity, they are less likely to process the information in a similar way, mostly due to the reason that they have to learn and form accurate information. In the case of familiar celebrities, consumers already have some prior knowledge. In such circumstances, they are more likely to engage in a relatively less extensive, more confirmation-based processing and show higher positive attitudes toward the celebrity [64]. Hence, based on this argument, it can be suggested that celebrity familiarity has a positive effect on attitude towards the celebrity endorsement. Based on this, the next hypothesis is:

Hypothesis 2.

Celebrity familiarity has a positive effect on attitude towards the celebrity endorsement.

2.3. Attitude towards Celebrity Endorsement and Purchase Intention

Attitude is defined as an individual’s personal evaluation, emotional feelings, and actions tendency towards affairs, objects, ideas, and behaviours [19]. It acts as a basis to individual’s willingness in behaving under a specific manner [65,66]. The concept of attitude has been vastly applied in the marketing context since the 1960s [66]. Gresham and Shrimp [67] firstly proposed the impact of attitude on behaviour in marketing. It is suggested that a highly likeable and credible celebrity can form constructive consumers’ attitude, which can further affect the behavioural intention [44,67,68]. It is also confirmed from the current literature that celebrity endorsement brings a significant and direct effect on the purchase intention [49,59,60,61,62,69]. Based on the above discussions, the next hypothesis suggests that:

Hypothesis 3a.

Attitude towards celebrity endorsement has a positive effect on purchase intentions.

2.4. Attitude towards Celebrity Endorsement and Brand Awareness

One of the major objectives of advertising is to create brand awareness, so that consumers can recall and recognise the brand name at the purchasing time [70]. Celebrity endorsers as an advertising source are an effective strategy to enhance brand recall and recognition [71]. They create a co-branding between themselves and the brand, such that when the consumers get information on celebrity endorsers, they equally, based on the associative nodes, get the awareness on the brand [72,73]. The associative nodes theory suggests that when a celebrity endorses a brand, consumers’ perception of the celebrity link up with the associations of the endorsed brand in the memory [31,46]. Such a connection transfers the meanings of the celebrity, sustainability, for instance, among others, to the endorsed brand and increases brand awareness [46], also in terms of responsible choices towards society and environment. Research has found that celebrity endorsers are more effective than various other types of endorsement techniques in creating brand awareness [27,30]. Despite the importance of this relationship, only a little evidence has been found on examining the effect of celebrity endorsement on brand sustainability awareness [31,32]. Therefore, the next hypothesis is:

Hypothesis 3b.

Attitude towards celebrity endorsement has a positive effect on brand sustainability awareness.

2.5. Attitude towards Celebrity Endorsement and Brand Attitude

Existing perceptions on the favourability of the credible celebrity can highly influence consumers’ processing and assessment regarding the brand [68]. Many studies have explained and examined the influence of celebrity credibility on attitude towards the brand [24,55,56,74]. Solomon [25] suggested that consumers do not know the celebrity; however, they admire and accept them as reference groups, such as athletes, celebrities, performers or successful businesspersons. According to Solomon [25], consumers match themselves with celebrities and take them as a reference. Since consumers admire the celebrity, they would change their perception to the particular brand, when they see the advertisement endorsed by the celebrity endorser. For example, if the celebrity endorser adopts a sustainable behaviour, a consumer might perceive the brand as sustainable as the celebrity is and change the perception towards the brand.

Literature [68] reveals that celebrity endorsement can have a direct and indirect effect on attitude towards the brand. Goldsmith et al. [49] suggested that the effect of celebrity credibility on attitude towards the brand was mediated through the attitude towards the advertising. On the other-hand, Sallam [68] suggested that celebrity credibility had a partial effect on attitude towards the brand, while, Wang et al. [74] found that a celebrity endorser with high credibility could create an attitude towards the brand. Therefore, the next hypothesis is:

Hypothesis 3c.

The celebrity endorsement will positively affect the Attitude towards the brand.

2.6. Attitude Celebrity Endorsement Effect and Luxury Brand Value

Radon [75] suggested that luxury brands are built on perceptions and images, and this can be strengthened by associating the brands with celebrity endorsers. Celebrity endorsers are extremely important and valuable to the brands, especially in the luxury fashion sectors [76]. They have enormous power and can successfully contribute to make and create luxury brands. They can transfer their personality, glamour, beauty, talent, style, status and sustainable behaviour to the luxury brands. Brands like Gucci, Prada, Dior, Swarovski, etc. have buoyed their demand and expand their markets by the involvement of celebrity status.

