The effect of social media influencers on purchase intention: Examining the mediating role of brand attitude

The rapid growth of social media platforms has revolutionized marketing communications, and the recent trend of how people use social media led to the inception of the term "influencer marketing" as an increasingly popular approach for brands across markets. This development has been driven by the unparalleled increase in influencers’ presence on social media platforms


Introduction
The rapid growth of social media platforms has transformed the marketing landscape, as social media marketing has become a popular digital marketing tool in recent years due to increasing number of people using social media (Alrwashdeh, Jahmani, Ibrahim, & Aljuhmani, 2020;Nofal, Bayram, Emeagwali, & Al-Mu'ani, 2022).It is no wonder that marketing managers began to realize social media platforms as key channels to achieve many of the company's goals and strategies (Lou & Yuan, 2019).
Influencers, who are ordinary people that have gained fame online for their expertise in a specific field, such as food, fashion, technology, travel, education, music, and movie reviews (Lou & Yuan, 2019), have become an increasingly popular way for businesses to promote their products or services.The rise of influencers has contributed to the emergence of the term "influencer marketing" as a fast-growing part of marketing communications strategy for brands in various product categories.Businesses looking to increase their customer base and cultivate a long-term relationship with their customers (Aramburu & Pescador, 2019).Consumers are more likely to believe and accept the influencers' point of view because they voluntarily choose to follow those influencers (Gomes, Marques, & Dias, 2022).This growth has been driven by the unparalleled increase in influencers' presence on social media platforms, which has generated novel prospects for companies to connect with their desired demographic and interact with them in a more genuine and significant manner (Campbell & Farrell, 2020;Haenlein et al., 2020).Grasping the aspects that impact the success of influencer marketing is growing in importance for both marketing professionals and researchers.It is determined by various factors, including the characteristics of influencers themselves, such as their trustworthiness, expertise, and the quality of the information they provide (Vrontis, Makrides, Christofi, & Thrassou, 2021).These factors have been found to influence consumers' brand attitudes and purchase intentions, which are critical for businesses that harness influencer marketing (Kurdi et al., 2022).Furthermore, brand attitude emerges as a central construct in consumer behavior research, as it significantly influences consumers' purchase intentions and actual buying behavior (Park, Jeon, & Sullivan, 2015;Singh & Banerjee, 2018) as a positive brand attitude can lead to increase purchases, while a negative one can deter potential customers and harm the brand's reputation (Reinikainen, Tan, Luoma-aho, & Salo, 2021).
Numerous studies have been conducted on the topic of celebrity endorsements.However, the use of "traditional" celebrities, including actors, athletes, musicians, and models, is losing its appeal in the digital era of social media, as brands increasingly turn to social media influencers instead (Schouten, Janssen, & Verspaget, 2020).Because it is a cost-effective alternative to traditional celebrity endorsements (Taillon, Mueller, Kowalczyk, & Jones, 2020), and it has been found to be more effective in shaping consumer behavior (Schouten et al., 2020).Nonetheless, there is still a lack of understanding about how marketers can effectively utilize this new marketing phenomenon (Campbell & Farrell, 2020).The success of influencer marketing is still in its early stages (Chekima, Chekima, & Adis, 2020).To enrich the literature and aid marketing practices, a more indepth and comprehensive explanation of this phenomenon is necessary (Hmoud, Nofal, Yaseen, Al-Masaeed, & Alfawwaz, 2022;Vrontis et al., 2021).As a result, this study aims to examine the role of trustworthiness, expertise, and information quality of social media influencers in shaping consumer purchase intention, with a specific focus on the mediating role of brand attitude.By investigating these relationships, this research seeks to contribute to the existing literature on influencer marketing and provide valuable insights for businesses looking to optimize their influencer marketing strategies.

