The Antecedents and Consequences of Consumption-Related Posting Behavior on Social Media

Posting consumption items on social media has become a common consumer behavior. It represents a new type of word-of-mouth activity. This dissertation investigates the factors that contribute to consumption-related posting behavior (CPB) on social media and the influences of such behavior on how consumers enjoy their purchases. It offers evidence from six studies in support of a framework incorporating the antecedents and consequences of CPB on social media. Antecedents – intrinsic enjoyment of using social media, the motivation to express oneself through word-ofmouth and purchase type – positively predict the posting behavior. Experiential purchases are more likely to be posted than material purchases. Materialism, however, moderates the effects of purchase type on posting. Specifically, lower-materialism consumers are more likely to post experiential purchases than material purchases, while higher-materialism consumers tend to post both types of purchases. For the consequences of CPB on social media, materialism is found to be a moderator interacting with CPB on social media to influence consumers’ enjoyment with their purchases. CPB on social media leads lower-materialism consumers to enjoy their purchases more; on the other hand, CPB on social media does not have such effects on higher-materialism consumers. Moreover, CPB on social media influences enjoyment with purchase through the purchase’s impact on self and interpersonal relationship. This dissertation makes significant contributions to the research on word-of-mouth, social media as well as materialism. It provides important managerial implications as well.


CHAPTER 1: INTRODUCTION
As of January 2016, there were 1.59 billion monthly active Facebook users (Smith, 2016): one in every seven persons on Earth is a Facebook user. Along with Facebook, social media in other formats, have been rapidly growing as well. For instance, Twitter now has 500 million visitors every month (Lambert, 2016); Instagram has more than 400 million active users (Kharpal, 2015) and more than 48,500 photos are posted on it every minute (Kapko, 2015); pins have been increasing more than 75% annually on Pinterest (Claveria, 2015). Mobile access has expanded the reach of social media with 12 new active mobile social media users added every second, equaling to 1 million every day (Regan, 2015). All these statistics suggest that social media have become an integral part of our daily life. Our interpersonal relationships, the ways we interact with others and conduct business, our concept of privacy and even the definition of "friend", have been transformed by social media in the short span of only a decade (Elgot, 2015).
Behaviors of consumers are also being influenced greatly by social media. Huttom (2012) pointed out that social media have transformed users from passive to active consumers who create content about products and consumption experiences. For instance, there have been more than 22 million pictures about Nike and over 9 million pictures about Starbucks posted by consumers on Instagram (O'Connor, 2015). In fact, user-generated content about brands is increasingly dominating the Internet. In the search results for the world's 20 largest brands, 25% represent user-generated content (Smith, 2015).
Indeed, many consumers nowadays routinely generate their own content about brands by posting consumption items on their favorite social media sites. For instance, a traveler shares pictures of trips she enjoys to her Instagram followers; a food lover updates his Twitter about experiences with various restaurants; a home decoration enthusiast pins her favorite decoration designs on her Pinterest board. As Figure 1.1 demonstrates, consumption-related posting behavior (CPB) on social media can be defined as a behavior that enables consumers to communicate feelings and/or thoughts about their own purchases or interested consumption items to their social media audience. CPB on social media may be driven by the motivation to express oneself, attract attention as well as to interact with others or to show off wealth / social status.
To the best of my knowledge, no prior research has explored CPB on social media.

Figure 1.1: Examples of Consumption-Related Postings
It is critical to understand CPB on social media because it has become a worldwide phenomenon. As the statistics shown earlier in this chapter suggest, social media users are growing rapidly around the world and increasingly use mobile devices to access social media. Mobile access allows people to capture, record and communicate consumption activities much easier on social media, which contributes to the popularization of CPB on social media around the world. Also, CPB on social media creates user-generated content about brands, which provide important insights for marketers about their customers.
CPB on social media is a type of word-of-mouth (WOM), which is defined as oral, informal, person-to-person communicationbetween a perceived noncommercial storyteller and a receiverregarding a brand, a product, an organization, or a service (Higie, Feick, and Price, 1987). CPB on social media, however, has characteristics distinct from traditional word-of-mouth (WOM). For example, immediacy of social media enables consumers to share information at times and places that are most convenient for them (Sun, Youn, Wu, and Kuntaraporn, 2006), therefore it is easier for the storyteller to transmit WOM messages by CPB on social media. Because the asynchronous and broadcasting characteristics of social media enable a wider reach and encourage self-presentation (Barasch and Berger, 2014;Walther, 2011), consumers may be more willing to share thoughts or feelings about consumption items via CPB on social media. Broadcasting also leads to high visibilityprivately-used products and experiential purchases now can be visible to a wide range of audience. As a result, when engaging in CPB on social media, consumers can use a greater assortment of consumption itemsmaterial and experiential, publicly-and privately-used onesto enhance their self-images or improve their status. Therefore, CPB on social media can be associated with conspicuous meanings. Because of these characteristics, CPB on social media is different than traditional WOM. Thus, we can say that CPB on social media is a new type of WOM behavior that needs systematic research investigation.
Previous research on antecedents of WOM has discovered several motivations that drive WOM, such as impression management, identity expression, social bonding and so on (Berger, 2014), but CPB as a new form of WOM, may be motivated by more or different factors besides those known ones. Moreover, past research on the consequences of WOM mostly focused on WOM receivers, revealing that WOM has powerful influences on receivers' information search, evaluation and decision making (e.g. Brown and Reingen, 1987). In contrast, the consequences of WOM on the storytellers themselves are under explored.
Recognizing these research gaps, my dissertation investigates why CPB on social media happens and how it influences the storyteller. Based on a thorough literature review of WOM, materialism, intrinsic motivation of using social media and purchase type, I propose a framework that captures the antecedents and consequences of CPB on social media. Specifically, intrinsic enjoyment of using social media, motivation to express oneself and attract attention via WOM and purchase type are proposed as antecedents of CPB on social media. Experiential purchases are more likely to be posted than material ones. Materialism, an important consumer value that affects how consumers view their possessions (Belk, 1985), is expected to moderate the effect of purchase type of CPB on social media.
Regarding the consequences of CPB on the storyteller, I am interested in enjoyment with consumption items, including satisfaction, positive consumption emotions (joy and excitement), as well as happiness. I posit that materialism also moderates the effects of CPB on enjoyment with purchase. Moreover, I propose that the impact of purchase on self and interpersonal relationship serve as mediators between CPB on social media and enjoyment with the purchase. The results support the hypothesis that lower-materialism consumers are more likely to post experiential purchases than material purchases, whereas higher-materialism consumers are likely to post both types of purchases.
The consequences were also tested in multiple studies. Convergent results from Finally, as mentioned above, CPB on social media creates user-generated content that is beyond marketers' control. Understanding the behavior has important managerial implications for marketing in the social media era. The research and managerial implications of this dissertation will be elaborated upon in greater detail in the conclusions chapter. The limitations of this dissertation research and future research directions will also be discussed in the conclusions chapter.

