Motivations of guests contributing sWOM on social media: a case in Vietnam

Abstract

Purpose

This paper examines whether guests contribute sWOM (social word of mouth) on different SNSs (social networking sites) regarding various personal motivations. SNSs have changed the way guests eat and experience their food and dishes. Marketing managers have effectively targeted SNSs as a marketing tool, yet have little research about drivers of guests' sWOM contribution on SNSs has been done. A model including the significant motives: (1) experiences, (2) opinion leadership, (3) reflection of self and (4) need for unique is tested to investigate their positive effects on contribution behavior of social media guests.

Design/methodology/approach

The data collected from 411 guests by using the snowball method was used for analysis. The structural equation modeling was applied to examine the relationships among the constructs and test the eight proposed hypotheses.

Findings

Results reveal that experiences, opinion leadership, reflection of self and need for unique were positively associated with contributing sWOM of restaurants. Furthermore, those who have positive experiences tend to be opinion leadership and reflection of self. And guests who show reflection of self, they are more likely to have opinion leaders and show need for uniqueness. Our study expands the existing frameworks of sWOM contribution by identifying various motivations and labeling sWOM. Findings provide restaurant managers with managerial implications for online marketing strategies on SNSs to attract sWOM contribution among guests.

Research limitations/implications

It has some limitations while discovering the motivations of positive sWOM contribution. First, we only focused on the motivation of contributing positive sWOM, while negative sWOM received many arguments in changing attitudes toward buying products or services. Second, we collected data in Vietnam only without comparing with different countries. Future research could explore further cross-cultural perspectives to fill the gap. Third, this study explored sWOM contribution in service environment, sWOM contribution from service context may be slightly different from those of product brands.

Practical implications

These findings highlight the motivations of sWOM contribution that restaurant managers must recognize and make use of it. SNSs have given power to consumers to post everything at anytime and anywhere they like, therefore restaurant managers need to deeply understand why their consumers contribute sWOM. In digital era, customers and guests have become the ultimate tools for promoting product or service brands. The marketing managers should create an online platform in order to facilitate their consumers to discuss their brand frequently (Charu et al., 2018). Restaurants should have policies to push positive eWOM maximally and also reduce advertising costs.

Originality/value

This is one of the first studies on sWOM contribution of what motivate guests to contribute their sWOM on SNSs. Theoretically, this study offers deep insights into the links between various motivations and sWOM in foodservice context. Managerially, understanding these motivations allow marketing managers create effective policies that motivate guests to contribute positive word of mouth.

Citation

Thanh Ha, L.T. and Thu, V.T. (2022), "Motivations of guests contributing sWOM on social media: a case in Vietnam", Journal of Asian Business and Economic Studies, Vol. 29 No. 2, pp. 146-162. https://doi.org/10.1108/JABES-05-2020-0055

1. Introduction

According to Hootsuite's report in Jan 2020, there are more than 4.54 billion of Internet users and 3.8 billion active social online users worldwide. The report also says that Eastern Asia is one of the regions having the highest rate of using social networks in the world. The social network most used in many countries is Facebook, accounting for nearly 2.5 billion of users; followed by YouTube with about 2 billion. In Vietnam, Hootsuite reveals that the number of consumers using social platforms greatly increased in 2020 with more than 65 million people that was higher than the past year with 58 million. The average Vietnamese users are aged 18 to 45 (accounting for over 60% of total population), they usually visit different social networking sites (SNSs) within 150 minutes daily. The behavior of Vietnamese social network users is reported mainly to engage news or contribute their daily activities on social networks. The rapid growth of social online platforms has facilitated the increasing study of social media topics all over the world (Chu and Kim, 2011). In Vietnam, this topic seems to be new and fragmented, has not received much attention from researchers, educators or practitioners as well.

SNSs facilitate consumers' process such as seeking information before making buying decision and sharing their consumption experiences with others within a few seconds (Sijoria et al., 2018). Organizations are putting significant resources in encouraging consumers to contribute eWOM with hoping to stimulate purchase intentions (Alhidari et al., 2015). The widespread connection of social media platforms leads to the generation of the new term, sWOM that is referred by Eisingerich et al. (2015). sWOM takes more advantages than eWOM because contributors are defined and clarified (Balaji et al., 2016). In spite of the potential influence on marketing campaign, why and how sWOM contributing on the online social environment has not fully been examined.