Research on celebrity endorsement effect on luxury brands is not extensive. Stafford et al. [77] and Spry et al. [32] suggested that the effectiveness of a celebrity endorsement can create credibility for a luxury brand. Okonkwo [76] suggested that celebrity endorsement is a great brand awareness creation tool, which can transfer the personality and status to the luxury brands’ image. Pai [78] found that for luxury brands, using a celebrity endorser as a spokesperson leads to better advertising effects. Mostly, these researchers have given their suggestions on the topic, and very few of them has tried to examine the effect of celebrity endorsement on luxury brand. Based on this, the next hypothesis is:

Hypothesis 3d.

Attitude towards celebrity endorsement has a significant effect on the sustainable luxury brand value.

2.7. Brand Awareness and Brand Attitude

Brand awareness refers to whether consumers can recall or recognise a brand, or simply whether or not consumers know regarding a brand [79]. Brand awareness provides a learning advantage for consumers and influences them in making a decision by including the brand in their consideration set [79]. A familiar brand has a better information retrieval in the brain and has higher chances of chosen by consumers.

Previous researchers [80] have suggested that brand awareness consists of brand recall and brand recognition. Brand recall means when consumers see a product, can they recall a brand name exactly, while brand recognition means whether consumers the ability to identify a brand, when there is a brand cue, i.e., whether consumers can tell a brand correctly, if they ever see it again [80]. Furthermore, researchers [81] also differentiated between both of the parts, above, of brand awareness, based on depth and width. Depth is defined as how consumers recall or identify brand and width means when consumers purchase a product, whether a brand comes in their mind [80].

It is suggested that brand awareness has a positive effect on the brand attitude [80]. Consumers mostly prefer to buy a familiar and well-known brand [82]. They will show positive attitudes and preferences towards the brands, which are established and highly recognisable [80,83]. However, despite this importance, research on brand awareness effects on brand attitude is very scarce [79]. Mostly, researchers [82] have used lab experiments to examine these effects, and there is limited research on examining the effects based on quantitative data. To cover this gap, the next hypothesis is:

Hypothesis 4a.

Brand awareness has a positive effect on brand attitude.

2.8. Brand Awareness and Purchase Intention

Alike, brand awareness effects on brand attitude, this study has also analysed the effects of brand awareness on purchase intention. Mostly researchers [80,84] have suggested that brand awareness can influence consumers’ purchase intention. According to the researchers [80,85], a well-known brand can highly incline consumers to purchase the brand, whereas, an unfamiliar brand can decrease consumers’ intention to make the purchase. Although, previous researchers [80,85,86] have found the positive effects of brand awareness on purchase intention, there is still a little evidence available in the literature. Therefore, the next hypothesis is:

Hypothesis 4b.

Brand awareness has a positive effect on purchase intention.

2.9. Brand Attitude on Purchase Intention

A precedent has been set in the literature for the relationship between attitude towards the advertising, attitude towards the brand, and purchase intentions [49]. These causal sequences of attitude towards advertising to attitude towards brands, and attitude towards brand leading to purchase intention is an important measure of the source (i.e., advertising, celebrity, and brand) effectiveness [49]. Brand attitude suggests consumers’ emotional reaction towards a brand [87], while, purchase intention suggests whether the individual would buy the brand. Previous researchers [44,49,87] have examined consumers’ positive attitude towards the brand on buying behaviour. According to this research [49,87], positive attitude towards the brand increases consumers chances of purchase intention. Based on this relationship, the next hypothesis is:

Hypothesis 5.

Brand attitude has a positive effect on purchase intentions.

2.10. Vanity and Luxury Brand Value

Vanity is defined as having an excessive concern, and/or a positive view of one’s physical appearance/personal achievements [73]. It is characterised by strong emphases on the outward appearance, because of its physical concerns and on conveying social status through conspicuous consumption, because of its achievement concerns [88]. In this sense, it can be claimed that vanity is a personality trait, which is influenced by social/outside pressures [89].

Netemeyer et al. [90] categorised vanity based on physical and achievement vanity. They suggested that physical vanity is a concern for, and/or a positive view of, one’s physical appearance, while, achievement vanity is an excessive concern for, and/or a positive view of, one’s personal achievements [89]. The idea of physical vanity can be observed through various mediums, where the public are introduced to a constant stream of beautiful men and women, and are suggested that if they follow certain lifestyles, they will enhance their attractiveness. Within the academic world, studies [89] have suggested that physical attractiveness is significantly associated with social popularity, power, as well as increased self-esteem. It is suggested that attractive people are conceived as dominant, healthy, clever, and sexually attractive [89,91]. Achievement vanity is explained based on material possessions, such as success or status, which explains the achievements of individuals. Once again, various mediums are used to show individuals’ off achievements, which they can achieve by following certain lifestyles.

