Effects of Type of Source (Brand vs. Sponsored-User) of an Instagram Post
on Brand Attitude
The Mediating Roles of Attitude Toward the Post, Source Similarity, Trustworthiness, and Expertise
Silvana Vlasblom
Student number: 11168226
Master Thesis
Graduate School of Communication Persuasive Communication
University of Amsterdam
Supervisor: Dr. Young-Shin Lim
June 2017
Abstract
Over the last few years, researchers have explored effects of sponsorship in posts (Mutum & Wang, 2010; Lu, Chang, & Chang, 2014). However, past research has focused on sponsored and non-sponsored posts. Currently, little research has been done focusing on the comparison between brand posts and sponsored-posts by a user. Therefore, there is still a gap in the sponsorship literature. To gain more insight into the sponsorship literature, this study investigated source effects on brand attitude and the mediating roles of attitude toward the post, source similarity, trustworthiness, and expertise.
A total of 175 participants participated in an online experiment. Participants were randomly exposed to either a brand post or a sponsored-post (female, male or neutral source). This study found that attitude toward the post mediates the relationship between type of source and brand attitude. A brand post leads to a more positive attitude toward the post than a sponsored-post, which in turn is positively related to brand attitude. Furthermore, also expertise acts as a mechanism between type of source and brand attitude. A brand post leads to a greater perception of expertise than a sponsored-post, which in turn is positively related to brand attitude. Furthermore, a greater perception of source similarity and trustworthiness is positively related to brand attitude.
Based on these findings, brands gain more insight into the effectiveness of brand posts versus sponsored-posts on brand attitude. Therefore, this study contributes to the field of online marketing communication related to Instagram. However, since the present study is one of the first studies in this area it is interesting for future research to dig deeper into source effects and underlying mechanisms.
Key words: type of source, brand post, sponsored-user, sponsored-post, brand attitude,
Introduction
Social media advertisement refers to online advertising that focus on social networking services, such as Facebook, Twitter, YouTube, and Instagram (Rodgers & Thorson, 2017). It has opened up a new era for marketing management in which online marketing communication is the most changed factor that has witnessed the potential impact of social media. Therefore, marketers’ focus is now on social media in order topromote products and/or services, provide instant support, and create an online community through all forms of social media such as social networking sites, content communities, blogs, forums, and more (Kaplan & Haenlein, 2009). However, social media also enables consumers to share information about brands, products and/or services (Mangold & Faulds, 2009). This provides companies another effective way to promote their brand, products and/or services (Gunelius, 2011). However, which strategy (brand versus consumers) is the most effective?
Among the various social media platforms this study will focus on Instagram. Instagram is one of the fastest-growing online photo social web services where users share their life images with other users. Furthermore, Instagram reported more than 600 million monthly active users (Statista, 2016, December). Individuals spend more time on Instagram than other similar sites, suggesting it is of importance to research this media type (Sheldon & Bryant, 2016).
Brands also started to notice Instagram’s importance. They use Instagram to build and strengthen relationships with consumers (Fred, 2015). For example, brands regularly update content such as product-related posts to attract Instagram users. In 2016, brands posted 4.9 times per week on Instagram, which is an increase of more than 50 percent over 2015
(Forrester, 2015, October).However, brands’ attempt to engage more with consumers, there has been a shift of power between brands and consumers (Burmann & Arnhold, 2009). Brands are increasingly viewed as less authentic and consumers are becoming more
empowered.
Furthermore, consumers trust peer consumers more than they trust brands (Lee & Koo, 2012). Therefore, brands rely more on user-generated content branding (Djafarova &
Rushworth, 2017). User-generated content branding refers to media content created by members of the general public and includes any form of online brand-related content created, initiated, circulated, and consumed by users (Daugherty, Eastin, & Bright, 2008; Smith, Fischer, & Yongjian, 2012). For example, customer’s reviews and photos of products are posted on the brand’s websites or social media accounts. In addition, everyday users promote brands, products and/or services via their own social networks (Geurin & Burch, 2016). Often times, brands encourage those users to spread messages about the brand or product in
exchange for benefits. Those messages, so called “sponsored-posts” are consumer-generated posts, but sponsored by a brand (Mutum & Wang, 2010).
Over the last few years, researchers have explored effects of sponsorship on people’s response to user-generated contents (Mutum & Wang, 2010; Lu et al., 2014). However, past research mostly focused on sponsored and non-sponsored posts. According to Lu et al. (2014) social media posts are a useful marketing communication tool and a vital source in the
process of consumer purchase decision-making. Therefore, understanding of how sponsorship influences consumer’s attitudes is crucial. However, little research has been done focusing on the comparison between brand posts and sponsored-posts. Therefore, there is still a gap in the sponsorship literature. It is of high importance to investigate brand posts versus sponsored-posts for theoretical and practical purposes in the field of online marketing communication. Currently, more and more brands are present on social media, in particular Instagram.
According to LePage (2015) over 85% of top brands use Instagram as part of their marketing strategy. Furthermore, 50 percent of the Instagram users follow at least on brand, 60 percent of them say that they learn about a product and/or service on Instagram, and 75 percent of the
Instagram users take action after looking at an Instagram advertising post, such as visiting a website (Instagram Advertiser Statistics, 2016, September).Therefore, companies are increasingly investing in social media, indicated by worldwide marketing spending on social networking sites of about $23.68 billion in 2015 and will reach $35.98 billion in 2017
(eMarketer, 2015, April). Additionally, companies spend between $1 and $1.5 billion per year on sponsored-content on Instagram (Ma, 2015). For this reason, companies’ expenses will only increase when using sponsored-users instead of posting themselves. Therefore, it is important for businesses to decide which strategy (brand posts vs. sponsored-user posts) is the most effective to promote their products and/or services.