Practitioners and academicians are aware of the power of eWOM in SNSs or sWOM and have had numerous studies in recent years (Gvili and Levy, 2018). There are two general approaches in researching eWOM/sWOM: (1) eWOM/sWOM consumption includes reading or consuming such as impacting consumer attitudes, buying intentions/decisions (Vermeulen and Seegers, 2009; Chong et al., 2018; Khammash and Griffiths, 2011; Rauniar et al., 2014) or factors affecting eWOM/ sWOM's using acceptance (Cheung et al., 2008; Mumuni et al., 2019); (2) eWOM/sWOM contribution is engagement behaviors such as writing, sharing or forwarding topics on social networks (Kimet al., 2015a, b; Gvili and Levy, 2018). However, studies which have explored drivers affecting consumers' sWOM contribution on SNSs are slightly rare (Styvén and Foster, 2018).

Such studies interested in sWOM contribution stream indicate that sWOM contribution behaviors are influenced by two main groups of factors: (1) various attributes of sWOM such as Perceived credibility, Trustworthiness or Perceived ease of use (Ma et al., 2014; Doma et al., 2015; Casaló et al., 2008); and/or (2) motivations such as Opinion leadership (Ma et al., 2014; Kim et al., 2015a, b; Styvén and Foster, 2018), Social relationships (Chu and Kim, 2011; Choi et al., 2017; Belarmino and Koh, 2018), Reflected Appraisal of Self (Styvén and Foster, 2018). In spite of increasing number of research papers about sWOM contribution, the understanding of eWOM mechanisms to spread sWOM is still limited (Chu and Kim, 2011; Mahapatra and Mishra, 2017). This study expands various sWOM motivations that enhance customers to spread sWOM messages on SNS.

Online spreading daily activities via online platforms is an important symbol of a modern life (Kim et al., 2015a, b). Today, Vietnamese young adults often take photos of the dishes and restaurants they go to, and then upload on SNSs such as Facebook, Twitter or Instagram. Social media users are encouraged, and sometimes reminded that they need to share everything such as unforgettable moments, bonding experiences, thoughts, remarkable photos and meaningful videos daily or even for hours. A large number of different topics are discussed publicly on various online platforms. One of hot trends on Vietnamese online social environment is now sharing of food and dishes. Vietnamese famous food blogger said that food deepens people's communication because everyone eats every day. While the posts about restaurants on SNSs were often in the text before, now these contents are demonstrated with graphic photos and video that receive much interaction on social networks. In recent years, online restaurant review platforms such as Diadiemanuong, Foody, Lozi or Food Bloggers have been being rapidly growing. Food and beverage industry ranks third in online sales, with a growth rate of 24% (Hootsuite, 2020). Social media content about reputable restaurants also appeals to young people who actively join. Food and dishes could be a way to express oneself style or expertise. For restaurant businesses, the impact of online word of mouth is particularly deep-rooted. Because guests cannot evaluate food services before eating, online opinion reviews from experienced guests can provide them confidence to make buying decisions (Zhang et al., 2010). Restaurant experts have been recently aware of the importance of eWOM and have to explore how to stimulate positive online reviews from their consumers. Although researchers have confirmed the great significance of eWOM in the foodservice area (Litvin et al., 2008), but studies investigating why guests tend to spread sWOM on SNSs are limited. Rising in number of food reviewers across platforms is a good opportunity for restaurants to set an effective marketing campaign. Therefore, understanding or predicting who will share content with others is so important for restaurant managers.

The above-mentioned remainings will be uncovered in this study by expanding the understanding of motivations of contributing restaurant sWOM on SNSs. Our purpose is to develop a conceptual model that assists our full understanding of what drives guests to contribute their sWOM on SNSs. Our study also tests a model proposing personal motives of sWOM contribution via SNSs. Theoretically, this study offers deep insights into the links between various motivations and sWOM in foodservice context. Managerially, understanding these motivations allow marketing managers to create effective policies that motivate guests to contribute positive word of mouth.

2. Literature review

2.1 Social word of mouth (sWOM)

Traditional WOM has being replaced by the electronic word of mouth (eWOM) which is known as a new form of communication. The shift from traditional WOM to eWOM is likely to update the marketing frameworks and theories (Whiting et al., 2019). The revolution of communication technology allows consumers to share and forward consumption experiences with not only their relatives and friends but also with a larger online community quickly and conveniently (Kim et al., 2015a, b). eWOM is defined as “any positive or negative statement made by potential, actual or former customers about a product or company, which is made available to a multitude of people and institutions via the internet” (Hennig-Thurau et al., 2004). eWOM plays a typical function in sharing the postpurchase experience, posting online reviews, photos and videos on SNSs (Alhidari et al., 2015). Previous studies focused in the pre-purchase stage, eWOM attracts many researchers because of their substantial characteristic of source credibility (Lo and Lin, 2017).