CHAPTER 2: THEORITICAL BACKGROUND
The chapter first reviews prior research on WOM including recent research on social media WOM, because CPB on social media is a new type of WOM. Next, previous research on materialism, intrinsic motivation of using social media, and purchase type are reviewed as they may explain why CPB on social media happens.
Finally, the chapter reviews research on enjoyment with purchase including consumption emotions, post-purchase satisfaction and happiness, which are the consequences of CPB on the storyteller. Does not mention impact on self and interpersonal? Research gaps are identified following each section of the review and also summarized at the end of this chapter.

Traditional WOM
Word-of-mouth (WOM) is defined as oral, informal, person-to-person communication between a perceived noncommercial story teller and a receiver regarding a brand, a product, an organization, or a service (Higie, et al., 1987). Therefore, WOM is a consumer-dominated channel where the storyteller does not represent any product manufacturer or service provider. It contains information about product performance and the social and psychological consequences of the purchase decision (Cox, 1963). It is thus perceived to be more reliable, credible, and trustworthy by consumers compared to communication and advertisements from companies (Brown, Broderick and Lee, 2007;Sternthal, Dholakia and Leavitt, 1978).
Research has confirmed that WOM has a powerful influence on the receiver, especially on information search, evaluation, and decision making (Cox, 1963;Brown and Reingen, 1987;Money, Gilly and Graham, 1998;Silverman, 2001). WOM can convert lower order cognition and affect into higher order cognition and affect, subsequently leading to committed behaviors (Bristor, 1990). Through multiple exchanges, one WOM message can reach and potentially influence many receivers (Lau and Ng, 2001). Whether a WOM receiver has previous interactions with a product or brand (Bone, 1995;Herr, Kardes and Kim, 1991) and whether the message is congruent with the receiver's current knowledge (Laczniak, DeCarlo and Ramaswami, 2001) also affect the influences of WOM on the receiver.
What motivates WOM is an important topic that has attracted considerable research attention. Advice seeking and persuading others are perhaps the most apparent and common reasons that drive WOM behaviors (Brown and Reingen, 1987).
Consumers engage in WOM to also manage others' impression towards them. We are fundamentally motivated to enhance ourselves (Fiske, 2001), so we present ourselves in particular ways to gain desired impressions in social interactions (Goffman, 1959).
Research has found that consumers are more likely to share things that make them look good rather than bad (Chung and Darke, 2006;Hennig-Thurau et al., 2004;Sundaram, Mitra and Webster, 1998) and improve status (Engel, Blackwell and Miniard, 1993;Rimé, 2009).
Besides enhancing themselves, consumers also use WOM to communicate specific identities, including certain characteristics, knowledge, or expertise in a particular domain (Chung and Darke, 2006;Packard and Wooten, 2013), both to themselves and others. Numerous research studies suggest that consumption and possessions are used by consumers to express their uniqueness or their group identity (e.g., Berger and Heath 2007). Products consumed in public, where they can be seen by others, are of greater importance for identity communication (Childers and Rao, 1992).
Knowledge and expertise are important elements of one's identity. Consumers that have (or desire) expertise in a given area may be particularly interested in displaying it to others. Market mavens, or those with general marketplace knowledge or expertise, are likely to share product information with others (Higie et al., 1987;Sternthal, et al., 1978).
Another motivation that drives word of mouth is to connect with others (Rimé, 2009). Because purchases signal identities and communicate self-concepts to others, talking about purchases allows consumers to connect with similar others (Berger and Heath, 2007;DiMaggio, 1987;Douglas and Isherwood, 1978). Talking to a friend about a product you both like or an activity you are both interested in reinforces that you have things in common (Berger, 2014). Talking about popular advertisements, for example, gives teenagers common ground and a kind of social currency that allows them to connect with their peers (Ritson and Elliott, 1999). Emotion towards purchases expressed in WOM also connects the storyteller and the receiver, as emotion-sharing bonds people together (Peters and Kashima, 2007). Recent research confirms that feeling high arousal emotions may increase social bonding needs (Chan and Berger, 2013).
Additionally, consumers also use WOM to deal with negative consumption experiences. It is very common that angry consumers (Wetzer, Zeelenberg and Pieters, 2007) or dissatisfied customers (Anderson, 1998) disseminate WOM to vent, or to punish a company or individual (Ward and Ostrom, 2006).
Compared to the motivations of WOM, there are far fewer studies which have explored the consequences of WOM on the storyteller, or how the medium of WOM influences the behavior. A few research studies suggest that WOM allows people to rehearse and relive positive emotional experiences (Hennig-Thurau et al., 2004;Rimé, 2009). Talking about positive purchases makes people happier (Bastos, 2013). A recent research demonstrates that the medium of WOM can shape the content of WOM: written WOM leads people to mention more interesting products and brands (Berger and Iyengar, 2013).

Consumption-Focused Self-Expression Word of Mouth (CSWOM)
A recent research study conducted by Saenger, Thomas and Johnson (2013) identifies another motivation to spread word of mouthexpressing oneself and attracting attention to oneself. Their research is the first to define such motivation as consumption-focused self-expression word of mouth (CSWOM). CSWOM is distinct from other word-of-mouth motivations that have been discussed above. Consumers with CSWOM motivation do not necessarily desire to influence others' purchase behaviors or help them make purchase decisions; instead, they simply inform others of their purchases (Saenger, et al., 2013). Consumers who are motivated by CSWOM do not aim to be seen as more expert or more innovative than other consumers; they are simply seeking attention and express who they are (Saenger, et al., 2013). In addition, when consumers motivated by CSWOM discuss brands that they are loyal to, they are communicating their self-concept and attracting attention rather than helping the brand (Saenger, et al., 2013). Therefore, people with stronger CSWOM motivation talk about their purchases to make others know them better, and they enjoy the attention others pay to them during the process. Saenger, et al. (2013) have developed a scale to measure CSWOM.
CSWOM is very relevant to CPB on social media, because it seems that such posting behavior is about self-expression and attracting attention. The construct of CSWOM has been used in different contexts. For example, Ruane and Wallace (2015) find that CSWOM is related to loyalty to online brand tribes; Sudbury-Riley (2016) reveals that market mavens among the baby boomer generation in the United Kingdom are motivated by CSWOM to distribute marketplace information.