Trustworthiness
Trustworthiness of an influencer refers to the degree to which consumers perceive an influencer as reliable, honest, and credible in their endorsements, recommendations, or opinions about products and services (Abdullah et al., 2020).Trust is a crucial factor in influencer marketing, as it directly influences consumers' perceptions of the messages delivered by opinion leaders and affects their behavior (Casaló, Flavián, & Ibáñez-Sánchez, 2020).When consumers perceive an influencer as trustworthy, they are more likely to be receptive to their messages, engage with their content, and follow their recommendations, ultimately resulting in increased purchase intentions (Lou & Yuan, 2019).Similarly, Saima & Khan (2020) found that trust in influencers positively influenced consumers' purchase intentions and influencer's credibility.Additionally, in qualitative research conducted by Djafarova and Rushworth (2017), they found that online celebrities' trustworthiness significantly affects young females' purchase intentions.
Therefore, we hypothesized that: H1: Trustworthiness of the influencer influences purchase intention.
Previous studies found Influencer trustworthiness plays a significant role in shaping consumers' brand attitudes.Exploring the impact of influencer trustworthiness on brand attitude, lead to mixed results.Several studies have found a positive impact of influencers' trustworthiness on brand attitude.For instance, Chekima et al. (2020) discovered that trust influences product attitude.Similarly, Nafees, Cook, Nikolov, & Stoddard (2021) found that trust affects product attitude, and Hmoud et al. (2022) also found similar results for the Jordanian consumers.However, not all studies have found the same results.For instance, Dhun & Dangi (2022) did not find a significant relationship between trust and brand attitude.Understanding the impact of influencer trustworthiness on brand attitude will be crucial for marketers when selecting endorsers and designing effective marketing strategies.Therefore, we hypothesized that: H2: Trustworthiness of the influencer influences brand attitude.

Expertise
The influencer's expertise refers to the perceived knowledge, experience, and competence of an influencer in a particular domain or industry (Ohanian, 1990).Expertise is an essential component of source credibility, and it can influence consumers' perceptions and receptivity to the messages conveyed by the sender (Hovland, Janis, & Kelley, 1953).When an influencer is perceived as an expert in their domain, consumers are more likely to trust their recommendations, opinions, or endorsements, which, in turn, can increase their purchase intentions (AlFarraj et al., 2021).Expertise can enhance the persuasive power of the influencer's message and the likelihood of consumers adopting their suggestions (Shen, 2021).In addition, empirical studies have shown mixed results regarding the impact of influencers' expertise on purchase intention.For instance, several empirical studies have investigated the impact of influencers' expertise on purchase intention, but the results have been mixed.Lou & Yuan (2019) did not find a direct effect of expertise on purchase intention, while AlFarraj et al. (2021) did not find such an effect in the aesthetic dermatology industry, and Gomes et al. (2022) did not find it in relation to fashion products.Similarly, Widyanto & Agusti (2020) found similar results among Generation Z consumers in Indonesia.However, other studies have found positive effects.For example, Abdullah et al. (2020) found positive results in the fashion industry.Likewise, Weismueller, Harrigan, Wang, & Soutar (2020) found the relation positive in the German cosmetics market.Also, Hmoud et al. (2022) found the same results for Jordanian consumers.These findings suggested that expertise had an effect on purchase intention across many markets.By demonstrating their expertise in their domain, influencers can gain the trust of their audience, increasing the likelihood of consumers making purchases based on their recommendations.Therefore, we hypothesized that:

H3: Expertise of the influencer has an effect on purchase intention.
Previous studies have highlighted the importance of expertise in influencing brand attitudes.expertise refers to the extent to which a speaker is perceived as capable of making correct assertions (Hovland et al., 1953).According to Source Credibility Theory, the effectiveness of a persuasive message depends on the credibility of the source, including their expertise and trustworthiness (Hovland et al., 1953).In other words when an influencer is perceived as an expert in their domain, the message they convey about a brand is more likely to be accepted and internalized by the audience, resulting in a more favorable brand attitude.The consistent findings from various research articles emphasize the importance of influencer expertise on shaping brand attitude.Chekima et al. (2020) found that the expertise of the influencer is affecting product attitude in the cosmetic industry.Also Dhun & Dangi, (2022) supported the hypothesis.While in the Jordanian culture Hmoud et al. ( 2022) found similar results.Influencers with perceived expertise in their respective fields can provide valuable information to their audience, ultimately influencing brand attitudes and potentially impacting purchase decisions.Therefore, we hypothesized that: H4: Expertise of the influencer has an effect on brand attitude.