Discourse on a vanity can be found in disciplines as diverse as linguistics, anthropology, economics, poetry and even consumer behaviour. In marketing literature, research suggests that the behaviour of vanity is usually observed by consumers to signal their social status and wealth by consuming luxury brands [92,93]. As luxury brands are appearance-related conspicuous products, vanity plays a role in influencing, motivating, and promoting brands to the consumers [88,94].

Vanity has received very little attention in the consumer behaviour or consumer affairs literature, and only a few studies have been found on examining its effects on luxury brands. Sedikides et al. [95] suggested that influential consumers, who are prone to vanity, also have higher spending on high-prestige products. Durvasula et al. [89] claimed that vanity was importantly linked with the consumption of luxury brands. Park et al. [88] failed to find the effect of vanity on luxury brands, while Hung et al. [73] only found the effect of vanity on purchase intention towards luxury brands and could not find any moderating effect of vanity on consumer perception, social influence, and purchase. Hence, the next hypothesis is:

Hypothesis 6.

Vanity has a positive effect on intentions.

2.11. Luxury Brand and Purchase Intention

The word ‘luxury’ in the luxury brand is derived from the Latin word ‘luxuria’, and it means ‘extra of life’ [96]. There is no universally recognised marketing definition of luxury brands in the literature. However, authors have usually classified them with the words like hedonistic experience, high price, heritage, controlled distribution, personalised service, social privilege, affluence, and luxury [96,97]. Luxury brands provide extra pleasure, and their usage brings supremacy, status, and esteem in its users.

Radon [75] mentioned that luxury brands have three benefits, i.e., functional benefits (intrinsic advantages of the brands), experiential benefits (feelings one get after the consumption), and symbolic benefits (extrinsic advantages of the products and services consumption). Hung et al. [73] suggested that functional benefits manifest the actual goods and service quality as perceived by the consumers. The experiential benefits consist of feelings and thoughts, which suggest that luxury brand is precious, rare and unique, while, the last category, i.e., symbolic benefits, indicate conspicuousness, expensiveness, and wealth of the brand [73]. Overall, these benefits impact the overall consumers’ motivation to consume the luxury brand.

Luxury brands are critical extrinsic cues, which help consumers to gain social status in society [98]. Luxury brands enable consumers to satisfy their socio-psychological needs and are used as a means to impress others in society [98,99]. Bian and Forsythe [100] suggested that consumers, who desire self-expression and self-presentation attitudes, seek luxury brands that possess characteristics that reflect consumers’ intrinsic values and beliefs. These attitudes further promote consumers’ purchase intentions towards luxury brands [100,101]. Based on these explanations, the next hypothesis is:

Hypothesis 7.

Luxury brand value has a positive effect on purchase intention.

3. Materials and Methodology

3.1. Empirical Setting

The study hypotheses are tested through the perceptions of consumers of high-end retail shops who enjoy a favourable reputation, due to the retailers’ brand names [102,103]. The data were collected between May 2019 and August 2019 in London from the world top luxury brands by brand value in 2019, also acknowledged for their major engagement in sustainability [104]. This research uses non-probability snowballing as a distribution method to increase the sample size and access a representative sample within an inter-connected network of people [105]. This research collects a total of 562 questionnaires through face-to-face questionnaire and online survey, but excludes 48, due to large amounts of missing data. After making every possible effort to increase the response rate, this research obtains and analyses a total of 514 usable, completed questionnaires.

The majority of participants are female (56.8%) between the ages of 40 to 49 (29.2%) and have the place to purchase a luxury product than two times (42.6%) and twice (205%) per month. A high percentage of respondents are businessman/woman (34.3%). 64.5% are professionals, such as lawyers, dentists or architects. 17.5% are retired. 66.3% of the respondents have a master’s degree or above.

Table 1. Demographic profile (N = 514).