WOM on Social Media
WOM on social media entails communicating about brands, products or services via social media platforms. Because WOM on social media is a new type of WOM, the antecedents of traditional WOM reviewed abovesuch as impression management, identity expression or interpersonal connectionmay also contribute to WOM on social media. WOM on social media, however, has characteristics different from traditional WOM.
First, unlike traditional WOM, social media offers immediacy (Kaplan and Haenlein, 2010). It enable consumers to engage in WOM at times and places that are most convenient for them (Sun, et al., 2006), thereby making consumers feel more comfortable and flexible about sharing their experiences and opinions. As selfdisclosure is intrinsically rewarding (Tamir and Mitchell, 2012), the comfort and flexibility that social media offer should encourage more sharing about one's own purchases. Indeed, over 70% of social media posts are about the self or one's own immediate experiences (Naaman, Boase and Lai, 2010). Mobile access to social media further increases immediacy of self-expression (Kaplan, 2012).
Second, compared to traditional WOM which is synchronous, WOM on social media is more asynchronous, where people may respond hours or even days later. This asynchrony allows people to engage in greater selective self-presentation (Walther, 2011), such as being more polite during the interaction (Duthler, 2006 Sometimes when we need social support, we may be reluctant to reach out to specific others because we do not want to bother people or do not want to appear needy and may worry about being rejected. In such situations, undirected communication may be particularly useful because it lets people have the opportunity for social connection and support without such risk. For instance, when seeking advice on a certain product category, WOM on social media allows people to cast a wide net rather than having to target one person in particular, thus simultaneously decreasing the weight put on any one tie and increasing the number of potential responses or advice bits that one can receive, increasing perceived social support . Fifth, compared to traditional WOM which is oral communication, WOM on social media is written communication. Past research suggests that written communication leads people to bring up more interesting products and brands (Berger and Iyengar, 2013). The asynchrony of written communication gives people more time to construct and polish what to say. Self-enhancement concerns lead people to use this opportunity to talk about more interesting products and brands.
In addition, social media offer anonymity which reduces social acceptance concerns (Berger, 2014). Because most social media are open to an audience larger than close social ties, WOM audience on social media can be unidentifiable. This may increase the social risk associated with persuading others (Mandel, 2003). Also, compared to face-to-face WOM which allows customization of the message to the targeted audience, the variable nature of the ties also makes tailoring the message to various audiences nested within the network quite complicated (Leary, 1990;Leonhardt, Keller, and Pechmann, 2011). All these disadvantages, however, may be attenuated by anonymity.
Furthermore, whereas traditional WOM usually takes place via one-to-one or one-to-few oral communication, WOM on social media is broadcasted to an individual's social network containing a much larger audience. This is a different distinction than the directed vs. undirected communication, which is concerned with targets of audience rather than audience size. For example, broadcasting can be directed if the message is sent to a specific large size of audience. Compared to narrowcasting, broadcasting impacts the transmission process by shifting sharer focus (Barasch and Berger, 2014).
People have a natural tendency to focus on themselves. Narrowcasting, however, encourages "other" focus because communicating with one person promotes individuation, leading people to self-present less and share more content that is useful to the message recipient (Barasch and Berger, 2014). Broadcasting, on the other hand, does little to move people away from their natural tendency to self-focus and, as a result, encourages stronger self-presentation (Barasch and Berger, 2014) as well as boosts more status seeking concerns (Lampel and Bhalla, 2007).
Broadcasting not only encourages but also facilitates status seeking, as it extends conspicuous consumption beyond publicly visible consumption items. Conspicuous consumption is essentially an instrument of signaling: possessions and behaviors can act as signals of identity, sexual or social, to others (Berger and Heath 2007;Holt, 1998;Wernerfelt 1990). The more a consumer seeks status, the more he/she will engage in conspicuous consumption (Eastman, Ronald and Flynn, 1999). Privately-used products, which were hard to display publicly in the past, generally could not serve for purposes of conspicuous consumption. Likewise, experiential purchases such as travel were also hard to display publicly beyond close interpersonal communication. With social media, however, both privately-used products and experiential purchasessuch as an expensive mattress, meaningful personal notes, high-end skin-care products, or a luxury can be broadcasted readily to a larger audience, affording public visibility to previously private consumption. As a result, social media enable consumers to use a much larger assortment of consumption items to signal self-concept and to compete with each other.
Eighth, social media is interactive. Interactivity is defined in terms of the degree to which a communication system can allow one or more end users to communicate alternatively as senders or receivers (Fortin and Dholakia, 2005

Materialism
Prior research reveals that conspicuous consumption is positively related to materialism (e.g., Podoshen and Andrzejewksi, 2012). Materialism is defined as the tendency to view acquisitions as the necessary means to reach important life goals and desired end states (Richins and Dawson, 1992). Higher-materialism consumers place more importance on acquisition and ownership of possessions than lower-materialism consumers (Belk, 1985). Materialism has three important components: centrality of acquisition and possessions in one's life, the tendency to judge personal success on the basis of acquisitions, and the belief that one's happiness depends on acquisitions (Richins and Dawson, 1992).
Centering one's life on acquisitions and possessions means that acquiring and owning material possessions generates high gratification for higher-materialism consumers (Pieters, 2013). They tend to derive pleasure from the process of buying things, feel the joy of spending money on things that are not necessarily practical, and like a lot of luxury in life (Richins and Dawson, 1992). They are likely to have stronger desire for unique consumer products (Lynn and Harris, 1997), seek luxury products (Eastman et. al, 1999;Roberts, 2000), and spend more time on shopping and acquiring (Fitzmaurice and Comegys, 2006).
Defining personal success based on possessions entails a social comparison between oneself and others using material possessions. Consumers with materialistic values are more likely to use material objects they own as a sign of their success, desire to own possessions that impress others, and admire people who own expensive possessions (Richins and Dawson, 1992). Indeed, studies consistently show that highermaterialism consumers are more likely to use material products to communicate information about themselves to others, such as signaling status or identity (Sundie et al., 2011). For higher-materialism consumers, the acquisition and possession of material goods is essential to their self-definition (Richins, Mick, and Monroe, 2004), and identity construction (Shrum et al., 2013).
Pursuing happiness through acquisition rather than through other means (such as personal relationships, experiences, or achievements) is another important characteristic of materialism (Richins and Dawson, 1992). Higher-materialism consumers often compare their present state with a better future state, with more or nicer possessions. Their mindset reflects an insufficiency or dissatisfaction with the present (Pieters, 2013). Higher-materialism consumers feel they do not have all the things they need to enjoy life, are bothered by not being able to buy things they like, and anticipate improved happiness if they could own more or nicer things (Richins and Dawson, 1992).
Furthermore, higher-materialism consumers are more oriented toward extrinsic goals such as financial success, image, and status (Kasser andRyan 1993, 1996). As a result, they feel less autonomous and more externally controlled, which is associated with various negative wellbeing and relationship implications (Carver and Baird, 1998;Deci and Ryan, 2000;Ryan and Deci, 2000). In addition, they typically invest fewer resources in activities that are related to intrinsic goal pursuits, such as self-actualization or investment on relationships with others, which have been shown to be more beneficial to one's subjective wellbeing than the pursuit of extrinsic goals (Kasser and Ryan, 1993;Richins, 1987;Ryan and Deci, 2000). They are more likely to compete than cooperate with their friends (Sheldon, Sheldon and Osbaldiston, 2000), and their connections with others tend to be shorter and less satisfying (Kasser and Ryan, 2001).
In contrast, the motivational systems of lower-materialism people are concerned with expression of interest, enjoyment and doing things for their own sake (Kasser, 2002). Unlike higher-materialism consumers, lower-materialism consumers do not consider the acquisition of goods as a path to personal happiness (Ahuvia and Wong, 2002;Fournier and Richins, 1991). They place more importance on interpersonal relationships (Kasser and Ryan, 1993;Richins and Dawson, 1992;Schwartz, 1996).
Such distinctions result in striking differences between the values lower-and higher-materialism consumers obtain from their possessions and what they hope to receive from possessions they wish to acquire (Richins 1994). Lower-materialism consumers value the personal enjoyment of using a product, the personal spiritual benefits associated with the product or the sentimental meanings associated with the possessions that remind them of people important in their lives (Richins 1994). Highermaterialism consumers, however, are more likely to value objects because of their financial value, their attractive appearance, or their ability to improve the status or looks of their owners (Richins 1994). These values are associated with public meanings and depend on the reactions of others. The most widely used scale to measure materialism is Richins '(2004) Material Values Scales (MVS).
Consumer researchers have investigated the relationship between materialism and various psychological and economic constructs. Materialism is negatively related with consumer wellbeing (Burroughs and Rindfleisch, 2002), and is responsible for risky consumption behaviors such as compulsive buying (Dittmar, 2005;Rindfleisch, Burroughs and Denton, 1997;Roberts, 2000), smoking (Williams et al., 2000) and substance abuse (Vansteenkiste, Lens and Deci, 2006). Richins (2013) finds that highermaterialism consumers experience both stronger positive and negative consumption emotions than lower-materialism consumers, but their positive consumption emotions fade quickly after purchase.
The review above suggests multiple gaps in the existing research on materialism.
Materialism has not been examined in the social media context or been linked with WOM or CPB on social media. Research on how materialism influences enjoyment with purchases is quite limited.