The advent of Internet can be considered as the originator of Social networking sites (SNSs), leading to the creation of widely used SNSs such as Facebook (in 2004), Twitter (in 2006) and Instagram (in 2010) (Kaplan and Haenlein, 2010). Kaplan and Haenlein (2010) defined “Social networking sites are applications that enable users to connect by creating personal information profiles, inviting friends and colleagues to have access to those profiles, and sending e-mails and instant messages between each other”. SNSs topics are increasingly attracting more academics and researchers because of their degree of reaching and connections (Boyd and Ellison, 2007). SNSs supply interactive services that allow consumers to regularly contribute product-related information, share buying/consumption experiences and eventually give goods advice with their social network members (Patterson, 2012). Although these online social platforms have rapidly grown and changed traditional business models, but marketing research analysts have only begun to explore (Hennig-Thurau et al., 2013).

When SNSs such as Facebook, Twitter or Youtube were publicly launched, the widespread use of social media platforms leads to the generation of a new term, sWOM that was developed by Eisingerich et al. (2015). Consumers not only share or contribute product experiences but also reach global consumers with similar interests without geographical or time limits (Doma et al., 2015). Furthermore, SNS now is a mainly popular platform for contributing consumers' experiences and product or service news in a short time and likely cost-free (Whiting et al., 2019). The explosive rise of these SNSs enable customers to play an extremely active role as market guiders and reach (and be reached by) almost everyone at anywhere and anytime (Hennig-Thurau et al., 2010). sWOM is a new form of eWOM so sWOM shares certain characteristics with eWOM, including that consumers comfortably share their buying experiences, thoughts at the most convenient of time and place (Eisingerich et al., 2015). Unlike eWOM, sWOM has the comparative advantage of credibility because the contributors are identified and self-liable (Balaji et al., 2016). It is not surprising that sWOM may play a role as a low-cost advertising tool. Thus, an investigation of sWOM as an online marketing tool is timely and needed.

Prior studies explored that positive WOM is likely to increase consumers' purchase intentions because it reduces exchange risks (Dichter 1966), subsequently minimize a firm's marketing cost, so it is undoubtedly a powerful promotion tool (Sundaram et al., 1998). Although there are some studies regarding sWOM, the specific drivers of positive sWOM messages have not been fully discovered in foodservice context.

2.2 sWOM contribution

The importance of a comprehensive study in customer purchase behavior and customer engagement behavior are same (Van Doorn et al., 2010). While the influence of WOM or eWOM on purchasing a product or service has been explored by many scholars, the concept of user engagement is relatively less noticed (Rossmann et al., 2016). Engagement is defined as a two-way interaction between the consumer and the specific object (e.g., a brand or a company) (Halaszovich and Nel, 2017). Van Doorn et al. (2010) defined “customer engagement behavior the customers' behavioral manifestation, can be both positive and negative, toward a brand or firm, beyond purchase, resulting from motivational drivers”. There are various behaviors relating to customer engagement including WOM and eWOM, recommendations, helping other customers, writing reviews, posting consumption experiences but not limited in sharing brand reviews, and referrals (Van Doorn et al., 2010; Rossmann et al., 2016; Gvili and Levy, 2018). Our conceptualization is similar, but it is narrower, we prefer the term “sWOM contribution” that captures positive interactions between consumers, and/or other members of an online social community. Based on uses and gratifications theory, online contribution activities on SNSs that users make are positive and active (Dolan et al., 2019). Based on previous studies in SNS topic, we list sWOM contribution activities in the context of SNSs including reacting (like and emotion), sharing, commenting, posting and forwarding product news to their social connections.