	Frequency	Percent		Frequency	Percent
Visit the Place to Purchase a Luxury Product Per Month			Employment
Once per year	90	17.5	Businessman/woman	203	39.5
Twice	205	39.9	Lawyer, dentist or architect, etc.	64	12.5
More than two times	219	42.6	Office/clerical staffs	17	3.3
Gender			Worker	9	1.8
Female	292	56.8	Civil servant	9	1.8
Male	222	43.2	Craftsman	27	5.3
Age			Student	29	5.6
19 years old or less	27	5.3	Housewife	60	11.7
20 to 29 years	98	19.1	Retired	90	17.5
30 to 39 years	108	21.0	Unemployed	6	1.2
40 to 49 years	118	23.0	Degree
50 to 59 years	88	17.1	High school	24	4.7
60 years old or more	75	14.6	Undergraduate	149	29.0
			Postgraduate and above	341	66.3

illustrates the respondent characteristics in more detail.

3.2. Measurement

This paper used the scale measurement from earlier studies, recognised to be psychometrically sound [106,107]. Celebrity credibility is measured based on three constructs (i) attractiveness, (ii) trustworthiness, and (iii) expertise [32,108]. Familiarity is tested through three items based on Spy et al.’s [32] study. Attitude towards celebrity endorsement scale contains six items [41,109,110]. Brand awareness is measured based on Ohanian [41] and Spry et al. [32] recommendation with four items. Brand attitude is measured through brand association [111,112,113,114,115,116] and brand belief [33,117,118,119,120,121]. Vanity is also obtained from Hung et al. [73]. Luxury brand value is measured via three constructs (i) symbolic, (ii) experiential, and (iii) functional [73,122]. Purchase intention is measured through 3 based on the recommendation by Calvo Porral and Lang [123] and Hung et al. [73]. Respondents are asked to indicate on seven-point Likert-type scales ranging from strongly disagree (1), to strongly agree (7).

The research measurement items are examined for reliability and validity. The construct level reliability is examined to ensures that items allocated to the same constructs reveal a higher relationship with other items. The construct level reliabilities of the scales are well above the commonly accepted requirements for psychometric reliability tests (0.708 through 0.810 > 0.70) [107,124]. The descriptive data for the constructs of interest are illustrated in

Table 2. Measurement items.

Scale	Scale Items	Major References	Codes
Celebrity Credibility	Attractiveness
	I find the celebrity endorser for brand X attractive	Ohanian (1990); Spry et al. (2009)	CCA1
	I find the celebrity endorser for brand X classy		CCA2
	Brand X is sexy		CCA3
	Brand X is handsome/beautiful		CCA4
	I find the celebrity endorser for brand X elegant		CCA5
	Trustworthiness
	I find the celebrity endorser for brand X dependable	Ohanian (1990); Spry et al. (2009)	CCT1
	Brand X is honest		CCT2
	I find the celebrity endorser for brand X reliable		CCT3
	Brand X is sincere		CCT4
	Brand X is trustworthy		CCT5
	Expertise
	Brand X is expert	Ohanian (1990); Spry et al. (2009)	CCE1
	Brand X is experienced		CCE2
	Brand X is knowledgeable		CCE3
	Brand X is qualified		CCE4
	Brand X is skilled		CCE5
Familiarity	I find the celebrity for brand X familiar	Spry et al. (2011)	FAM1
	I can easily recognise the celebrity for brand X		FAM2
	I have heard of the celebrity for brand X before		FAM3
Attitude towards celebrity endorsement	Celebrity endorsements increase the value of their endorsed fashion brand X	Ohanian (1990)	AT1
	Celebrity endorsers’ image and value increase their endorsed fashion brand X		AT2
	Fashion brand X with celebrity endorsement is more favourable		AT3
	I think celebrity endorsement is an important factor when I make my decision about brand X		AT4
	Celebrity endorsements of brand X could gain consumers attention easily	Dyson and Turco (1998)	AT5
	Celebrity was one of the most effective methods of brand X building advertisement	Pringle (2004)	AT6
Brand awareness	I am aware of brand X product category	Ohanian (1990); Spry et al. (2009)	BW1
	I can recognise brand X product category		BW2
	Some characteristics of brand X come to mind quickly		BW3
	I remember brand X just because the celebrities are endorsing it		BW4
Brand Attitude	Brand association
	It is likely that brand X product category offers good value for money	Spry et al. (2009)	BAA1
	It is likely that brand X product category would be technically advanced		BAA2
	I like brand X product category		BAA3
	I trust brand X as a manufacturer of product category		BAA4
	I would feel proud to own a brand X	Pappu et al. (2005); Spry et al., 2011	BAA5
	Brand X is up-market	Pappu et al. (2005)	BAA6
	I can easily imagine brand X in my mind	Aaker (1991, 1996), Pappu et al. (2005), Washburn and Plank (2002), Yoo and Donthu (2002)	BAA7
	Some characteristics of brand X come to my brand quickly		BAA8
	Brand Belief
	I believe, brand X has good serviceability	Batra and Ahtola (1991); Keller and Aaker (1992); Kim et al. (2014); Kwon and Lennon (2005; 2009; 2009)	BAB1
	I enjoy using brand X		BAB2
	I like the way brand X looks		BAB3
	I believe, brand X appeals to people like me		BAB4
Vanity	I place a high emphasis on my appearance	Hung et al. (2011)	VA1
	It is important that I look good		VA2
	I would feel embarrassed if I was around people and did not look my best		VA3
	My achievement is highly regarded by others		VA4
	I want others to look up to me because of my accomplishments		VA5
	Achieving greater success than my peer is important to me		VA6
Luxury brand Value	Symbolic
	Usage of brand X product will indicate that I am a person with taste	Tsai (2005)	VS1
	Usage of brand X product will prevent me from looking cheap		VS2
	Brand X product will help me to better fit into my social setting		VS3
	Brand X product enhances the perception that I have a desirable lifestyle		VS4
	Experiential
	Luxury Brand X product is rare	Hung et al. (2011)	VE1
	Luxury Brand X product is unique		VE2
	Luxury Brand X product is stunning		VE3
	Functional
	Luxury brand X product has the best quality	Hung et al. (2011)	VF1
	Luxury brand X product is sophisticated		VF2
	Luxury brand X product is superior		VF3
Purchase Intention	I have a strong possibility to purchase brand X’s product	Calvo and Lang (2015); Hung et al. (2011)	PI1
	I am likely to purchase brand X’s product		PI2
	I have high intention to purchase brand X’s product		PI3