Intrinsic Motivation of Using Social Media
Self-Determination Theory (SDT; Deci and Ryan, 1985) maintains that the type or quality of a person's motivation would be more important than the level of motivation for influencing outcomes. It distinguishes whether people act because the act itself is inherently interesting or enjoyable, or because the act leads to a separable outcomethe distinction between intrinsic or extrinsic motivations. Intrinsically motivated behavior, which is driven by people's interest in the activity itself, is prototypically autonomous (Deci and Ryan, 1985). Externally motivated behavior, which is initiated and maintained by contingencies external to the person, is the classic type of controlled motivation (Deci and Ryan, 1985).
Research has identified the intrinsic value associated with social media and online community. Dholakia, Bagozzi and Pearo (2004) and Nambisan and Baron (2007) show that entertainment value is one of the motivations of engaging in virtual communities. Kunz, Munzel and Jahn (2012) show that intrinsic fun stimulates involvement in online review sites. Nov, Naaman and Ye (2010) demonstrate that intrinsic enjoyment contributes to participation in online photo-sharing communities.
Okazaki (2009) (2011) identify enjoyment as an intrinsic benefit contributing to social media usage.
How intrinsic enjoyment of using social media impacts CPB on social media has not been investigated.

Purchase Type
CPB on social media can make both material and experiential consumption items publicly visible. Past research suggests that people enjoy experiential purchases more than material purchases (e.g., Carter and Gilovich, 2011;Van Boven and Gilovich, 2003). Experiential purchases are defined as those "made with the primary intention of acquiring a life experience: an event or series of events that one lives through," while material purchases are defined as those "made with the primary intention of acquiring a material good: a tangible object that is kept in one's possession" Gilovich 2003, p. 1194).
People tend to construct and define themselves more in terms of their life experiences than their material possessions. Experiential purchases therefore, compared to material ones, better represent one's true self (Carter and Gilovich, 2012). This may be the reason why experiences have greater impact on one's self (e.g., self-concept, selfimage, self-image) than materials (Thomas and Miller, 2013). Such impact, in turn, would generate greater happiness (Thomas and Miller 2013).
Because experiential purchases often include other people, and are more likely to be shared with others (Caprariello and Reis 2013;Raghunathan and Corfman 2006), the social connection and a sense of belonging with others facilitated by experiences can satisfy people's relatedness (Baumeister and Leary 1995). This may be the reason why experiences have greater impact on one's interpersonal relationship than materials, and such impact on interpersonal relationship would generate greater happiness for consumers themselves (Thomas and Miller 2013).
Overall, then, experiential purchases are more enjoyable because they foster successful social relationships and become a meaningful part of one's identity (Howell and Hill 2009;Van Boven 2005). Research also suggests that consumers engaging in experiential purchases are liked more than those engaging in material purchases (Van Boven, Campbell and Gilovich 2010); and people derive greater happiness from waiting for an experience than waiting to receive a material good (Kumar, Killingsworth and Gilovich, 2014).
From the review above, we can identify multiple gaps within this stream of research. First, the extent to which consumers tend to distribute WOM about experiential purchases versus material ones has not been explored. Second, purchase type has not been examined in the social media context. Third, prior research has not looked into how materialism may moderate the effects of purchase type.

Enjoyment with Purchases
Consumer enjoyment with purchases has been operationalized by three main constructs that are independent of each other. These constructs are: consumption emotions (e.g., Richins, 1997), consumer satisfaction (e.g., Westbrook and Reilly, 1983) and happiness derived from purchases (e.g. Van Boven and Gilovich, 2003). Next is a review of these three constructs.

Consumption Emotions
Westbrook and Oliver (1991) define consumption emotions as the set of emotional responses that are evoked specifically during product usage or consumption experiences, as described either by the distinctive categories of emotional experience and expression (e.g., joy, anger, and fear) or by the structural dimensions underlying emotional categories, such as pleasantness/unpleasantness, relaxation/action, or calmness/excitement. Similarly, Richins (1997) defines consumption emotions as directly experienced emotions that result from the consumption of products. They are the range of emotions consumers most frequently experience in consumption situations including anticipatory product acquisition, as well as post-purchase possession and use of the product. Consumption emotions provide a useful means of understanding the complex nature of product benefits and customer value (Havlena and Holbrook, 1986).
Consumption emotions so far have been examined mostly in the post-purchase context. For example, Ladhari (2007) suggests that positive post-purchase consumption emotions have significantly positive effects on WOM. Consumption emotions, however, can also be evoked before consumers make a purchase. Richins (2013) finds that at the pre-purchase stage, higher-materialism consumers experience stronger positive product-evoked emotions than lower-materialism consumers. Indeed, when anticipating a desired consumption item, such as an upcoming vacation, it is quite common to feel positive emotions like excitement, because desire is passionate imagining of good life (Belk, Ger and Askegaard, 2003).

Consumer Satisfaction
As a second measure of enjoyment with purchase, consumer satisfaction has been typically conceptualized as either an emotional or cognitive response, with more researchers classifying satisfaction as an emotional response (Giese and Cote, 2000).
According to Westbrook and Reilly (1983), satisfaction is an emotional response to the experiences provided by purchases. Oliver, one of the major researchers on consumer satisfaction, defines the construct as pleasurable fulfillment (Oliver, 1997). That is, the consumer senses that consumption fulfills some need, desire, goal; and that such fulfillment is pleasurable. Thus, satisfaction can be seen as confirmation or a disconfirmation of consumption outcomes against a standard of pleasure versus displeasure.
Research suggests that consumption emotions impact consumer satisfaction.
Emotions may not only come into play during actual consumption but also prior to consumption, when consumers form expectations (Klaaren, Hodges, and Wilson, 1994;Wilson, et al., 1989), and after consumption, when they compare experienced emotions with anticipated emotions and form their response regarding satisfaction (Westbrook, 1980;Westbrook and Oliver, 1991). Consumption emotions are evoked not only as a consequence of the superior or inferior performance of the product on functional attributes but also in terms of whether emotional pleasure can be attained through consumption or not (Hirschman and Holbrook, 1982). Thus, consumers may form affective expectations about how consumption of the product will make them feel, based on either past emotional experiences with products (Sujan, Bettman, and Baumgartner, 1993) or visions of future emotionally based consumption experiences (Phillips, Olson, and Baumgartner, 1995). Consumers' overall satisfaction will depend on pre-purchase affective expectations, the emotions actually experienced during consumption, and the discrepancy between experienced and anticipated emotions (Philips and Baumgartner, 2002).