Over SNSs, consumers are willing to post contents frequently as their friends need to do (Chen et al., 2013). Especially, SNSs enable consumers' active connection in the online communication progress immediately and costlessly so SNS has become a trendy platform for sharing consumer experiences (Gvili and Levy, 2018). Previous papers mentioned that consumers may contribute their sWOM on social platforms because of two significant reasons: (1) various attributes of sWOM (e.g. Ma et al., 2014; Doma et al., 2015; Casaló et al., 2008) and/or (2) motivations (e.g. Kim et al., 2015a, b; Styvén and Foster, 2018; Whiting et al., 2019). Furthermore, the numbers of literature papers on motivations are less than attributes of sWOM (Whiting et al., 2019). Our primary objective of this study is to explore a comprehensive and integrated set of drivers of sWOM contribution to deeply understand customer engagement behavior.

2.3 Drivers of sWOM contribution and hypotheses

Previous papers researched in eWOM contribution have shown that consumers spread eWOM due to two significant reasons: (1) various attributes of eWOM: e.g. Perceived ease of use (Ruix-Mafe et al., 2014; Casaló et al., 2008); or Perceived credibility (Ma et al., 2014; Doma et al., 2015; Mahapatra and Mishra, 2017) and/or (2) different motivations: e.g. Opinion leadership (Sun et al., 2006; Bilgihan, 2014; Kim et al., 2015a, b; Styvén and Foster, 2018); Reflected Appraisal of Self or Self-Enhancement (Hennig-Thurau et al., 2004; Styvén and Foster, 2018; Belamino and Koh, 2018); enhancing Social relationships (Chu and Sung, 2015; Kim et al., 2015a, b; Choi et al., 2017). Overall, there are many researches in motivations but they are fragmented and only focus on eWOM, rarely mentioned in sWOM behavior. We expect to find some different drivers of sWOM contribution in term of Vietnamese restaurant context.

Based on a thorough literature review on drivers of sWOM contribution, we aim to find out and derive what motivate guests to contribute food sWOM on SNSs. Dichter (1966) defined four drivers of traditional positive WOM: product involvement, self-involvement, other-involvement and message involvement. Hennig-Thurau et al. (2004) developed positive eWOM drivers with four scales: social benefits, economic incentives, helping the company and extraversion/positive self-enhancement. Along with the rapid increase of social online consumers, researchers have paid their attention to the motives of eWOM in social media. Kim et al. (2015a, b) explored that personal motives such as positive social outcome expectations were significant factors of information sharing. Kim et al. (2015a, b) suggested a conceptual model of sharing food eWOM with such motivate factors Reflected appraisal of self and Self-Image Congruency. Travelers are willing to contribute their positive reviews on online opinion platforms or SNS because of reflected appraisal of self, opinion leadership, travel experience and need for uniqueness. Recently, Whiting et al. (2019) added four motives of positive eWOM such as Helping company, Product involvement, Self-enhancement and Altruism (see Table 1). Thus, studies on the motivation in contribution sWOM have been examined, but still not sufficient to explain why guests spread eWOM in social networking platforms. In foodservice, Vietnamese marketers recognize the valuable role of eWOM and are eager to explore them when young adults surf the social network a dozen times a day, worry about what to post and how to make others admire their lives. These online behaviors mean that young people, who have unique needs, want to express themselves or like to enhance themselves will tend to interact with social networks. Other studies in service context also suggest that consumers are willing to contribute eWOM because they want to share their experiences with friends or relatives (Rossmann et al., 2016). Based on our review of these studies, we propose four drivers of positive sWOM contribution within foodservices: (1) experiences, (2) opinion leadership, (3) reflection of self and (4) need for unique. We explain and clarify these four motivations to set a theoretical framework as below.

2.3.1 Experiences

Prior studies validate that experiences with products or services are a powerful marketing tool because they are one of the most significant drivers lead to one's buying decision and may affect the individual's consumption choices (Hyde et al., 2011). Experiences are explained as the degree of familiarity with a specified product or service at consumers' expertise. We define the restaurant experiences as their prior consumption experience of visited contributors.

Consumers attain a lot of experiences with the product or service in a long-term connection; they will share their useful information to other consumers. In online context, such consumers are more likely to contribute vital online sources and perceived knowledge (Rossmann et al., 2016). Sharing positive experiences after using the service will increase the positive effects and also reduce the negative assessment (Kim and Fesenmaier, 2017). Social media platforms like Facebook or Instagram now provide different tools for consumers to interact and share information with friends or followers. Social media users are encouraged, and sometimes reminded, that they need to share everything or experiences daily, even hourly.