Currently, research found contradicting findings regarding sponsorship. Previous research found that consumers did not seem to care if a consumer-generated advertisement is created for personal gain (Lawrence, Fournier, & Brunel, 2013). They were only interested in that the ad came from a consumer instead of a brand. A study by Campbell, Mohr, and
Verlegh (2013) found that consumer’s attitudes toward the brand became less favorable when the post was sponsored. However, this research focused on sponsored-posts versus non-sponsored posts. Results might differ when taking brand posts into account. Therefore, the first aim of this research is to gain insight into the relation between type of source (brand vs. sponsored-user) and brand attitude on Instagram.
Furthermore, studies have explored the different mechanisms through which type of source (brand vs. sponsored-user) may influence brand attitude. Brand attitude is the constant preference of the consumer towards a certain brand and the overall evaluation the consumer has towards the brand (Fishbein & Ajzen, 1980). It is an important variable in marketing and advertising research because it is considered to be a stable predisposition in predicting consumer behaviour (Mitchell & Olson, 1981). The present study focuses on four potential mechanisms that may mediate the relationship between type of source (brand vs.
sponsored-user) and brand attitude.
First, attitude toward the post might mediate the relationship between type of source (brand vs. sponsored-user) and brand attitude. Based on MacKenzie, Lutz, and Belch (1986) consumer attitudes toward the post are predispositions to respond in a favorable or
unfavorable manner to the Instagram post. According to Mitchell and Olson (1981) attitude toward the ad has a mediating influence on brand attitude. Furthermore, source similarity might mediate the relation between type of source (brand vs. sponsored-user) and brand attitude. Source similarity is the degree in which the recipient of the message corresponds with the qualities, characteristics, and shares values with the source of the message (Eyal & Rubin, 2003). Wilson and Sherrell (1993) showed that when members of a target audience are more likely to identify with the source, they therefore adopt the opinions of similar others. In addition, trustworthiness might mediate the relationship between type of source (brand vs. sponsored-user) and brand attitude. Trustworthiness is the listener’s degree of confidence in, and level of acceptance of, the speaker and the message (Ohanian, 1990). According to
Thompson and Malaviya (2013) consumers do not necessarily perceive consumer ads as more trustful than ads created by brands. They found that an advertising message from a consumer could hinder trustworthiness, which lead to a decrease of ad and brand evaluations.
At last, expertise might mediate the relation between type of source (brand vs. sponsored-user) and brand attitude. Expertise is the extent to which a communicator is perceived to be a source of valid assertions (Ohanian, 1990). Amos, Holmes, and Strutton (2008) found that expertise could increase brand attitude, when individuals perceive the source as an expert. Moreover, the second aim of this research is to gain insight into the mediating roles of attitude toward the post, source similarity, trustworthiness, and expertise.
To summarize, this research aims to contribute to the online marketing communication literature by empirically testing source effects on brand attitude. It will provide insight into
how the source of a brand-related post on Instagram (brand vs. sponsored-user) affects viewer’s brand attitude and the mediating roles of attitude toward the post, source similarity, trustworthiness, and expertise.
Theoretical framework Social media marketing
Social media marketing is a form of Internet marketing that implements various social media networks such as Facebook, Twitter, YouTube, and Instagram in order to achieve marketing communication and branding goals (Kaur, 2016). It primarily covers activities involving social sharing of contents, videos, and images for marketing purposes. Social media marketing is a new trend and rapidly growing in a way in which businesses are reaching out to customers easily (Kaur, 2016).
Furthermore, social media marketing has several advantages (Kaur, 2016). First, the main advantage of social media marketing is cost related. The majority of social media sites are free to access, post information, and create profit.Therefore, the financial barriers to social media marketing are relatively low compared to other marketing strategies. Second, social media has increased social interaction. Third, social media creates interactivity, which gives greater access to information as well as increased engagement.At last, social media provides marketers the ability to target consumers based on their personal interests.
Based on the advantages, social media advertising is of high importance for online marketing communication. However, specific social media networks may change over time or replaced by others, it seems valuable to address social media by looking at the specific
platforms people use. This study will focus on Instagram.
Instagram is a social media platform that has become the fastest-growing social network, with more than 600 million active users (Statista, 2016, December). Instagram is a
mobile device application designed for sharing lifetime moments through photos in real time (Instagram, 2015). It allows users to take photos, enhance them with filtering technology, share them with followers, and comment or like other users’ photos.
This platform is also a useful venue for marketing and advertising, with brands continuing to develop ways to increase user engagement (Ashley & Tuten, 2015). According to Sheldon and Bryant (2016) individuals spend more time on Instagram than other similar platforms. Furthermore, it has “a great impact on the strategic communication objectives such as to create awareness, build relations and strengthen the brand” (Andersson, 2015, p.32). Additionally, it can be used to increase brand recognition as well as the engagement between consumers and the brand (Katona & Savary, 2014). Brands can also use Instagram to build and strengthen relationships with consumers (Fred, 2015). In contrast to Facebook, Instagram does not have an easy way to share information, such as the “share” button. It is rather a consumer/user-oriented platform, and brands rely more on user-generated content branding (Djafarova & Rushworth, 2017). Brands and consumers are encouraged to create content instead of sharing posts. For example, posting photos of products on their own Instagram account (Geurin & Burch, 2016).