Happiness with Purchases
Another kind of enjoyment that consumers may attain from their purchases is overall happiness, which is a psychological state but not a specific consumption emotion.
As reviewed above, a recent stream of research has examined how different purchase types (experiential vs. material) influence consumers' happiness (e.g., Van Boven and Gilovich, 2003;Nicolao, Irwin and Goodman, 2009 The review on consumer enjoyment suggests two main research gaps. First, enjoyment with consumption items has not been investigated in the social media context.
For example, consumption emotions happening at the pre-purchase stage of the consumption process may be more manifest, as social media enables consumers to easily reveal their desire towards consumption items. Second, as mentioned above, how WOM influences the storyteller's enjoyment with consumption items is underexplored.

Summary of Research Gaps
This section summarizes the main research gaps identified at the end of each

CHAPTER 3: RESEARCH FRAMEWORK AND HYPOTHESES
In Chapter 2, I point out that there are multiple gaps existing in the research on social media, WOM, purchase type, materialism, and enjoyment with consumption. To address those gaps, I develop a research framework (Figure 3.1) which covers both the antecedents and consequences of CPB on social media.
The antecedents are intrinsic enjoyment of using social media, the motivation to express oneself and attract attention via WOM (CSWOM), and purchase type.
Materialism is expected to moderate the effect of purchase type. The consequences of CPB on consumers' enjoyment with purchases are expected to be moderated by materialism. It is proposed that posting influences enjoyment with purchase through purchase's impacts on self and interpersonal relationships.
This chapter will explain the framework in detail and introduce specific hypotheses.

Hypothesis 1 -Intrinsic Enjoyment of Using Social Media
Social Media are generally understood as Internet-based applications in which the contents are generated and publicly shared by its users (Kaplan and Haenlein, 2010).
As reviewed in Chapter 2, research has identified the intrinsic enjoyment of using social media and online communities. Similarly, intrinsic enjoyment may also contribute to CPB on social media. This is due to unique characteristics of social media. Social media platforms are designed to encourage self-presentation (boyd and Ellison, 2008). Social norms that dictate modesty in offline interactions are absent or suppressed in social media interactions (Wilcox and Stephen, 2013). People feel that they are able to express their "true self" better on social media than in offline face-to-face contexts because of perceived anonymity and invisibility online (Belk, 2013). Online rejection or criticism towards self-presentation attempts is less likely to be noticed (Miller and Arnold, 2001).
As a result, self-presentation on social media can be more flexible and enjoyable than offline. There is more self-disclosure on social media (Belk, 2013) and it becomes much easier to present ourselves in ways that may be less appropriate in offline situations. For example, displaying and talking about our possessions on social media is acceptable whereas showing off our possessions in offline social gatherings is considered to be rude (Belk, 2013).
Because social media are intrinsically enjoyable, posting consumption items on social media offers an interesting a way to present and express oneself. It is hypothesized that: H1: Intrinsic enjoyment of using social media drives CPB on social media.

Hypothesis 2 -Consumption-Focused Self-Expression Word of Mouth (CSWOM)
Chapter 2 introduced the idea that CSWOM is a motivation to engage in WOM to express oneself and attract attention to oneself (Saenger, Thomas and Johnson, 2013).
As social media encourage self-presentation, it seems that posting one's consumption items on social media is about self-expression and attracting attention. Therefore, it is hypothesized that:

H2:
The motivation to express oneself through consumption-focused WOM (CSWOM) drives CPB on social media.

Hypothesis 3 -Purchase Type
As reviewed in Chapter 2, people enjoy experiential purchases more than material purchases (e.g., Carter and Gilovich, 2011;Van Boven and Gilovich, 2003).
Moreover, consumers engaging in experiential purchases are liked more than those engaging in material purchases (Van Boven, et. al, 2010). Due to these reasons, purchase type should predict CPB on social media.

H3:
Purchase type predicts CPB on social media. Specifically, experiential purchases are more likely to be posted on social media than material purchases.

Hypothesis 4 -The Moderating Role of Materialism
Research suggests that higher-materialism consumers would enjoy experiential purchases as much as material ones. Nicolao et al. (2009) demonstrate that highermaterialism consumers are as happy with positive experiential purchases as positive material purchases. Millar and Thomas (2009) indicate that higher-materialism consumers associate material purchases with more happiness and rate them as more selfrelevant than experiences. Compared to lower-materialism consumers, highermaterialism consumers are more likely to purchase material products which are easy to display publicly (Fitzmaurice, 2008). In contrast, lower-materialism consumers tend to engage in more experiential purchases (Tatzel, 2003). Because of these reasons, I hypothesize that materialism may moderate the influence of purchase type on CPB on social media.
H4a: Lower-materialism consumers are more likely to post experiential purchases on social media than material purchases.
H4b: Purchase type has no effect on higher-materialism consumers' CPB on social media.
The proposed antecedents of CPB on social media are shown in Figure 3.2.

Hypothesis 5 -The Moderating Role of Materialism
Posting consumption items on social media provides consumers an alternative opportunity to interact with their friends and family. For example, when a consumer is boating on a beautiful lake and posts the moment on her social media, the experience becomes a shared oneher audience is able to witness the experience with her, and interact with her about the boating experience (e.g., by "liking" or commenting). The consumption experience thus allows the consumer to bond with her audience. Recall that in Chapter 2 the literature suggests that lower-materialism consumers value relatedness with others more than external recognition (Kasser, 2002). Thus, posting purchases on social media may lead lower-materialism consumers to enjoy their purchases more since the purchases help them attain what they valueinterpersonal interaction.
In contrast, for high-materialism consumers who value external praise, financial success, and self-image more than connection with others (Kasser, 2002), the purpose of CPB on social media is likely to be more for conspicuous reasons (e.g., showing off wealth and promoting self-image) than bonding with their social networks. Nevertheless, because it is difficult to tailor self-presentation content on social media (Wilcox and Stephen, 2013), the effect of showing-off on social media may not be better than doing it offline. Consequently, higher-materialism consumers are not likely to enjoy their purchases more because of social media posting.
The moderating role of materialism in the effect of CPB on enjoyment with purchase is hypothesized below and shown in Figure 3.3.
H5a: CPB on social media leads lower-materialism consumers to enjoy their purchases more.
H5b: CPB on social media has no effect on how higher-materialism consumers enjoy their purchases.