.

4. Results

This study employed exploratory factor analysis (EFA) to examine inter-relationships between large numbers of variables, and to describe such variables in terms of their common underlying factors [107]. Initially, 59 items of measures of the thirteen proposed constructs are subjected to EFA. EFA is used to determine the factor structure of measures, scrutinise internal reliability and discover underlying structures in the research variables [125].

Table 3. Study constructs, Cronbach Alpha, scale items, mean, standard variation, and correlation matrix.

Construct		CFA	Loading	Mean	Standard Dev.	Cronbach’s alpha	AVE	Cons. Reliability
Celebrity Credibility
	Attractiveness					0.946	0.886	0.727
		CCA1	0.908	5.5389	1.27330
		CCA2	0.906	5.5331	1.33475
		CCA5	0.845	5.5214	1.32031
	Trustworthiness					0.930	0.871	0.777
		CCT2	0.838	5.4883	1.29809
		CCT3	0.869	5.5097	1.31601
		CCT4	0.879	5.3366	1.47677
		CCT5	0.898	5.3132	1.44595
	Expertise					0.923	0.884	0.726
		CCE1	0.890	5.6012	1.25752
		CCE4	0.902	5.6693	1.30658
		CCE5	0.860	5.6790	1.24098
Familiarity						0.890	0.854	0.719
		FAM1	0.848	5.0233	1.33167
		FAM2	0.865	4.9825	1.36572
		FAM3	0.849	5.0389	1.37311
Attitude towards celebrity endorsement						0.791	0.852	0.810
		AT1	0.812	5.1167	1.40383
		AT2	0.864	5.1245	1.40733
		AT3	0.802	5.2062	1.46175
		AT5	0.902	5.1187	1.47610
		AT6	0.878	5.2665	1.45798
Brand awareness						0.920	0.855	0.719
		BW1	0.861	5.4708	1.44291
		BW2	0.863	5.4883	1.37963
		BW3	0.841	5.4514	1.35025
Brand Attitude
	Brand association					0.736	0.823	0.804
		BAA3	0.729	5.7568	1.20315
		BAA4	0.840	5.9358	1.20013
		BAA5	0.805	5.7354	1.23782
		BAA6	0.830	5.5019	1.30563
		BAA7	0.911	5.5447	1.33441
	Brand Belief					0.933	0.908	0.732
		BAB1	0.918	5.4864	1.38102
		BAB2	0.913	5.5175	1.38661
		BAB3	0.894	5.5564	1.33396
Vanity						0.959	0.925	0.787
		VA1	0.917	5.5214	1.56114
		VA2	0.941	5.4105	1.65927
		VA3	0.891	5.3385	1.55791
		VA5	0.952	5.4319	1.58706
Luxury Brand Value
	Symbolic					0.944	0.831	0.714
		VS1	0.815	5.7101	1.34918
		VS2	0.836	5.8054	1.34102
		VS3	0.843	5.7646	1.28457
	Experiential					0.915	0.903	0.730
		VE1	0.928	5.7179	1.28729
		VE2	0.899	5.6245	1.32933
		VE3	0.881	5.6420	1.36664
	Functional					0.936	0.813	0.709
		VF1	0.834	5.6984	1.28892
		VF2	0.833	5.8755	1.35079
		VF3	0.772	5.8599	1.34056
Purchase Intention						0.935	0.810	0.708
		PI1	0.818	5.6342	1.39844
		PI2	0.812	5.6537	1.41446
		PI3	0.800	5.5331	1.47490