Styvén and Foster (2018) suggested that travelling experiences were positively related to the intention of sharing travel experiences on social media during or after trips. Indeed, a common phenomenon nowadays in Vietnam is that young adults “check-in” food and share food stories, e.g. photos or clips as the way of the technology lifestyle. Therefore, we propose that the more food experiences guests have, the more they are likely to contribute sWOM. So, we suggest the following hypothesis is:

H1.

The restaurant experience guest owned, positively affects her/his sWOM contribution on SNSs.

2.3.2 Opinion leadership

Summers (1970) says that any individuals with opinion leadership, called opinion leaders, are the consumers those have more experience or expertise in products/services and they have ability to influence the decisions of other consumers. Because of these abilities, opinion leaders play an important role in the consumer decision-making process and therefore may enhance the results of the marketing strategies (Flynn et al., 1996). Collected from 410 published papers, Jungnickel (2018) confirmed three substantial characteristics of opinion leadership: (1) Having a special impact on others' opinions and behaviors, (2) Opinion leaders influence others through direct and indirect communications and (3) opinion leaders can be at every social level, all sexes, all occupations and age groups. Furthermore, Kim et al. (2015a, b) added one more element, opinion leaders are the information generators. Opinion leaders are willing to contribute their opinions rather than non-leaders in both online and offline contexts (Bilgihan et al., 2014). Opinion leaders can attract other consumers in numerous ways in different environments (Flynn et al., 1996). Thus, opinion leaders can be anyone as long as they tend to influence others by sharing news or information.

Along with the explosive growth of Internet, online opinion leaders are also keen to use the Internet for a longer period and more frequently than non-leaders so they have more opportunities to share their knowledge and information about products/services with consumers without a lot of efforts (Lyons and Henderson, 2005). Kim et al. (2015a, b) stressed that the intention to share eWOM may be depended on the degree of the opinion leadership consumers have. Especially, online opinion leaders usually possess a large number of followers or subscribers, so the reaching extents of shared news widely expand as they contribute online messages on SNSs (Ma et al., 2014). In the service sector such as tourism, recent studies have found that the more travelers are likely to become opinion leaders, the more they are willing to write online reviews about their trips (Styvén and Foster, 2018). Hence we expect that there is a positive relationship between opinion leadership and sWOM contribution which means that consumers who tend to be opinion leaders, are more willing to contribute sWOM on SNSs. So we suggest the following hypothesis:

H2.

Guest with a higher opinion leadership tendency is with higher intention to contribute restaurant sWOM on SNSs.

2.3.3 Reflection of self

This term was first named self-enhancement by Sundaram et al. (1998). He defined that if any consumer tended to set up a special self-image in others' views, he was self-enhancement. When an individual has self-enhancement motive, he tries to get others' attention and prove superiority (Whiting et al., 2019). Self-enhancement is sorted in approval utility group concerning satisfied or excited feelings of consumers that lead to positive eWOM (Hennig-Thurau et al., 2004). Because of getting a positive recognition, consumers are more likely to spread positive traditional WOM to protect their images as an intelligent consumer (Sundaram et al., 1998). Previous researches have shown that this motive is the primary reason for consumers to participate in the generation of eWOM on online platforms (Hennig-Thurau et al., 2004; Kim et al., 2015a, b; Styvén and Foster, 2018; Whiting et al., 2019). In particular, consumers tend to contribute their opinions on SNSs because they want to reflect on how they desire to be seen by friends (Eastman et al., 2014).

Self-enhancement term was used by Sundaram et al. (1998) and Hennig-Thurau et al. (2004). This motivation was renamed Reflected Appraisal of Self by Styven and Forster (2018) and Kim et al. (2015a, b). But we decide to label the term “reflection of self” because it was close and familiar to with Vietnamese culture. Contributing daily consumption on social online platforms is an important sharing of a modern lifestyle and a way to shape a self-image (Styvén and Foster, 2018). Individuals join online social networks not only to post related information but also interact with others in the purpose of expanding their self-identity online (Kim et al., 2015a, b). Furthermore, online social platforms now launch marketing policies to encourage users to actively contribute their thoughts and opinions by ranking top fan. These policies allow online consumers to become a connoisseur or an expert of information diffusion that can be an important part of self-enhancement motivation. Thus, when guests desire to receive positive recognition from others, they are highly motivated to contribute food sWOM on SNSs publicly. We expect that the more reflection of self guests have, the more food sWOM they will contribute. So, we suggest the following hypothesis:

H3.

Guest with a higher reflection of self tendency is more likely to contribute restaurant sWOM on SNSs.