Brand attitude
Attitude is an overall evaluation towards people, things, or goods. It is either a positive or negative reaction towards certain things through learning, which includes favorable or unfavorable evaluation, emotional feeling, and behavioral tendency (Hawkins, Best & Koch 2007; Kotler & Keller, 2008). Brand attitude is the constant preference of the consumer towards a certain brand and the overall evaluation the consumer has toward the brand (Fishbein & Ajzen, 1980). The evaluations are based on the benefit or image of the brand. The consumer judges whether the benefit or image is beneficial and then forms an overall attitude toward the brand (Mackenzie & Spreng, 1992). All in all, attitude is an important
variable in marketing and advertising research because it is considered to be a relatively stable predisposition, which is a useful predictor of consumers’ behavior toward a product or a service (Mitchell & Olson, 1981).
Type of source (brand vs. sponsored-user) and brand attitude
Nowadays, brands generate content aiming to advertise and provide product
information to customers through the Web and social network sites (Goh, Heng & Lin, 2013). For example, brands regularly update content such as product-related images and posts to attract people using Instagram. In 2016, brands posted 4.9 times per week on Instagram, which is an increase of more than 50 percent over 2015(Forrester, 2015, October).However, there has been a shift between brands and consumers (Burmann & Arnhold, 2009). With the advent of social media, brands have lost their central role in creating brand stories (Kuksov, Shachar, & Wang, 2013). Instead, consumers have now the ability to share their brand stories easily and widely through social media. Therefore, brands are now increasingly viewed as less authentic and consumers are becoming more empowered. In addition, brands have been witnessing a downward trend in consumers’ trusting perceptions towards traditional
advertising (Nielsen, 2015). Consumers urge brands to seek for new ways to promote their brand, products and/or services.
A new way of promoting brands, products and/or services is to engage and involve consumers. An increasing number of brands have begun encouraging consumers to create brand-related content both in online and offline settings. For example, everyday users promote brands, products and/or services via their own social networks. Additionally, consumers’ reviews and photos of products are posted on the brand’s websites and social media accounts. In this way brands are not the creators of advertising but the consumers.
Often times, consumers are encouraged by the brand to spread messages about the brand, product and/or service in exchange for benefits. Those messages, so called “sponsored
posts” are consumer-generated posts, but sponsored by a brand (Mutum & Wang, 2010). Sponsored posts are different from general product review posts in that sponsored posts are produced based on sponsorship, whereas no such sponsorship is provided for general product review posts. Sponsored posts typically have a more positive attitude toward the product and/or service, because brands often provide users direct monetary compensation or indirect compensation such as free products to encourage production of sponsored posts (Lu et al., 2014). Thus, sponsored users are incentivized to post about a brand, product and/or service.
Furthermore, recent research found that consumers trust peer consumers more than they trust brands (Lee & Koo, 2012). They are more likely to use information provided by other consumers to evaluate products or services. However, Campbell et al. (2013) found that a sponsored-post decrease the consumers’ attitude towards the brand featured in the post. This is in contrast to research from Lawrence et al. (2013) who found that consumers did not seem to care if a consumer-generated advertising is created for personal gain. They were only interested in that the ad came from a consumer instead of a brand. Additionally, Bickart and Schindler (2001) found that sponsored-post are more persuading due to the assumption that consumer reviews are more useful than commercial campaigns. Therefore, in the context of this study, it is expected that consumers will have more favorable brand attitude when they view a sponsored-post than when they view a brand post. This results into the following hypothesis:
H1: A sponsored-post by a user will lead to a more positive brand attitude than a brand post.
Attitude toward the post
According to MacKenzie et al. (1986, p. 46) consumer attitudes toward advertisement are “a predisposition to respond in a favorable or unfavorable manner to a particular
advertising state that consumers’ attitude towards advertising is an essential determinant of its effectiveness (Chen, Fay, & Wang, 2011). Furthermore, past research found that attitude toward the ad has a mediating influence on brand attitude (Mitchell & Olson, 1981; Shimp, 1981). It can provide information about an advertisement’s attitudinal impact on consumers. In the context of this research the Instagram post is seen as advertisement. Therefore, this study defines attitude toward the post as a predisposition to respond in a favorable or unfavorable manner to a particular post.
Different types of sources may lead to differences in attitude toward the post. Currently, no research has been done between sponsored-posts and brand posts on attitude toward the post. However, past research regarding sponsorship found that when consumers viewed a sponsored-post, consumer attitudes toward the post remain unaffected (Lu et al., 2014). The influence of brand posts on attitude toward the post is rather exploratory. Based on logic, it seems reasonable to expect that brand posts lead to a positive brand attitude because brands are more established. Consumers establish close, meaningful relationships with, which involve a collection of perceptions about the brand (Barnes, 2003).
Furthermore, attitude toward the post may have a direct effect on brand attitude. According to Mahcleit and Sahni (1992) attitude toward the ad has an impact on brand attitude. Based on empirical evidence it’s rather a positive impact than negative. Multiple studies found a positive relation between attitude toward the ad and brand attitude
(Goldsmith, Lafferty, & Newell, 2000; Mitchell & Olson, 1981; MacKenzie et al., 1986). However, attitude toward the post may not only have a direct effect on brand attitude but may also explain the relation between type of source and brand attitude. Past research found that attitude toward the ad has a mediating influence on brand attitude (Mitchell and Olson, 1981; Shimp, 1981). Furthermore, research from Goldsmith et al. (2000) found that attitude toward the ad mediates the relation between type of source (corporate vs. endorser)
and brand attitude. Based on the above literature the following hypotheses are proposed:
H2a: A brand post will lead to a more positive attitude toward the post than a sponsored-post by a user.