Information quality
Information quality refers to the accuracy, reliability, relevance, and comprehensiveness of the information presented to consumers (Wang & Strong, 1996).Information quality is a critical aspect of social media marketing messages, as it encompasses the accuracy, authenticity, and believability of the content (Appelman & Sundar, 2016).(Erkan & Evans, 2016;Esteban-Santos, García Medina, Carey, & Bellido-Pérez, 2018) has found that the perceived quality of electronic word-of-mouth (eWOM) information positively influences information usefulness, adoption, and purchase intention.Similarly, Magno (2017) argues that high-quality content, such as that found in blogs, leads to stronger engagement and increased purchase intention for recommended products.Van-Tien Dao, Nhat Hanh Le, Ming-Sung Cheng, & Chao Chen (2014) in their study verified that advertising value, which was determined by the perceived informativeness, entertainment, and credibility of the advertisement, had a significant impact on consumers' purchase intentions.In the context of influencer marketing, the quality, originality, and uniqueness of posts have been identified as key factors in developing opinion leadership (Casaló et al., 2020).Djafarova & Rushworth (2017) also found that quality of posts is essential for users' decisions to follow digital influencers.Influencers generate regular social media updates with both informational and entertainment value (Lou & Yuan, 2019).How followers respond to branded posts can be influenced by how they perceive the informative value of the content.In addition, many empirical studies have shown varying results on the effect of influencer information quality on purchase intention.(Hmoud et al., 2022) in the Jordanian market, (Gomes et al., 2022) in fashion products, and (Lou & Yuan, 2019)found that influencer information quality had a significant effect on purchase intention.However, Saima & Khan (2020) did not find an effect in their study.Therefore, we hypothesized that:

H5: Information quality of the influencer has an effect on purchase intention.
The continuous presence of social media influencers and their unique marketing model, (Alrwashdeh, Ali, Helalat, & Alkhodary, 2022;Xiao, Wang, & Chan-Olmsted, 2018), highlights the importance of perceived information credibility in shaping consumer attitudes towards brands and products mentioned in their content.Wang, Walther, Pingree, & Hawkins (2008) have similarly shown that the credibility of information sources can have a positive impact on consumer attitudes.Tseng, Chang, & Zhu (2021) found that the quality of information can influence consumer satisfaction and trust.Chen & Chang (2018) found that detailed, high-quality information can significantly increase consumer interest and satisfaction.Moreover, drawing on the findings from various studies in influencer marketing context, it is evident that information quality provided by the influencer plays a crucial role in shaping consumers' attitudes towards brands.(Amagsila, Cadavis, Callueng, & Manio, 2022;Hmoud et al., 2022;Xiao et al., 2018) have all demonstrated a positive relationship between information quality and brand attitude.Therefore, we hypothesized that: H6: Information quality of the influencer has an effect on brand attitude.