2.3.4 Need for uniqueness

In addition to highly being aware of how others view themselves, consumers often wish to feel superior and different from others on online social platforms which is labeled need for uniqueness (Styvén and Foster, 2018). The theory of the need for uniqueness was first mentioned by Snyder and Fromkin in 1977. Need for uniqueness indicates a positive striving to set individuals apart from the crowd and being unique (Snyder and Fromkin, 1977). Consumers who have need for uniqueness enjoy being center of attention, feeling superior and independent in opinions (Snyder and Fromkin, 1977). Besides, consumers are continually seeking the uniqueness for the purpose of being recognized and appreciated by others (Hyun and Park, 2016). In order to achieve the main characteristics of need for uniqueness, consumers regularly commercialize and popularize products for the purpose of developing and boosting their self-image (Tian et al., 2001). In other words, when consumers are in pursuit of uniqueness or differentiation within a large group, they are likely to express their uniqueness by sharing their experiences to others.

Styvén and Foster (2018) confirmed that the choice of the travel destination is a strategy for consumers to prove their uniqueness, and then share their trip photos to others via social media. Previous studies show that the younger travelers adopt social media as a place to express their uniqueness or difference, the more they are likely to contribute eWOM on social media (Wallström et al., 2015). Today, Vietnamese young adults are acquainted with going to a restaurant or a coffee shop, checking in and posting photos on online social walls to get distinctive recognition from their online friends. Such interactions on SNSs are similar to the way to demonstrate their individuality and uniqueness (Song and Lee, 2013). So, we suggest the following hypothesis:

H4.

The more need for unique a guest has, the more he/she is likely to contribute restaurant sWOM on SNSs.

Closely related to improve self-images, consumers tend to share their experiences on online platforms. By using symbols and digital tools on personal web space, consumers have more opportunities to post the product-related information or photos for the purpose of representing and expressing their self-concepts (Jensen Schau and Gilly, 2003). Further, consumers are authoring and posting their consumption experiences on the Internet to receive professional self-images from others (Kim et al., 2015a, b). Clearly, need for receiving positive recognition from others is a motive for consumers to publicly communicate their consumption experience on SNSs. Kim et al. (2015a, b) also pointed out that consumers are more likely to post their experiences widely if these experiences are perceived to be important to themselves, which lead to be considered as an opinion leader in that field. Furthermore, because consumers benefit from the advanced technological skills, they are motivated to continuously improve their online content (Jensen Schau and Gilly, 2003).

In addition, consumers tending to be opinion leaders have the ability to influence others based on two requirements: (1) knowledge of a specific field or problem and (2) the ability to communicate with others (Kim et al., 2015a, b). Knowledge is related to the information that is kept in an individual's deep memory (Ratchford, 2001). Particularly, unforgettable experiences are all structured for attaching individuals' determined knowledge (Hyde et al., 2011). Recent studies have also shown that online opinion leaders usually have greater knowledge about products/services than non-leaders (Eastman et al., 2014). Jungnickel (2018) summarized that opinion leaders were main players of innovation diffusion because they got powerful abilities of spreading innovations and influencing others to accept them. Opinion leaders are very likely to communicate with others because of their knowledge and experiences in products or services (Flynn et al., 1996). Based on the relationship between opinion leadership and innovation, opinion leaders always welcome new products, then share product-related information and consumption experience to their groups (Lyons and Henderson, 2005). Therefore, the more experience or knowledge opinion leaders accumulate, the more online news they post to attract their followers. So, we suggest the following hypotheses are

H5.

The experience guests have with the restaurant is positively associated with opinion leadership on SNSs.

H6.

The experience guests have with the restaurant is positively associated with their reflection of self on SNSs.

Based on uniqueness theory, consumers with high needs for uniqueness are expected to more often buy products for the purposes of self-enhancement rather than using (Tian et al., 2001). When a customer seeks to be different from others, he purchases goods classified in a manner that matches and supports his self-image (Tian et al., 2001). Clearly, because of this motivation, guests go to unique restaurants to gain desired social image from others that enhances their self-image or reflect themselves.

Styvén and Foster (2018) explored that there was a strong relationship between reflection of self and need for uniqueness in the tourism service. In virtual social, consumers are more interested in what and how they be appraised. The eating destinations become a tool to express a positive impression with friends on social platforms, which is an attribute of opinion leaders (Lyons and Henderson, 2005). So we assume that guests seeking for reflection of self have led to an increased need for uniqueness. So, we suggest the following hypotheses:

H7.