H2b: Attitude toward the post is positively related to brand attitude.
H2c: Attitude toward the post mediates the relationship between type of source and brand attitude.
Source similarity
Eyal and Rubin (2003, p.80) define source similarity as “the degree in which the recipient of the message corresponds with the qualities, characteristics, and shares values with the source of the message”. Source similarity is based on The Social Identification Theory and the Social Identity Theory. Any source-related characteristic that makes continued association with the source desirable is expected to foster identification (Kelman, 1961). Previous research has highlighted the role of source similarity in this regard. People tend to like similar others, they perceive the attitudes held by similar others as more appropriate to them (Berger, 1977). Additionally, they are more interested in gaining and maintaining acceptance from similar rather than dissimilar others (Campbell & Fairey, 1989).
Furthermore, consumers might recognize themselves into the source of the
advertisement, because they can reflect themselves with a more concrete picture of the person behind the advertising. The degree of source similarity may have positive implications for the evaluation of advertising. Ertimur and Gilly (2012) found that consumers like an
advertisement more when the source is perceived as similar. In addition, a study by Lawrence et al. (2013) showed that participants could identify more with an ad that was made by a consumer than when the ad was developed by a brand.
Furthermore, identification could lead to favorable results for advertisers. For
the consumer who made the ad, the more positive the assessment of the ad was compared to the ad created by a brand. Additionally, in a meta-analysis of the effects of source similarity, Wilson and Sherrell (1993) found that receivers of a message are more likely to adopt opinions when identification occurs.
Next to a direct effect on brand attitude, source similarity may also explain the relation between type of source and brand attitude. According to Berger (1977) people tend to like similar others. When there is a greater perception of source similarity, they perceive the attitudes held by similar others as more appropriate to them. Additionally, in a meta-analysis of the effects of source similarity on persuasion, Wilson and Sherrell (1993) showed that when members of a target audience are more likely to identify with the source, they therefore adopt the opinions of similar others. Based on the above literature, the following hypotheses are stated:
H3a: A sponsored-post by a user will lead to a greater perception of source similarity than a brand post.
H3b: Source similarity is positively related to brand attitude.
H3c: Source similarity mediates the relationship between type of source and brand attitude.
Source credibility
Source credibility refers to “a communicator’s positive characteristics that affect the receiver’s acceptance of a message” (Ohanian, 1990, p.41). The positive characteristics of the source can enhance the value of the message and thus increase acceptance among readers. People are more likely to be persuaded when the source is credible (Hovland, Janis, & Kelley, 1953). Furthermore, trustworthiness and expertise are two factors that underline the concept of source credibility.
According to Ohanian (1990) trustworthiness is “the listener’s degree of confidence in, and level of acceptance of, the speaker and the message” (p.41). Therefore, trust is important for endorsements, it results in the sender of the message being accepted by the receiver (Ohanian, 1990).
Trust might depend on the type of source. The consumers’ intention is usually
believed to have no vested interests in promoting a product and/service of a brand. Therefore, they are considered to be a more trustful source of information than messages that directly derive from brands themselves (Bickart & Schindler, 2001). Additionally, consumers trust peer consumers more than they trust brands (Lee & Koo, 2012). However, when the post is sponsored consumers have a more negative source credibility (Hwang & Jeong, 2016). Sponsored posts typically have a more positive attitude toward the product or service because such posts are motivated by the compensation the user is receiving from the promoted brand (Lu et al., 2014).
The trustworthiness of brands is also questionable because its messages emphasize the positive aspects of products and/or services to improve perceptions and to attract and
encourage customers (Wu & Wang, 2011). Brands’ intention is to influence sales. Therefore, they embed positive statements in brand posts to create a favorable reputation and image. However, Ertimur and Gilly (2012) found that ads created by brands were perceived more credible than consumer ads. Ads created by brands are more influential than consumers ads because those ads are considered to have credible information about the brand while
consumer ads are critiqued as ads (Ertimur & Gilly, 2012)
Furthermore, past studies examine the effects of source credibility on the receiver’s attitude and behavior responses, suggesting that high credible sources produce a more positive attitude and induce more behavioral compliance than sources that are less credible (Ohanian,
1991). Specifically, Chu and Kamal (2008) found that when there is a greater perception of trustworthiness, there would be a greater impact on brand attitude.
Additionally, trustworthiness might explain the relation between type of source and brand attitude. According to Thompson and Malaviya (2013) consumers do not necessarily perceive consumer ads as more trustful than ads created by brands. They found that an advertising message from a consumer could hinder trustworthiness, which lead to a decrease of ad and brand evaluations. Based on the above literature, the following hypotheses are stated:
H4a: A brand post will lead to a greater perception of trustworthiness than a sponsored-post by a user.
H4b: Trustworthiness is positively related to brand attitude.
H4c: Trustworthiness mediates the relationship between type of source and brand attitude.
Expertise
Source expertise refers to “the extent to which a communicator is perceived to be a source of valid assertions” (Ohanian 1990, p.41). That is when the communicator is qualified to provide valid and accurate information or discuss a particular subject. Thus, the expertise of an endorser is present when they are specialized in a specific area of knowledge, or have done enough research to give their opinion on the topic (Scott, 2010).
The communicator’s expertise refers to the level of capability of making correct assertions about the product by possessing relevant skills, competency, and knowledge (Homer & Kahle, 1990). According to Ertimur and Gilly (2012) consumers think that ads created by brands have a greater perception of expertise than consumer ads because
considered to have a greater perception of expertise in their product category than a
sponsored-user who analyzes and reviews products as part of their personal or work interest.