Brand attitude
Brand attitude refers to a consumer's overall evaluation of a brand, which is influenced by their responses to stimuli associated with the brand (Eagly & Chaiken, 1993).According to the theory of planned behavior (Ajzen, 1991), attitudes towards a brand play a significant role in determining consumers' intentions to purchase a particular product.The literature supports the hypothesis that brand attitude affects purchase intention.Mackenzie & Spreng (1992) suggest that brand attitudes enhance purchase intentions as consumer motivation increases.Several models, such as the 'elaboration likelihood model' (Petty & Cacioppo, 1986), the 'technology acceptance model' (Davis, 1985), and the 'Hierarchy of Effects Model' (Lavidge & Steiner, 1961), reinforce this view.In the context of influencer marketing, Hughes, Swaminathan, & Brooks (2019) highlight the importance of hedonic value in sponsored posts, leading to higher engagement.Additionally, Hwang & Zhang (2018) found that perceived similarity with the influencer can lessen the negative impact of persuasion awareness.Thus, understanding consumers' attitudes towards sponsored posts is crucial in determining their effect on purchase intention.Empirical research further supports the relationship between brand attitude and purchase intention.(Gomes et al., 2022;Hmoud et al., 2022;Park et al., 2015;Singh & Banerjee, 2018) all found a significant effect of brand attitude on purchase intention.Therefore, we hypothesized that: H7: Brand attitude has an effect on purchase intention.
The role of brand attitude as a mediator in the relationship between various factors and purchase intention has been studied extensively in literature.Lafferty & Goldsmith (1999) contributed to the study of brand attitude's role as a mediator, the study indicated that the impact of source characteristics such as attractiveness and expertise on purchase intentions is influenced by brand attitude, indicating a mediating role of brand attitude.According to their findings, source characteristics, such as attractiveness and expertise, do not have a direct significant effect on purchase intentions.However, these characteristics positively affect brand attitude, which in turn leads to purchase intentions.Rup, Gochhayat, & Samanta (2021) found that brand attitude mediates the relationship between brand personality and purchase intention.More recent literature has continued to explore the mediating role of brand attitude in the context of influencer marketing.Gomes et al. (2022) found that brand attitude mediates the relationship between digital influencers' characteristics and purchase intention.Similarly, Trivedi & Sama (2020) discovered that brand attitude mediates the impact of influencers and celebrities on purchase intention.Furthermore, Hmoud et al. ( 2022) further supports the mediating role of brand attitude, reporting that the positive effects of influencers' attributes on purchase intention are channeled through brand attitude, with all indirect effects being significant.while Su, Wu, Lin, & Lin (2023) found that brand attitude mediates the effect of influencer credibility and purchase intention.Therefore, we hypothesized that: H8: Brand attitude mediates the relationship between (H8a.trustworthiness, H8b.expertise, and H8c.information quality) of the influencer and purchase intention.

Sampling
In Jordan, social media is widely used, with over 6.84 million users, accounting for 61.5% of the population (Kemp, 2021).Facebook is the most popular platform, with 5.5 million users.The research was conducted using an online questionnaire, which included questions about demographics and variables related to the study.A total of 309 complete responses were collected via convenience sampling between January and February 2023 then the researchers used SPSS and AMOS for analysis purposes.Regarding the sampling demographics as shown in Table (1), the most age group of the sample were between 18-25 (35.92%) and 26-32 (27.18%) years old.Most respondents follow 4-5 influencers (31.72%) for getting information about products or services, and primarily use YouTube (47.25%) then Instagram (23.95%).The majority (85.11%) of the respondents search for more information after receiving recommendations from their favorite influencers.

Convergent validity
To ensure the accuracy of the model, various metrics such as factor loading, composite reliability (CR), and average variance extracted (AVE) were employed to establish convergent validity.Table 2 displays the findings, showing that all measurement loadings surpass the necessary 0.6 benchmark, (CR) exceed 0.7, and (AVE) above 0.5.Additionally, to confirm that the indicators are not linearly dependent, VIF values were calculated and found to be within the recommended limit of 5 as suggested by (Hair, 2009), ranging from 1.02 to 1.27.

Discriminant validity
According to Fornell and Larcker (1981), the (AVE) can be used to assess the discriminant validity.The results presented in Table 3 demonstrate that all correlation values are lower than the square root of (AVE) values, implying that the model has appropriate discriminant validity.

Model Fit
Numerous fit indices assess the model's fit.The researchers followed Hu & Bentler (1999) guidelines as shown in Table 4).
The results revealed that all the values met the corresponding threshold, demonstrating a robust fit for the model.