Hypothesis 6 -The Mediating Role of Purchase's Impact
As social media allow users to record personal history, CPB on social media can be seen as recording the purchases into one's personal history. The posted purchase, regardless of its type, becomes more like a life experience. For example, when a college student posts about a new car that is paid for by a part-time job, the student is actually updating his/her life experience. Because experiences have more impact on one's self (e.g., self-concept, self-image, self-image) than materials (Thomas and Miller, 2013), the college student may perceive that the car has greater impact on his/her self. Such impact, in turn, would generate more enjoyment for the consumer (Thomas and Miller, 2013).
Moreover, as mentioned above, CPB on social media creates another opportunity to interact with a person's social network. Continuing with the above example, the college student would discuss the new car with his/her friends on social media through the comments on the posting. Consequently, consumers may perceive that the purchases posted have greater impact on their interpersonal relationships.
Research has demonstrated that increases in social interactions are associated with increases in happiness (Argyle and Crossland, 1987;Diener and Seligman, 2002;Kasser, 2002;Oishi and Koo, 2008). The increased impact on relationship from the purchase, in turn, would contribute to more enjoyment for the consumer (Thomas and Miller, 2013

Overview of Studies
Six studies were designed to systematically investigate the proposed framework of the antecedents and consequences of CPB on social media.
Studies 1-5 used undergraduate students while Study 6 gathered survey responses from an Amazon MTurk sample, in order to test whether results from student samples could be replicated by a different, more externally valid sample.
The research designs included surveys as well as experiments. Studies 1, 5 and 6 utilized surveys to obtain participants reports on their actual posting behavior. Studies 2, 3 and 4 were experiments in which the posting behavior was manipulated.
The studies included purchases actually made by the participants, purchases the participants desired to make, as well as a common purchase that all the participants were asked imagine that they made. Studies 1, 2, 5 and 6 asked participants to report a recent purchase they had actually made and the type (material or experiential) of the purchase.
The prices of the purchases were also collected in order to test if price acted as a confound. Study 3 asked participants to report a purchase they desired to make, in order to examine CPB on social media in a pre-consumption context. Study 4 asked participants to imagine they had purchased a specific consumption item (cruise), which allowed control of the self-selection bias.
Antecedents of CPB on social media were tested by multiple studies. Intrinsic enjoyment of using social media (H1) were tested in Studies 1, 2, 5 and 6. CSWOM (H2) were tested in Studies 1, 5, 6. Purchase type (H3) were tested in Studies 1, 2, 5, 6, and moderation of materialism in the effect of purchase type on posting (H4) were tested in Study 1 and Study 6.
Consequences of CPB on social media (H5 and H6) were also investigated in several studies. The mediation of purchase's impact between CPB and enjoyment with purchase (H5) was tested in Study 5 and Study 6. The moderation of materialism in the effect of CPB on enjoyment with purchase (H6) was tested in Studies 1-4 and Study 6.
The overall framework with hypotheses and studies is shown below in Figure   4.1. As shown in the figure, each hypothesis was tested in at least 2 studies. The data collected from each study were analyzed with appropriate statistical techniques. The antecedents were tested by regression models. The moderating roles of materialism in both purchase type on CPB and CPB on enjoyment with purchase were tested by floodlight analyses. The mediating roles of purchase's impact on self and interpersonal relationship between CPB on social media and enjoyment with purchase were tested by bootstrapping analyses.
Since each hypothesis was tested in multiple studies, details of specific scale used to operationalize the construct is summarized in Table 4.1. Scales for CSWOM, materialism, impact of purchase on self and interpersonal relationship, post-purchase satisfaction, consumption emotions (joy and excitement) and happiness evoked by purchase were all adopted from previous research. Since no scale measuring intrinsic enjoyment of using social media exists, a single-item scale was created to measure it.
Single-item measures have been demonstrated to have equally high predictive validity as multi-item scales Rossiter, 2007, 2009

Purpose and Participants
Study 1 tested H1 -H5 through a web-based survey. 108 undergraduate students (51 female; average age 18.12) who were social media users participated in the survey in exchange for course credits.

Procedure
The participants were first asked to identify an important purchase that they had made during the past 6 months and if they had shared the purchase on social media.
They were given the definition of material and experiential purchase and asked to selfcode the type of their own purchase. Then they were asked the price paid for the purchase. Next post-purchase satisfaction, materialism, CSWOM and intrinsic enjoyment of using social media was measured. Finally they answered a few demographic questions including gender and age.

Results
Among the 108 participants, 30 reported that they had posted their purchases on social media (27.8%). The price of the purchase did not correlate with satisfaction with the purchase (B = 0.31, NS), eliminating the possibility of price being a confounding variable.
To test H1 -H3, three logistic regression models were conducted with CPB on social media as dependent variable (DV) (coded 1 = shared, 0 = did not share). Intrinsic enjoyment of using social media, CSWOM, and purchase type (coded 1 = experiential, 0 = material) was the independent variable (IV) respectively in each of the three models.
The results reveal that enjoyment of using social media ( To better understand the interaction, I used a floodlight analysis (Johnson-Neyman technique) (Spiller et al. 2013;e.g. Kristofferson, White and Peloza, 2014) to identify the range of materialism for which the simple effect of purchase type was significant. This analysis revealed that purchase type had a significant positive influence on posting for the participants whose materialism value was lower than 4.02 (BJN = 1.38, SE = .70, Wald = 3.88, df =1, p = .05), but not for those whose materialism value was higher than 4.02. This indicates that lower-materialism consumers are more likely to post experiential purchases than material purchases, but higher-materialism consumers are equally likely to post the two types of purchases. H4a and H4b are thus supported.
To test H5a

Discussion
Study 1 provides initial support for the antecedents of CPB (H1 -H4). Intrinsic enjoyment of using social media positively predicted CPB on social media. Participants who had stronger motivation to express themselves and attract attention through wordof-mouth (CSWOM) were more likely to post their purchases on social media. The results also show that experiential purchases were more likely to be posted on social media than material purchases, but materialism moderated the effect. While lowermaterialism participants were more likely to post experiential purchases, highermaterialism participants were equally likely to post material and experiential purchases.
The results of Study 1 also provide initial support for the moderating role of materialism on the consequences of CPB on social media. As predicted in H5, the results reveal that lower-materialism participants were more satisfied with their purchases if the purchases were posted on social media, but higher-materialism participants did not demonstrate such a pattern. However, one can argue that this finding is not the result of CPB on social media, but of something else happened during the time gap between the purchase and the survey participation, or from personal selection biaspeople may post the purchases that they enjoy, but not the purchases that they do not enjoy that much.
To eliminate such possibilities, Studies 2, 3 and 4 were designed to test the H5 in alternative ways.

Purpose and Participants
The purpose of Study 2 was to replicate the results of Study 1 that supported H1 and H3 which propose that intrinsic enjoyment of using social media and purchase type motivate CPB on social media, as well as H5a and H5b which propose the moderating role of materialism on the consequences of CPB on social media. In Study 2, actual purchases were retained as in Study 1. However, actual posting behavior was manipulated in order to provide a closer investigation of the effects of CPB on social media and to test H5a and H5b. 100 undergraduate (52 female; average age 18.74) students who were social media users participated in the study in exchange for extra credits.

Procedure
Participants were first asked to describe an important purchase that they had made during the past 6 months. Then they were asked if they had posted the purchase on social media. Participants who answered "yes" were then measured on their enjoyment of using social media and answered demographic questions. Participants who answered "no" were then requested to post their purchases on their social media. They were allowed to click away to a social media site of their choice and return to the survey.
Next they responded to questions on post-purchase satisfaction as well as materialism value. Following that, they were asked to indicate honestly if they had actually posted the purchase on social media as requested, being notified that their answers would not influence receiving the extra credits. Finally they responded to the questions about their enjoyment of using social media and demographics.