In addition, expertise may have a direct effect on brand attitude. Pornpitakpan (2004) concluded that a source that has a greater perception of expertise leads to positive attitudes towards the source and the advertisement. In addition, recent research found that a greater perception of expertise would lead to a more positive brand attitude (Lim & Chung, 2013; Eisend & Langner, 2010).
Furthermore, a greater perception of expertise may explain the relation between type of source and brand attitude. According to Wang (2006) companies are seen as having more expertise than consumers. Past research also foundthat when individuals perceive the source as an expert, the perceived expertise could increase brand attitude (Amos et al., 2008). Based on the literature above, the following hypotheses are proposed:
H5a: A brand post will lead to a greater perception of expertise than a sponsored-user post by a user.
H5b: Expertise is positively related to brand attitude.
H5c: Expertise mediates the relationship between type of source and brand attitude.
Figure 1. Conceptual model H2a H2b H3a H3b H1 H4a H4b H5a H5b H H2c: H3c: H4c: H5c: Type of source - Brand vs. - Sponsored-user Brand attitude Trustworthiness Expertise Source similarity Attitude toward the post
Type of source - Brand vs. - Sponsored-user
Attitude toward
the post Brand attitude
Type of source - Brand vs. - Sponsored-user
Source similarity Brand attitude
Type of source - Brand vs. - Sponsored-user
Trustworthiness Brand attitude
Type of source - Brand vs. - Sponsored-user
Method Sample
An online experiment was conducted with a convenience sample collected via Facebook, Instagram, LinkedIn, and WhatsApp. The final sample consisted out of 175 participants (28,6% male and 71,4% female) with a mean age of 24.19 years old (SD = 4.77). The majority of the participants were from The Netherlands (64,0%), The United States of America (3,4%), and Poland (2,3%). Furthermore, 45,1% of the participants reported to have a bachelor’s degree, 19,1% a Master’s degree, and 18,9% a high school degree.
Procedure
Participants were provided with a Qualtrics link to enter the online experiment. After giving consent, participants were randomly exposed to a brand post or one of the three sponsored-posts by a user (female, male or neutral). Following the post, multiple scales were used to measure attitude toward the post, source similarity, trustworthiness, expertise, and brand attitude. Subsequently, participants were asked questions tapping into the control variable product involvement. After measuring the control variable, a manipulation check question was asked to test whether the manipulation was successful. Thereafter, questions were asked about their Instagram use. At last, their demographic information was asked including sex, age, nationality, and education. All scales can be found in appendix A. Stimulus
The stimulus materials of this study were Instagram posts presenting a Starbucks coffee. The picture in the Instagram post was the same across all conditions to ensure
consistency and no differences in results due to the picture used. Furthermore, the Instagram post can be either posted by the brand Starbucks or a sponsored-user. The brand condition consisted out of an Instagram post posted by Starbucks without #ad in the caption. However, the sponsored-user condition included #ad in the caption. Additionally, the sponsored-post
was posted by three different hypothetical sources. A male, a female, and a neutral source were chosen for the sponsored-user condition to counterbalance potential gender effects. Furthermore, Starbucks was chosen as the brand, to create a realistic situation that match everyday practices. The Instagram posts can be found in appendix B.
Measurements
Attitude toward the post. The attitude toward the post scale was adapted from Can and Kaya (2016) and consisted of four items. Using a 7-point Likert scale, the four items tapped how much participants (dis) agreed with the statements such as “I like the Instagram
post”, “The Instagram post is nice”, and “The Instagram post appeals to me” (Cronbach’s α
= .93).
Source similarity. The source similarity scale was adapted from Lawrence et al. (2013) and consisted of five items. Participants had to indicate their opinion on a 7-point Likert scale concerning statements such as “The source of the Instagram post is not like
me/like me”, “different from me/similar to me in different ways”, and “The source of the Instagram post and I are similar/different” (Cronbach’s α = .93).
Trustworthiness. The degree of trustworthiness was assessed using five items (Ohanian, 1990). Participants had to indicate their opinion toward the source on a 7-point Likert scale concerning five adjective pairings such as “undependable/dependable”,
“dishonest/honest”, and “unsincere/sincere” (Cronbach’s α = .90).
Expertise. The expertise scale was adapted from Ohanian (1990). Using a 7-point Likert scale, five items such as “inexperienced/experienced”,
“unknowledgeable/knowledgeable”, and “unqualified/qualified” tapped how participants
perceive the source (Cronbach’s α = .91).
Brand attitude. The brand attitude scale was measured with five adjective pairings adapted from Spears and Singh (2004). Participants had to indicate their opinion on a 7-point
Likert scale concerning five adjective pairings like “appealing/unappealing”, “good/bad”, and “likeable/unlikeable” (Cronbach’s α = .96).
Control variable
Product involvement. Product involvement is defined as a person’s perceived relevance of the objects based on the inherent needs, values, and interests (Zaichkowsky, 1985). According to Suh and Yi (2006) relations among brand attitude may vary with involvement. Therefore, product involvement was added as control variable, because participants’ involvement in the product (coffee in this case) may influence participants’ attitude toward the brand. The degree of product involvement was assessed using ten adjective pairings adapted from Zaichkowsky (1994). Participants had to indicate their opinion on a 7-point Likert scale concerning adjectives like “unimportant/important”,
“worthless/valuable”, and “mundane/fascinating” (Cronbach’s α = .97).
Results
Preliminary analysis
Correlations can be found in table 2.