Table 4
The summary of the fit model

Hypotheses testing
Table 4 shows that researchers find out that all hypotheses were supported, the expertise of the influencer has the most effects on brand attitude β= 0.407, then come the trustworthiness with β= 0.197, and lastly came the information quality that the influencer provided on brand attitude with β= 0.13.In addition, trustworthiness of the influencer has the most effect on purchase intention with β= 0.325, while Expertise, Information Quality, and Brand Attitude have also significant effects with β values (0.192, 0.149, 0.171) respectively.Furthermore, the model explained 30% of the variance of purchase intention based on the variables in the model (R 2 =0.3).The results of the hypothesized direct effects are presented in Table 5, which indicates that all the hypotheses were accepted.Furthermore, after conducting bootstrapping with 95% confidence interval, Table 6 shows that all indirect effects were significant on purchase intention via brand attitude.Therefore, H8a, H8b, and H8c were supported.However, brand attitude only partially mediates the relationships, as all direct relationships were supported.

Discussion
The aim of this study was to investigate the effects of influencer attributes (trustworthiness, expertise, and information quality) on consumers' brand attitude and purchase intention.The study also aims to investigate the mediation role of brand attitude in the connections between influencer attributes and buying intentions.By comprehending these connections, the research intends to offer valuable insights for marketers and influencers to create more efficient influencer marketing tactics and content that can positively impact consumers' attitudes towards the advertised brands and their propensity to buy the promoted products.The findings reveal that trustworthiness, expertise, and information quality have a significant influence on purchase intention (H1, H3, and H5) and brand attitude (H2, H4, and H6).These results imply that an influencer's credibility and the information quality they offer are crucial in shaping consumers' attitudes towards the advertised brands and their willingness to buy the promoted products.
Our research indicates that consumer trust in influencers is essential for the success of influencer marketing approaches since it shapes consumers' perceptions and receptiveness to the content and suggestions provided by influencers.Trustworthiness acts as a catalyst for consumer engagement, as people who view an influencer as trustworthy are more likely to interact with their content and follow their recommendations (Lou & Yuan, 2019).The findings align with previous research that has shown a significant association between influencer trustworthiness and consumer purchase intentions (Casaló et al., 2020;Djafarova & Rushworth, 2017;Lou & Yuan, 2019;Saima & Khan, 2020).
Moreover, the research reveals a considerable impact of influencer expertise on consumers' buying intentions, contributing to the ongoing discussion in the literature about the role of expertise in influencer marketing.Our results are consistent with studies by (Abdullah et al., 2020;Hmoud et al., 2022;Weismueller et al., 2020), which found a positive influence of influencer expertise on purchase intention across various industries and regions.However, our findings differ from those of (AlFarraj et al., 2021;Gomes et al., 2022;Lou & Yuan, 2019;Widyanto & Agusti, 2020), who did not discover a significant effect of influencer expertise on purchase intentions.The contradiction in results may come from the specific targeted sample in these studies.For example, the lack of impact of expertise on purchase intention among Generation Z consumers in Indonesia (Widyanto & Agusti, 2020) might be due to the unique characteristics of this demographic group and their preferences.
The results also found a significant impact of the information quality provided by influencers on consumers' purchase intentions, contributing to the mixed findings in the literature concerning the role of information quality in influencer marketing context.Our results are in line with the findings of (Gomes et al., 2022;Hmoud et al., 2022;Lou & Yuan, 2019) emphasize the importance of providing high-quality, original, and informative content in shaping consumers' purchasing decisions.When influencers share informative content, consumers are more likely to perceive their recommendations as valuable, ultimately leading to increased purchase intentions.However, (Saima & Khan, 2020) did not find a significant effect of information quality on purchase intention.This difference in results may be due to differences in the industries examined, and cultural differences among the studies' population.
Another aim of the study was to find the effect of influencer's attributes on brand attitude.Our research findings indicate that (trustworthiness, expertise, and information quality) significantly affect brand attitudes.Our results are consistent with (Amagsila et al., 2022;Chekima et al., 2020;Dhun & Dangi, 2022;Hmoud et al., 2022;Nafees et al., 2021;Xiao et al., 2018).These findings suggest that when consumers perceive an influencer as trustworthy, expert, and provide informative content, they are more likely to develop positive attitudes towards the brands endorsed by that influencer.It also can effectively convey the desirable attributes of a product and services, thereby positively influencing consumers' evaluations and perceptions of the brand.The last aim of this study was to investigate the mediating role of brand attitude in the relationships between (trustworthiness (H8a), expertise (H8b), and information quality (H8c)) and consumers' purchase intentions.Brand attitude effectively carries the effects of the influencer's attributes to purchase intention.Our findings confirmed the conclusions drawn by (Gomes et al., 2022;Hmoud et al., 2022;Su et al., 2023;Trivedi & Sama, 2020).These findings highlight the importance of considering brand attitude as a key mechanism through which influencers' trustworthiness, expertise, and information quality influence consumers' purchasing decisions.When consumers perceive an influencer to be trustworthy, knowledgeable, and capable of providing high-quality information, they are more likely to develop favorable attitudes towards the promoted brands, which in turn leads to increased purchase intentions.