Results
Among  consumers. H5a and H5b were thus supported again. The results of Study 2 also further support H1 and H3 that intrinsic motivation of using social media and purchase type predict CPB on social media.

Purpose and Participants
As discussed in Chapter 2, social media not only allows consumers to post purchases which are already made, but also allows consumers to post desired consumption items before they make the purchases. The purpose of Study 3 was to test H5a and H5b in a pre-consumption scenario to see if the effects of posting also manifest at the pre-consumption stage.
86 undergraduate students (48 female; average age 20.03) who were social media users participated in the study in exchange for extra credits.

Procedure
Participants were first asked to describe a consumption item that they desire to acquire. Then they were asked to post the desired consumption item on social media.
Next they reported their excitement with the desired consumption item instead of postpurchase satisfaction. Following that, they responded to the materialism scale. Finally they were asked to honestly identify if they had actually posted the consumption item on social media as the experiment asked them to do, being notified that their answers would not influence them getting the extra credits.

Results
Among the 86 participants, 45 (52%) indicated that they did post the desired consumption item on social media and 43 indicated that they did not. To test H5a and

Discussion
The results of Study 3 provide additional support for the H5a and H5b that CPB on social media leads lower-materialism consumers to be more excited with a desired consumption item, but does not have such an effect on higher-materialism consumers.
The results demonstrate that the influences of CPB on social media are not only salient post purchases, but also before the purchases are madewhen consumers desire to acquire consumption items.

Study 4
Purposes and Participants 176 undergraduate students (78 female; average age 19.42) who were social media users participated in the study in exchange for extra credits.

Procedure
Participants were randomly assigned to the social media or offline condition. Cruise was selected as the consumption item after a pretest confirming college students were generally interested in this category. All the participants first watched a 30-second advertisement video of a Carnival cruise, and then were asked to imagine that they had just come back from the cruise. Next, participants who were randomly assigned to the social media condition were shown two examples of Instagram postings of cruise trips and asked to imagine that they had posted the experience on social media. Participants who were randomly assigned to the offline condition were shown a picture of a group of young people having a conversation and asked to imagine that they shared the experience with their friends in a face-to-face conversation. Then the participants were asked how joyful they would be with the purchase. Joy was measured instead of satisfaction or excitement because this study used an imagined postpurchase scenario. Next the participants were measured on their materialism value.
Finally the participants finished with the manipulation check question "What did this task ask you to do?" and selected an option from "Imagine that I go on a cruise vacation and post it on social media", "Imagine that I go on a cruise vacation and share the news with my friends in face-to-face conversations", "Imagine that I go on a cruise vacation and write this into my diary".

Results
97% of the participants selected the correct answer for the manipulation check.
The manipulation was thus successful. To test H5a and H5b, first, a regression was  The results of Study 4 further support H5a and H5b by eliminating personal selection bias as the possible explanation of CPB effects. Participants were all given the same consumption item (a cruise) and were randomly assigned to a social media CPB group or an offline WOM group. The results are consistent with Studies 1, 2 and 3: CPB on social media leads lower-materialism consumers to enjoy their purchases more, but has no such effect on higher-materialism consumers.
Study 4 also reveals the differences between social media CPB and offline WOM. The results suggest that CPB on social media is a new type of WOM; it has different influences on lower-materialism consumers than traditional offline WOM.
Specifically, CPB on social media leads lower-materialism consumers to enjoy their purchases more compared to traditional offline WOM.

Purposes and Participants
The main purpose of Study 5 was to test H6a and H6b that purchase's impact on self and interpersonal relationship mediate the effect of CPB on enjoyment with purchase. Another purpose of Study 5 was to replicate the findings from previous studies that supported H1 -H3 (antecedents of CPB on social media: intrinsic enjoyment of using social media, CSWOM and purchase type).
196 undergraduate students (103 female, average age 20.69) who were social media users participated in exchange for extra credits and a chance to win a $10 coffee gift card.

Procedure
In order to eliminate the personal selection of purchase type as a bias, participants were randomly assigned to a material purchase or an experiential purchase condition. Participants who were in the material (vs. experiential) purchase condition were asked to describe an important material (vs. experiential) purchase that they had made during the past 6 months. Then they were asked if they had posted the purchase on social media. Next, they reported their happiness with the purchase.
Then they answered questions about the impact of the purchase on self and interpersonal relationships. Next they completed the scales of intrinsic enjoyment of using social media and CSWOM. Finally they indicated the price of the purchase and answered demographic questions. To test H1 -H3, three logistic regressions were conducted with CPB on social media as DV (coded 1 = shared, 0 = did not share) and CSWOM, intrinsic enjoyment of using social media and consumption type (coded 1 = experiential, 0 = material) as IV respectively in each of the three models. The results reveal that intrinsic enjoyment of using social media significantly predicted CPB on social media (B = .81, S.E. = .24, Wald = 11.03, df = 1, p < .01). Also, CSWOM significantly predicted CPB on social media (B = .74, S.E. = .14, Wald = 4.94, df = 1, p < .05). Consumption type as well significantly predicted CPB on social media (B = 1.02, S.E. = .40, Wald = 6.56, df = 1, p < .05). Experiential purchases were more likely to be posted on social media than material purchases. H1 -H3 are once again supported.

33
To test H6a and H6b, the mediating roles of purchase's impact on self and interpersonal relationship between CPB on social media and enjoyment of the purchase, a bootstrapping analysis was used to verify the mediation (Zhao, Lynch and Chen, 2010).
The method uses 5000 bootstrapped samples to estimate the accelerated confidence intervals. I first examined the indirect effects of CPB on happiness with the purchase, through the mediator of purchase's impact on self. The indirect effect (β = .34, SE = .12) from the bootstrap analysis was significant, with a 95% confidence interval excluding zero [.12 to .58]. I then examined the indirect effects of CPB on happiness with the purchase, through the mediator of purchase's impact on interpersonal relationships. The indirect effect (β = .29, SE = .10) from the bootstrapping analysis was also significant, with a 95% confidence interval excluding zero [.14 to .54]. These results reveal that CPB on social media is responsible for the increased impact of the purchases on consumers' self and interpersonal relationships, which then lead to greater happiness with the purchases. H6a and H6b are thus supported.

Discussion
Study 5 tested H6a and H6b and demonstrated that CPB on social media affects enjoyment with purchases through the purchases' impact on self and interpersonal relationship. It also replicated the findings of Study 1 and 2 in terms of the antecedents of CPB on social media. The results confirm that intrinsic enjoyment of using social media, CSWOM and purchase type respectively predicts CPB on social media.

Study 6
Purpose and Participants

Procedure
The participants were first asked to identify an important purchase that they had made during the past 6 months and if they had shared the purchase on social media.
They were given the definition of material and experiential purchase and asked to selfcode the type of that purchase. Then they were asked to indicate the price of the purchase.
Next they responded to the scales of materialism, CSWOM and happiness with the purchase. Finally they answered demographic questions.