Table 2. Descriptive statistics: mean (M), standard deviation (SD), and correlations (N =
175) M SD 1 2 3 4 5 6 7 8 1. Type of source 1.49 .50 1 2. Source similarity 3.68 1.53 -.13 1 3. Trustworthiness 4.20 1.20 -.08 .51** 1 4. Expertise 4.44 1.33 -.29** .34** .48 1 5. Product 4.45 1.58 -.11 .23** .05 .19* 1 Involvement 6. Attitude toward 4.09 1.60 -.26* .73** .45** .36** -.02 1
the Instagram post
8. Brand attitude 5.12 1.37 -.08 .40** .57** .48** .08 .58** 1
Randomization
A chi-square test showed that randomization was successful and neither gender (2 (1)
= .00, p = .962), nor education (2 (5) =4.92, p = .426), nor nationality (2 (35) =37.03, p = .375) significantly correlated with type of source. An independent t-test showed that age (t (173) = .11, p = .914) and product involvement (t (173) = 1.42 p = .158) were successfully randomized.
Manipulation check
A manipulation check question was asked to indicate whether the difference between a brand post and a sponsored-post was successful. The question was “At the beginning of the
study, you saw an Instagram post. Who was the poster?” Participants could respond with “A brand” and “A user sponsored by a brand”. A chi-square test indicated that the manipulation
of type of source was successful. Results show that type of source was significantly manipulated (2 (1) =49.51 p < .001).
Hypotheses testing
For the main analysis several tests were used to analyze the hypotheses. Analyses of covariance were used to analyze hypothesis 1, 2a, 3a, 4a, and 5a. To test hypothesis 2b, 3b, 4b, and 5b a regression analysis was used. Mediation hypotheses 2c, 3c, 4c, and 5c were analyzed using PROCESS model 4 with 10.000 bootstrap samples (Hayes, 2013). In addition, product involvement was entered as a covariate in all tests.
Hypothesis 1 suggested that a sponsored-post by a user would lead to a more positive brand attitude than a brand post. Analysis of variance indicated that there was no significant effect of type of source on brand attitude (F (1, 172) = .81, p = .370). There was no
statistically significant difference between a brand post (M = 5.25, SD = 1.17) and a sponsored-post (M = 4.83, SD = 1.17). Therefore, hypothesis 1 is not supported.
toward the post than a sponsored-post by a user. Analysis of variance showed that there is a significant effect (F (1, 172) = 9.27, p = .003). A post by a brand (M = 4.58, SD = 1.35) leads to a more positive attitude toward the post than a sponsored-post by a user (M = 3.88, SD = 1.53). Therefore, hypothesis 2a is supported.
Hypothesis 2b stated that attitude toward the post is positively related to brand attitude. A regression analysis showed that there is a significant effect (b = .50, β = .53, p < .001) between attitude toward the post and brand attitude. Attitude toward the post accounted for 27,3% of the variance in brand attitude. Hypothesis 2b is supported.
Hypothesis 2c predicted that attitude toward the post would mediate the relation between type of source and brand attitude. A mediation analysis using PROCESS showed that the indirect effect of type of source on brand attitude through attitude toward the post was significant (point estimate = -.1931; 95% CI = -.4350 to -.0576). Hypothesis 2c was supported.
Hypothesis 3a suggested that a sponsored-post by a user would lead to a greater perception of source similarity than a brand post. Analysis of variance showed that there was no significant effect of type of source on source similarity (F (1,172) = 2.09, p = .150). There was no statistically significant difference between a brand post (M = 3.87, SD = 1.46) and a sponsored-post (M = 3.48, SD = 1.57). Hypothesis 3a is not supported.
Hypothesis 3b stated that source similarity is positively related to brand attitude. A regression analysis showed that there is a significant effect (b = .36, β = .40, p < .001) between source similarity and brand attitude. Source similarity accounted for 15,0% of the variance in brand attitude. Hypothesis 3b is supported.
Hypothesis 3c suggested that source similarity would mediate the relation between type of source and brand attitude. PROCESS showed that the indirect effect of type of source on brand attitude through source similarity was not significant (point estimate = .0048; 95%
CI = -.0490 to .0974). Hypothesis 3c is not supported.
Hypothesis 4a predicted that a brand post would lead to a greater perception of trustworthiness than a sponsored-post by a user. Analysis of variance showed there is no significant effect of type of source on trustworthiness (F (1,172) = .95, p = .332). There was no statistically significant difference between a brand post (M = 4.30, SD = 1.18) and a sponsored-post (M = 4.11, SD = 1.22). Hypothesis 4a is not supported.
Hypothesis 4b stated trustworthiness is positively related to brand attitude. A regression analysis showed that there is a significant effect (b = .65, β = .57, p < .001) between source similarity and brand attitude. Trustworthiness accounted for 31,8% of the variance in brand attitude. Hypothesis 4b is supported.
Hypothesis 4c predicted that trustworthiness would mediate the relation between type of source and brand attitude. PROCESS showed that the indirect effect of type of source on brand attitude through trustworthiness was not significant (point estimate = -.0687; 95% CI = -.2371 to .0587). Hypothesis 4c is not supported.
Hypothesis 5a suggested that a brand post would lead to a greater perception of expertise than a sponsored-post by a user. Analysis of variance indicated that there is a significant effect of type of source on expertise (F (1,172) = 14.21, p < .001). A post by a brand (M = 4.83, SD = 1.28) leads to a greater perception expertise than a sponsored-post by a user (M = 4.06, SD = 1.27). Hypothesis 5a is supported
Hypothesis 5b stated that expertise is positively related to brand attitude. A regression analysis showed that there is a significant effect (b = .49, β = .48, p < .001) between expertise and brand attitude. Expertise accounted for 21,7% of the variance in brand attitude.