illustrates the item loading (0.729 through 0.952) from the rotated component matrix, which satisfied the minimum criteria for factor loadings and fit within the theoretical factor structures [107]. Furthermore, the results designate that Cronbach’s alpha (0.736 through 0.959) for each factor is internally consistent [124].

Table 4. Correlation matrix for the constructs.

	CCA	CCT	CCE	FAM	AT	BW	BAA	BAB	VA	VS	VE	VF	PI	Age	Degree	Employ.	Gender	Visit
Credibility
CCA	1
CCT	0.247**	1
CCE	0.328**	0.342**	1
FAM	0.015	0.016	0.027	1
AT	0.251**	0.215**	0.187**	0.405**	1
BW	0.416**	0.233**	0.191**	0.071	0.331**	1
Brand Attitude
BAA	0.342**	0.359**	0.325**	−0.045	0.254**	0.335**	1
BAB	0.169**	0.222**	0.179**	−0.048	0.077*	0.118**	0.604**	1
VA	0.087*	0.020	0.021	0.246**	0.216**	0.185**	0.048	0.019	1
Luxury brand value
VS	0.308**	0.320**	0.337**	−0.019	0.364**	0.386**	0.476**	0.134**	0.147**	1
VS	0.062	0.072	0.129**	0.077*	0.157**	0.081*	0.121**	0.091*	0.194**	0.165**	1
VF	0.431**	0.315**	0.315**	0.030	0.319**	0.477**	0.405**	0.081*	0.144**	0.540**	0.250**	1
Purchase Intention	0.375**	0.372**	0.292**	0.018	0.418**	0.368**	0.398**	0.216**	0.160**	0.496**	0.355**	0.503**	1
Age	−0.051	−0.025	0.027	0.014	−0.005	−0.035	0.004	0.029	0.026	0.065	−0.003	0.041	0.006	1
Degree	−0.041	0.015	−0.004	0.048	−0.029	0.039	0.021	0.051	0.013	0.006	0.033	−0.037	−0.013	0.170**	1
Employment	0.031	0.040	0.027	−0.038	0.049	−0.021	0.004	0.005	0.016	0.023	0.072	0.031	0.096*	0.112**	0.001	1
Gender	−0.010	0.039	0.020	0.040	0.032	0.007	0.066	0.052	0.017	0.074*	0.035	0.058	0.058	0.093*	−0.068	−0.203**	1
Visit	0.003	0.072	0.035	−0.024	0.006	0.026	0.013	−0.002	−0.012	0.098*	0.120**	0.120**	0.097*	0.179**	0.099*	0.381**	−0.036	1

**. Correlation is significant at the 0.01 level (1-tailed). *. Correlation is significant at the 0.05 level (1-tailed).

demonstrates that the majority of the independent variables significantly correlated to the dependent variables and the majority of variables are linear with each other. In addition, in this study, to examine the common method bias and a common latent factor, we employed Harman’s one-factor test by using a chi-square difference among the original and fully constrained model [126,127]. The results show that the two models are statistically dissimilar and share a variance, and the original findings of the model were examined without any consideration of method biases.

To examine the research model and hypotheses, this study uses analysis of moment structure (AMOS) 21, confirmatory factor analysis (CFI) and structural equation model (SEM). Based on the recommendation by Hair et al. [107] and Tabachnick and Fidell [125], the model fit is assessed for overall fitness. The results show that root mean squared approximation of error (RMSEA) (0.063 < 0.08) and the comparative fit index (CFI) (0.918 > 0.90) provide sufficient unique information to evaluate a model, which indicates acceptable fit [128]. Tucker-Lewis index (TLI), and the incremental fit index (IFI) indicate satisfactory fit (0.910 and 0.918 > 0.90, respectively) [107]. Furthermore, the goodness-of-fit index (GFI) and the adjusted goodness-of-fit index (AGFI) are below the acceptable cut-off level (0.812 and 0.786, respectively). Based on Hair et al. [107], there is no exact value on any index can distinct models into satisfactory and unsatisfactory fits.