Results
Among

Discussion
The results of Study 6 replicated the findings of the previous studies with a different population, thus successfully generalizing the findings. The results confirm that intrinsic enjoyment of using social media, CSWOM and purchase type are the antecedents of CPB on social media. Materialism works as a moderator on the effect of purchase type on posting. Lower-materialism consumers are more likely to post experiential purchases than material purchases, but higher-materialism consumers are equally likely to post the two types of purchases.
Even through a different measure of enjoyment with purchase was used in Study 6 compared to Studies 1 -4, we found the same effect on consequences of CPB on social media. Specifically, CPB on social media led lower-materialism consumers to enjoy their purchases morethe purchases brought them more happiness, while posting had no such effects on higher-materialism consumers. Study 6 also confirms the results from Study 5 that CPB on social media influences enjoyment with purchases through the impact of the purchase on self and interpersonal relationship.

Summary of Study Designs and Results
To summarize the overall study designs and results, Table 4.2 shows each hypothesis and the studies that tested it, as well as the scenarios of the studies and if the hypothesis was supported by the results. For example, the convenience of transmitting WOM messages on social media encourages storytellers to share their consumption experiences; the broadcasting, asynchronous and archived characteristics of social media may make storytellers perceive that the posted purchases have more meaningful impacts on themselves.
Fourth, this dissertation research suggests that in the contemporary social media context, conspicuous purposes can be achieved not only with publicly consumed products, but also privately used products and experiential purchases. All these products or experiences are amenable to being "shown off" on social media. This suggests how conspicuous consumption is being transformed by social media.
Fifth, existing research on social media mostly focuses on the influences of social media (e.g., Wilcox and Stephen, 2013), but what drives certain behaviors on social media has been underexplored. This dissertation fills this gap by identifying the antecedents that lead to CPB on social media.
Sixth, while there have been research studies on user-generated content (UGC) on social media, most of them focus on the motivations for creating UGC (e.g., Daugherty, Eastin and Bright, 2008;Heinonen, 2011) or the effects of UGC on companies' performance (e.g., Tirunillai and Tellis, 2012;Dhar and Chang, 2009). How creating UGC influences creators themselves has not been paid research attention. This dissertation sheds light on this research topic of UGC.
This dissertation also has important research implications for WOM. The results not only resonate with existing research (e.g.,  that WOM on social media is different from traditional WOM, but also demonstrate that the specific type of WOM on social mediaposting consumption items to express oneself and attract attention, or to interact with others, or to show offhas remarkable effects on how consumers enjoy their own consumption items. This dissertation thus contributes to the research on how WOM influences the storytellers, which has not received much attention in WOM research (Moore, 2012), as most of the existing WOM research has focused only on the motivations that drive WOM and how it impacts the receivers. This dissertation is also the first to examine how materialism moderates the influences of WOM. The findings suggests that the effects of WOM may vary due to personal values such as materialism.
Additionally, this dissertation advances our understanding of materialism. It shows that under certain circumstances (posting purchases on social media), lowermaterialism consumers will enjoy their purchases more, and they are as willing as higher-materialism consumers to talk about their purchases. This is interesting because it is different from lower-materialism consumers' behavior offline, in which highermaterialism consumers are more likely to display acquisitions (Goldsmith and Clark, 2012;Podoshen and Andrzejewski, 2012;Richins, 1994;Wong and Ahuvia, 1998). This suggests that CPB on social media may change the relationship between lowermaterialism consumers and their possessions. Perhaps the reason is that CPB on social media provides additional opportunity for lower-materialism consumers to interact with others. This suggests that interpersonal interaction may change how lower-materialism consumers view their own purchases. In addition, there is very limited research that looks into how materialism influences consumption emotions (Richins, 2013). The dissertation is one of the few research studies that investigate how materialism influences enjoyment with purchases.
Furthermore, this dissertation has significant implications for the differences between experiential and material purchases. Although numerous studies have shown that experiential purchases make people happier than material purchases (e.g., Van Boven and Gilovich, 2003;Carter and Gilovich, 2012), past research has not investigated how the purchase type influences WOM or the moderating role of materialism in the effects of purchase type. My results demonstrate that while experiential purchases are more likely to be posted on social media, higher-materialism consumers tend to post both material and experiential purchases. This brings much needed research attention to the potential moderators in the influences of purchase type.
Finally, the present research is a response to Pham (2013) who points out that consumer behavior researchers should not only focus on one particular stage (the Acquisition stage) of the overall consumption process. The findings shed light on the substantial influences of posting purchases on both the Desire and the Use/Consumption stage of consumer behavior. More importantly, while no prior research has investigated WOM or conspicuous consumption on the Desire stage, this dissertation fills this gap.
As shown in Study 3, posting purchases on social media has positive effects on lowermaterialism consumers but not on higher-materialism consumers even in the prepurchase scenario.
Managerially, this dissertation suggests the ways to encourage user-generated content on social media. As experiential purchases are more likely to be posted than material purchases, marketers may consider reframing the buying/using context so as to make consumers perceive their products to be more experiential. For example, marketers for 3D TV can word their advertisements with "a TV that transforms your TV-watching experience" rather than "a TV that you deserve to acquire as a new possession". Since intrinsic enjoyment of using social media and self-expression motivation through word-of-mouth (CSWOM) motivate CPB on social media, marketers can consider making their social media pages more enjoyable, as well as encouraging their audiences to express themselves more via CPB on social media. This dissertation also suggests the way to improve how consumers perceive their purchases.
Because the results point out that lower-materialism consumers are the group of people who enjoy their purchases more after posting the purchases on social media, marketers may consider not emphasizing materialism values on social media.

Limitations and Future Research
As with many research studies, this dissertation is not without limitations.
Although different designs were used to test the hypotheses, none of them dealt with a real purchase that was universal to each participant. Such a common-purchase based design may, to a great extent, eliminate the influences of varying products. Also, a design that randomly assigns participants to post the real purchase to their own social media pages right after the purchase happens could also eliminate some cofounding variables. Future research can look into how to work with such research designs to test these and related hypotheses.
The second limitation of this research is that it only explores positive emotions that resulted from CPB on social media. Future research should examine the kinds of circumstances under which CPB on social media leads to negative emotions or perceptions towards the purchases, such as receiving negative comments on postings.
In addition, this dissertation reveals that CPB on social media increases consumers' perceived impact of purchase on themselves and interpersonal relationships, but it did not test if the effect was a result of the CPB itself or of the audience's reactions to the postings (e.g., likes, comments). This could be tested in future research studies.
This research did not directly test the mechanism underlying the moderation of materialism in the consequences of posting. A possible reason is that the posting behavior enables lower-materialism consumers to connect with their social networks, which fulfills their intrinsic life goal of relatedness. On the other hand, "showing-off" on social media may not be more effective because the audience is large and diverse, therefore CPB on social media may not fulfill higher-materialism consumers' extrinsic life goal of 'looking good' in ways better than offline methods. Future research can test the underlying mechanism, using offline and online settings, to empirically explore this phenomenon further.
Another limitation of this dissertation is that the measures were captured at the same time in each study. This leads to a common method variance. Future research could consider different study designs to overcome this limitation.
Also, although this research has identified three antecedents that motivate the posting behaviors, there may be additional antecedents. Future research could explore these. Another opportunity for future research entails extending the topics to long-term effects of posting. Longitudinal research that explores the ways in which posting purchases on social media influences how consumers memorize the consumption experiences is needed.