Hypothesis 5b is supported.
Hypothesis 5c suggested that expertise would mediate the relation between type of source and brand attitude. PROCESS indicated that the indirect effect of type of source on
brand attitude through expertise was significant (point estimate = .1552; 95% CI = .3404 to -.0349). Hypothesis 5c is supported.
The conceptual model in figure 2 illustrates a summary of the results.
Figure 2 Conceptual model Results Significant Not significant H2a H2b H3a H3b H1 H4a H4b H5a H5b H H2c: Type of source - Brand vs. - Sponsored-user Brand attitude Trustworthiness Expertise Source similarity Attitude toward the post
Type of source - Brand vs. - Sponsored-user
Attitude toward
H3c:
H4c:
H5c:
Discussion
Academic research dedicated to Instagram is limited (Djafarova & Rushworth, 2017; Sheldon & Bryant, 2016; Pittman & Reich, 2016). This study provides further understanding of its usage. Specifically, this research aimed to investigate source effects (brand vs.
sponsored-user) on brand attitude and the mediating roles of attitude toward the post, source similarity, trustworthiness, and expertise within the Instagram platform.
Findings show that type of source is linked to brand attitude through attitude toward the post. A brand post leads to a more positive attitude toward the post, which is positively related to brand attitude. This result is consistent with past research that found that attitude toward the ad plays a mediating role (Mitchell & Olson, 1981). A possible explanation for current finding could be that the brand is already established in consumers’ mind. According to Barnes (2003) consumers do establish close and meaningful relations with brands.
Starbucks is a well-known brand, which may already established a meaningful relation with consumers. For this reason, consumers may already have created positive attitudes toward the brand.
Type of source - Brand vs. - Sponsored-user
Source similarity Brand attitude
Type of source - Brand vs. - Sponsored-user
Trustworthiness Brand attitude
Type of source - Brand vs. - Sponsored-user
In addition, both the previous literature on expertise and current research show that expertise plays a mediating role. Amos et al. (2008) found that expertise could increase brand attitude, when individuals perceive the source as an expert. Current findings show that type of source has an indirect effect on brand attitude through expertise. A brand post leads to a greater perception of expertise, which is positively related to brand attitude. A possible explanation for this finding could lie in the consumers’ prior expectation of an expert. Based on logic, a brand is considered to have a higher expertise in their product category than a sponsored-user who analyzes and reviews products as part of their personal or work interest. Additionally, past research found that consumer ads could decrease brand evaluations because common users are seen as less competent than brand experts (Thompson & Malaviya, 2013).
Furthermore, this study found that source similarity is positively related to brand attitude. This is in line with research from Thompson and Malaviya (2013) who found that when there is a greater perception of source similarity, the greater the evaluation of the ad. However, source similarity does not mediate the relationship between type of source and brand attitude. This result is not in line with research from Wilson and Sherrell (1993) who showed that when consumers are more likely to identify with the source, they therefore adopt others opinions. Furthermore, there was no direct effect found for type of source on source similarity. This is not in line with past research from Lawrence et al. (2013) who found that consumers feel more similar to other consumers than a brand. However, Lawrence et al. (2013) investigated commercials, which are different type of advertising than Instagram posts. For this reason, advertising type could explain why type of source does not influence source similarity, which therefore does not mediate the relation between type of source and brand attitude.
In addition, findings show that trustworthiness is positively related to brand attitude. This is in line with research from Chu and Kamal (2008) who found that when there is greater
perception of trustworthiness, there would be a greater impact on brand attitude. However, trustworthiness does not play a mediating role between type of source and brand attitude. A possible explanation could lie in the consumers’ prior expectation of trust. Both a brand’s and a sponsored-user’s trust is questionable. They both show positive aspects of products to improve perceptions and to attract and encourage customers (Wu & Wang, 2011; Lu et al, 2014).
At last, there was no significant direct effect found between type of source and brand attitude. This is contradicting to past research, which found that consumers did not seem to care if a consumer-generated advertising is created for personal gain. They were only interested in that the ad came from a consumer instead of a brand (Thompson & Malivaya, 2013). A possible explanation could lie in consumers’ brand loyalty. According to Oliver (2014) loyalty is “a deeply held commitment to rebuy or indulge a preferred product and/or service consistently in the future, despite situational influences and marketing efforts having the potential to cause switching behavior” (p.392). Starbucks is a well-known brand and consumers may feel loyal toward this brand. Therefore, it is possible that consumers are not influenced by the type of source on their attitude toward the brand.
Implications
Based on the findings, this research makes several theoretical and practical
contributions to the field of online marketing communication. Previous research examining sponsored-posts in comparison with brand posts is limited. However, this research submits findings to understand the effectiveness of brand posts versus sponsored-post on brand attitude and the underlying mechanisms attitude toward the post, source similarity,
trustworthiness, and expertise on the social media platform Instagram. In addition, this study indicates that Instagram posts with different profiles differ on brand attitude and therefore
highlights the importance of research on source effects to determine the most effective way to advertise brands, products and/or services on Instagram.
Furthermore, advertisement is a significant way for businesses to market their
products. Marketers improve recognition and create demand for their products by advertising. It was understood through this study that advertisements on Instagram have an impact on brand attitude. Based on findings, brands posts are more effective than sponsored-posts to create a positive brand attitude. Therefore, this research is of high importance for practitioners because it provides suggestions for effective and low-cost Instagram advertising strategies.