Reflection of self will positively affect opinion leadership on SNSs.

H8.

Reflection of self will positively affect need for uniqueness on SNSs.

Accordingly, the following theoretical model is suggested: (see Figure 1)

3. Methodology

3.1 Measurement items and variables

sWOM contributions are online interactive activities such as “Liking” and/or “sharing” restaurant-related content to personal social media profile. They are positive and active contributions on social media foodservice pages. sWOM contributions are measured by adapting four items from Kim et al., 2015a, b and Rossmann et al. (2016). Based on previous papers of Kim and Fesenmaier (2017) and Styvén and Foster (2018), four items of experiences are developed and modified to fit foodservice. Participants are asked about their perceptions of foodservice experience. The measurement of opinion leadership is designed on perceptions of consumers' abilities to spread positive news on SNSs. Opinion Leadership scale is measured by four various items, originated from Ma et al. (2014). Reflection of self was identified as a construct of consumer motivations for the purpose of getting positive recognition from others. The measurement of reflection of self is phrased by three items based on Kim et al. (2015a, b). The measurement of Need for uniqueness is regarded as a feeling of setting individuals apart from their reference groups. Motivation of Need for uniqueness is measured with four items, based on Hyun and Park (2016). All 19 items and variables are measured using a five-point Likert-type scale, ranging from 1 (strongly disagree) to 5 (strongly agree).

All items and variables we take from the previous studies in various fields, so we need to verify before launching the official test. In order to verify, we combine qualitative and quantitative method for first phase. We invited seven professionals in the restaurant area for the purpose of evaluating all variables and items, including three professors specialized in marketing and four current restaurant marketing managers. The results are the basis for adjusting the research questionnaire to fit the Vietnamese people and restaurant scenario. Next, we conduct a pilot test with 113 samples in order to check the reliability of the measurement scales. All of the Cronbach's alpha values were greater than 0.6 which is the acceptable (Hair et al., 2010).

The official survey questionnaire is measured by 19 items of 5 measurements regarding Experiences, Opinion Leadership, Reflection of Self, Need for uniqueness and sWOM contribution. The survey questionnaire is also added extra questions such as demographics (e.g. gender, age, education, occupation); consumer online behavior (e.g. frequency to login SNS, length of using experience on SNSs, amount of time spent on SNSs and list of online regular activities).

3.2 Sample collection

We used virtual snow-ball sampling technique to identify the target responses. Virtual snow-ball sampling technique is a sampling method based on virtual networks to study “hard-to-reach” populations (Baltar and Brunet, 2012). In order to gather a reliable official sample, we set a sample criterion with the following characteristics: First, participants must be between 18 and 45 years old which the age group is actively participating in social networks (Hootsuite, 2020). Second, participants have logged into restaurant social networking sites to check in or/and leave comments. Third, the sample must be large enough for formal quantitative analysis. We sent invitations to the targeted participants via Facebook and in addition we requested them to further pass it in their friend circle to get more and more responses.

In total, 411 participants were collected. Participants were distributed across the four main social platforms in Viet Nam as follows: Facebook (99.3%), Youtube (83.7%), Instagram (55.0%), Twitter (15.3%) and others such as ZingMe, Linkedin (9.73%). The sample was evenly distributed in terms of gender with 44.3% male respondents and 55.7% female. A large percentage of guests were 18–34 years old (82.5%) with an average or above-average income (77.2%). 97.6% of guests have using experiences on SNSs are over 3 years. Their frequency is more than five times per day (66.2%). All daily activities on social media platforms include: React (82.0%), Comment (69.34%), Forward (43.55%), Share (68.1%) and View (91.24%). The collected data are controlled as samples descriptions are similar to the report of Vietnam Digital 2020 Data Analysis for Marketing issued by Hootsuite statistics. We may conclude this collected sample be a part of the crowd.

3.3 Data analysis

Two main statistical analyses were performed. First, confirmatory factor analysis (CFA) was conducted to test how well the measured variables represent the constructs (Hair et al., 2010). Second, structural equation modeling (SEM) was applied to examine the eight proposed hypotheses and structural model. The software AMOS (20.0) was used.