Implications, limitations and future research
This study's findings hold significant implications for both marketers and influencers.For marketers, grasping the factors that affect consumers' buying intentions and brand attitudes can guide the development of more successful influencer marketing strategies.By choosing influencers with strong trustworthiness, expertise, and information quality, marketers can boost the probability of consumers adopting influencers' suggestions, resulting in increased purchase intentions and improved brand attitudes.Furthermore, marketers should encourage influencers to supply high-quality, accurate, and pertinent information in their content, as this can further strengthen consumers' brand attitudes and buying intentions.
For influencers, the results indicate that establishing trust, showcasing expertise, and offering high-quality information are essential for engaging and influencing their audience.Concentrating on these factors allows influencers to bolster their credibility, generate impactful content, and ultimately enhance their ability to drive consumers' purchasing decisions and shape their attitudes towards the promoted brands.Consequently, influencers who successfully accomplish these goals will become more appealing to brands looking for effective endorsers for their advertising strategies, leading to potentially profitable partnerships.Additionally, this study presents several significant theoretical contributions to the current literature on influencer marketing, as this topic needs more studies to fulfill (Campbell & Farrell, 2020;Chekima et al., 2020;Hmoud et al., 2022;Vrontis et al., 2021).By examining the mediating role of brand attitude in the connection between influencer attributes, such as trustworthiness, expertise, and information quality, and purchase intention, the study offers a more profound comprehension of the underlying mechanisms through which influencer marketing impacts consumer behavior.It provides a comprehensive framework for investigating the effects of influencer attributes on consumers' buying intentions and brand attitudes.Additionally, the study emphasizes the significance of positive brand evaluations in converting the perceived trustworthiness, expertise, and information quality provided by influencers into purchase intentions.
Despite this study's contributions to the literature on influencer marketing, there are a few limitations to consider.The study concentrated on a limited number of influencer attributes.Other potentially relevant attributes, such as attractiveness, relatability, or engagement level, may also influence consumers' brand attitudes and buying intentions and should be examined in future research.Additionally, the study did not focus on a specific product category or social media platform.Conducting similar research in distinct product categories and social media platforms could yield different results and contribute to a more comprehensive understanding of the relationships between influencer attributes, brand attitude, and buying intentions.Finally, the study does not account for the potential moderating effects of individual differences, like age, gender, or prior experience with influencer recommendations.

Fig
Fig. 1.Research model 3. Methodology and Analysis

Table 1
Personal characteristics of the participants

Table 2
Convergent validity results

Table 5
Hypotheses results (Direct Effect)