Limitations and suggestions for future research
Current research is one of the first studies that focus on source effects on Instagram. Therefore, this research has several limitations. The most important limitation of this research is the use of one familiar brand (Starbucks). Familiar brands enjoy higher levels of liking among both consumers and retailers (Colombo & Morrison, 1989). Consumers may have tried or used a familiar brand or may have family or friends who have used the brand. In contrast to unfamiliar brands, consumers lack many associations because they have not had any
experiences with them (Campbell & Keller, 2003). All in all, familiar brands may have an advantage from being better liked than less familiar brands (Colombo and Morrison, 1989). Therefore, future research should include a broader spectrum of brands.
Furthermore, a convenience sampling is used to obtain the sample of this study. Thus, individuals between 18-30 years old comprise most of the respondents. A different age group might lead to different results. In addition, according to de Mooij and Hofstede (2010) different advertising strategies are needed for different cultures. However, this study used a more European/Dutch sampling, which could be problematic in terms of generalization. Therefore, future studies should focus on random sampling and engaging in cross-cultural comparisons to extend the generalizability of the results.
Furthermore, future research could expand the model by focusing on different variables such as purchase intention. According to Fishbein and Ajzen (1975) consumer attitudes directly affect their purchase behavior. Therefore, it might be interesting to ad purchase intention to the research model. In addition, it is interesting for future research to investigate a broader spectrum of high and low involvement products. This study focused only on coffee, which is a low involvement product. For low involvement products, peripheral cues are more important than issue-relevant arguments. However, for high involvement products the opposite is true. The level of product involvement has been recognized as an important factor affecting a consumer’s response to marketing messages (Danaher & Mullarkey, 2003; Petty et al., 1983). Therefore, future research may find different results when using high and low involvement products.
Conclusion
This study investigated source effects (brand vs. sponsored-user) on brand attitude and the mediating roles of attitude toward the post, source similarity, trustworthiness, and
expertise. Results show that attitude toward the post mediates the relationship between type of source and brand attitude. A brand post leads to a more positive brand attitude than a
sponsored-post, which in turn is positively related to brand attitude. Furthermore, also expertise acts as a mechanism between type of source and brand attitude. A brand post leads to a greater perception of expertise than a sponsored-post, which in turn is positively related to brand attitude. Additionally, a greater perception of source similarity and trustworthiness is positively related to brand attitude. Based on these findings, this study contributes to the field of online marketing communication. Marketers are constantly searching for new ways to improve recognition and create demand for their products. One of these new ways is to sponsor Instagram users in order to promote their products and/or services. However, this study found that brand posts are more effective than sponsored-posts to create a positive
brand attitude. Therefore, brands should consider investing in new ways to create authentic posts themselves. All in all, this study provides practitioners suggestions for effective and low-cost Instagram advertising strategies.
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Appendix A
Attitude toward the Instagram post Can and Kaya (2016)
Please respond to each of the following statements about the Instagram post you just saw.
Strongly disagree 1 2 3 4 5 6 7 Strongly agree
1. I like the Instagram post.
2. I am interested in the Instagram post. 3. The Instagram post appeals to me. 4. The Instagram post is nice.
Source similarity Lawrence et al. (2013)
1. The source of the Instagram post is… Not like me 1 2 3 4 5 6 7 Like me
Different from me 1 2 3 4 5 6 7 Similar to me in many ways 2. The source of the Instagram post has
Not same beliefs/values as me 1 2 3 4 5 6 7 Same beliefs values as me 3. The source of the Instagram post feels
Not related to me 1 2 3 4 5 6 7 Related to me 4. The source of the Instagram post and I are Different 1 2 3 4 5 6 7 Similar
Trustworthiness Ohanian (1990)
Please describe your overall feeling about the Instagram poster (source of the Instagram post) you just saw:
Dependable 1 2 3 4 5 6 7 Undependable Honest 1 2 3 4 5 6 7 Dishonest Reliable 1 2 3 4 5 6 7 Unreliable Sincere 1 2 3 4 5 6 7 Insincere Trustworthy 1 2 3 4 5 6 7 Untrustworthy Expertise Ohanian (1990)
Please describe your overall feeling about the Instagram poster (source of the Instagram post) you just saw:
Expert 1 2 3 4 5 6 7 Not an expert Experienced 1 2 3 4 5 6 7 Inexperienced
Knowledgeable 1 2 3 4 5 6 7 Unknowledgeable Qualified 1 2 3 4 5 6 7 Unqualified
Brand attitude
Spears & Singh (2004)
Please describe your overall feeling about the brand in the Instagram post you just saw: Appealing 1 2 3 4 5 6 7 Unappealing Good 1 2 3 4 5 6 7 Bad Pleasant 1 2 3 4 5 6 7 Unpleasant Favorable 1 2 3 4 5 6 7 Unfavorable Likable 1 2 3 4 5 6 7 Unlikable Product involvement Zaichkowsky (1994)
Please describe your overall feelings about coffee in general: 1. Important 1 2 3 4 5 6 7 Unimportant
2. Boring 1 2 3 4 5 6 7 Interesting 3. Relevant 1 2 3 4 5 6 7 Irrelevant 4. Exciting 1 2 3 4 5 6 7 Unexciting
5. Means nothing 1 2 3 4 5 6 7 Means a lot 6. Appealing 1 2 3 4 5 6 7 Unappealing 7. Fascinating 1 2 3 4 5 6 7 Mundane 8. Worthless 1 2 3 4 5 6 7 Valuable 9. Involving 1 2 3 4 5 6 7 Uninvolving 10. Not needed 1 2 3 4 5 6 7 Needed
Manipulation check
At the beginning of the study, you saw an Instagram post. Who was the poster? - A brand
Appendix B