Based on the standardised parameter estimates for the hypothesised associations between the research constructs, the findings, as shown in

Table 5. Results of hypothesis testing.

Standardised Regression Paths				Estimate	C.R	p	Hypothesis
H1	Celebrity Credibility	--->	Attitude towards Celebrity Endorsement	0.871	6.999	***	Supported
H2	Familiarity	--->	Attitude towards Celebrity Endorsement	0.094	1.660	0.097	Not-Supported
H3a	Attitude towards Celebrity Endorsement	--->	Purchase Intention	1.017	2.043	0.041	Supported
H3b	Attitude towards Celebrity Endorsement	--->	Brand awareness	0.425	9.732	***	Supported
H3c	Attitude towards Celebrity Endorsement	--->	Brand Attitude	0.057	1.141	0.254	Not-Supported
H3d	Attitude towards Celebrity Endorsement	--->	Luxury brand Value	0.237	6.124	***	Supported
H4a	Brand awareness	--->	Brand Attitude	0.097	1.882	0.060	Not-Supported
H4b	Brand awareness	--->	Purchase Intention	0.069	1.604	0.109	Not-Supported
H5	Brand Attitude	--->	Purchase Intention	0.983	2.043	0.041	Supported
H6	Vanity	--->	Luxury brand Value	0.068	3.104	0.002	Supported
H7	Luxury brand Value	--->	Purchase Intention	8.070	2.018	0.044	Supported

, offer support for H1 (celebrity credibility -> attitude towards celebrity endorsement) (γ = 0.871, t = 6.999). The relationship between customers perceptions towards celebrity familiarity and attitude towards celebrity endorsement is not statistically significant (γ = 0.094, t = 1.660, p = 0.094), therefore, hypothesis 2 is rejected. Hypotheses H3a (Attitude towards Celebrity Endorsement -> Purchase Intention) and H3b (Attitude towards Celebrity Endorsement -> Brand awareness) (γ = 1.017, t = 2.043; γ = 0.425, t = 9.732, respectively) are supported. However, the results show there is no significant relationship between attitude towards celebrity endorsement and brand attitude (γ = 0.057, t = 1.141, p = 0.254), thus, hypothesis 3c is rejected. Hypothesis 3d shows the direct relationships between attitude towards celebrity endorsement and luxury brand value (γ = 0.237, t = 6.124). With regard to hypothesis H4a and H4b, the results demonstrate that there is no relationships between brand awareness and brand attitude (γ = 0.097, t = 1.882, p = 0.060). In addition, the relationships between brand awareness and purchase intention is found insignificant (γ = 0.069, t = 1.604, p = 0.109).

On the other hand, there is a significant relationship between brand attitude and purchase intention (γ = 0.983, t = 2.043) and the examination demonstrates the significant relationships between vanity and luxury brand value (γ = 0.068, t = 3.104), so, hypotheses H5 and H6 are fully accepted. Regarding hypothesis 7, there is a significant relationship between luxury brand value and purchase intention (γ = 8.070, t = 2.018). The results validate the research model and the hypothesised relationships between the constructs of interest; eight out of the eleven relationships are accepted.

5. Discussion and Theoretical Implications

Based on the aim of our paper and to minimise the gaps, we employed associative network theory and theory of planned behaviour to develop our conceptual model. Our validated model identified the key role of celebrity endorsement, in terms of credibility, familiarity, luxury brand value, and brand sustainability awareness on attitude towards celebrity, brand and purchase intentions to stimulate a sustainable consumption. The findings of this study suggest that most of the hypotheses are confirmed. This study confirms that celebrity credibility has a positive effect on attitude towards celebrity endorsement. These outcomes are in line with the previous studies, where researchers [50,54] have confirmed the positive effects of celebrity credibility on attitude towards celebrity endorsement.

Similarly, H1, H3 have also been confirmed. The literature [63,64] shows that familiarity brings a positive effect on attitude towards celebrity. Similarly, hypotheses H3a, H3b, and H3d, i.e., attitude towards celebrity endorsement effects on purchase intention, brand awareness, and luxury brand value are all confirmed. Previous researchers [31,44,78] have examined the effects of similar constructs effects on purchase attention, brand awareness, and luxury brand. It is evident from their studies that celebrity credibility transfers the positive effects on purchase attention, brand awareness, and luxury brands. However, it is very interesting to comment on the potential meaning of the not-supported hypotheses.

The positive effect of familiarity surprisingly does not impact on attitude toward celebrity endorsement, i.e., H2. This means that the process of familiarity to the celebrity does not ensure a positive influence on attitude toward celebrity revising the process of prior knowledge and information from the familiar celebrity [64].

This study additionally does not confirm the effect of attitude towards celebrity on brand attitude is not confirmed, i.e., H3c, despite most of the previous studies have presented different outcomes [74,129]. This result perhaps reveals that attitude towards celebrity does not have a positive impact on brand attitude because it could be related to other factors, such as attitude toward advertising [68] expressing partial or neutral effect.

Furthermore, brand awareness does not have a favourable impact on both brand attitude and purchase intention, i.e., H4a and H4b These findings are not in line with the previous studies [79,86] demonstrating a different interpretation of the brand awareness in terms of recognition and recall to the brand.

Finally, this study also confirms that brand attitude has a positive on purchase intentions, and vanity has a positive effect on luxury brand value—while luxury brand value has a positive effect on purchase intention. Once again, these findings confirm findings from the previous studies [88,89,101].

6. Managerial Implications, Limitations and Future Studies

As suggested by the current analysis, celebrity endorsement constitutes a relevant tool in building up sustainable firm value, especially in the luxury sector, where consumers demand more and more for sustainable productions, even though they seem not concerned with sustainability when they purchase luxury products. In fact, nowadays, it is not so clear what are the relevant factors which lead customers to prefer or not sustainable luxury products [130]. By paradox, they assume luxury products are made sustainably, as a firm value. It seems that luxury consumers approve sustainable products, but they do not want to verify this sustainability claim. Hence, celebrity endorsement certifies this tension, without directly communicating a sustainable message that may produce refusal effects on the emotional side. On the contrary, this effect can significantly deteriorate when celebrity endorsements are improperly managed. That is, this study has made a number of implications for practitioners.

First and foremost, the results will help managers to understand the effect of celebrity credibility on attitude towards celebrity endorsement. It will help practitioners to understand the importance that the credibility of celebrity brings towards celebrity. The perspective is very relevant when planning the communication strategy towards sustainability that cannot be directly arranged and addressed to the audience, because of its inefficacy. Accordingly, luxury firms that communicate their responsible behaviours by a secondary source, have to pay greater attention to the reputation of the celebrity instead of his/her popularity [131]. Secondly, this study will help practitioners to understand the effects of celebrity familiarity on attitude towards celebrity endorsement. It will help them to recognise that a familiar celebrity increases consumer’s attitude towards a celebrity, which can increase consumers’ preferences. Similarly, this study will help practitioners to understand the value of positive effects of attitude towards celebrity endorsement on purchase intention, brand awareness, and luxury brand value. Managers will be clear on the significant effects of these relationships and will be able to hire familiar and like celebrities, responsible towards the environment and society. This study also provides guidance to managers to understand the importance of brand attitude on purchase intention, which means that consumers’ positive attitude towards brand increases the chances of behavioural intention. Finally, this study will help practitioners to understand the significant positive effects of vanity on luxury brand value, and luxury brand value on purchase intention. These relationships will help managers to understand the crucially and significance of luxury brands on the individual’s social status and consumptions, better understanding the consistent value of inspired sustainability. In our study, vanity and familiarity are considered as independent variables. Future studies could consider vanity and familiarity as either control or moderating variables.

Despite these remarkable suggestions, the study has a few limitations that have provided avenues for future research. First of all, generalisability and validity are “must” requirements. Future studies should be based on this topic in different research settings to resolve the generalisability and validity issues. Secondly, future studies should gather data by using probability sampling, rather than the convenience sampling, which is used in this study and found as a limitation. Next, future studies should bring the boundary conditions, i.e., future studies should be conducted on how consumers’ see the brand and celebrities, when they have high and low credibility and/or presence. Future studies should also be conducted on examining the topic based on international and local celebrities and/or brand. Future studies should also do comparison studies. Finally, future studies could consider the effects of brands and celebrity endorsement on social media (e.g., Instagram), within different countries [132]. Another interesting study could be conducting an experimental study to compare the results of two different brands and their celebrity endorsements through a factorial design study.

In conclusion, given the continuing growth of celebrity endorsements in the luxury sector, this research, with the theoretical and managerial implications discussed above, provides pivotal knowledge to researchers and marketers, but also highlights the challenges and opportunities that luxury brands may have with regard to sustainability, in the awareness that it is not a deferrable goal by now.