4. Results

4.1 Validity and reliability

Before testing the research model, all variables and items were first conducted to confirmatory factor analysis (CFA) to evaluate the validity of the measurement constructs. The results of the entire measurement model affirm the construct validity of the measurement model. As Chi-square/df = 1.913 was lower than the suggested 3.0 value; goodness-of-fit (GFI) = 0.935 and comparative fit index (CFI) = 0.970 which all exceeded the critical level of 0.90; and root mean square error of approximation (RMSEA) = 0.047 which is between 0.03 and 0.08 (Hair et al., 2010). The discriminant and convergent validity among constructs was assessed by examining the alpha values of all five constructs ranged from 0.824 to 0.908 that exceeding the minimum requirement for reliability of 0.70 (Hair et al., 2010); standardized factor loadings for all items ranged from 0.683 to 0.898; the average variance extracted (AVE) of all constructs ranged from 0.544 to 0.712, exceeding the recommended 0.5 that mean the variance was explained by these constructs (Hair et al., 2010). These above criteria were affirmed the construct validity of the measurement model (see Table 2).

4.2 Structural results and hypothesis tests

We next proceeded to conduct SEM to examine the relationships among the constructs and test the proposed hypotheses. The overall fit statistics exhibit an acceptable level of fit (chi-square/df = 2.264; GFI = 0.923; CFI = 0.958; and RMSEA = 0.056), indicating that the path model is valid (Hair et al., 2010). The structural results of the SEM suggest that our proposed model would offer a good fit for the data.

All eight of hypothesized relationships were supported. The hypothesized relationship between guests' experiences and sWOM contribution (H1) was significant (β = 0.387, p = 0.000). This result suggests that guests have more rich experiences, the more likely they are willing to contribute sWOM on SNSs. The hypothesized relationship between opinion leadership and sWOM contribution (H2) was supported by a significant estimate (β = 0. 144, p = 0.015). These findings indicated that guests have a perception of opinion leadership, are very likely to communicate with others in both offline and online environments. The hypothesized relationship between reflection of self and sWOM contribution (H3) was significantly supported (β = 0.177, p = 0.002). The result suggests that guests seek the positive recognition by their online posts, they are willing to contribute sWOM. The hypothesized relationship between need for uniqueness and sWOM contribution (H4) was significantly supported (β = 0.192, p = 0.003). The result suggests that consumers seek uniqueness, they are willing to contribute sWOM. Furthermore, guests' experience was significantly associated with both opinion leadership (β = 0. 367, p = 0.000) and reflection of self (β = 0.598, p = 0.000) that supporting H5 and H6. Reflection of self was significantly associated with both opinion leadership (β = 0.290, p = 0.000) and need for uniqueness (β = 0.328, p = 0.000) that supporting H7 and H8. The results are presented in Table 3.

5. Conclusions

5.1 Discussion

SNSs change how guests eat and experience toward restaurants. The primary goals of this study are aimed to explore various motivations having impacts on contributing positive sWOM about restaurants on SNSs. To our knowledge there are only few studies which focus on exploring the different motivations of positive sWOM contribution through SNSs, especially in term of personal motivation. Our study develops the further literature of why guests actively spread sWOM on online social platforms. A better understanding of consumers' motivation in contributing sWOM through SNSs can support companies to control and manage their brands and their digital marketing campaigns. The structural equation model of main motivations for contributing positive sWOM was developed and tested. We found that guests contribute sWOM on SNSs for several reasons relating to Experiences, Opinion Leadership, Reflection of Self and Need for Uniqueness. The strongest influence on sWOM contribution is guests' experiences. It means that great experiences are the prime motivations that make guests share restaurant information with their friends. The second largest motive is Need for uniqueness. sWOM is now a tool to facilitate consumers' individuality and uniqueness. We also found that Opinion Leadership and Reflection of Self are significantly related to sWOM contribution on SNSs. Our findings are supportive of the previous studies concerning the sharing of their travel information during the trip in order to be different and unique (Styvén and Foster, 2018). Opinion leaders are willing to use the Internet to share news more frequently (Bilgihan et al., 2014; Styvén and Foster, 2018). Guests, who tend to be opinion leaders, actively contribute sWOM about the restaurants they visited. Experiences and Reflection of Self are positively correlated with Opinion Leadership, it is consistent with previous studies (Styvén and Foster, 2018).

Interestingly, however, we also found some slightly different results from previous studies. For example, we found that Reflection of Self and Experiences are significantly related to sWOM contribution when they are not significantly related to the propensity to share travel experiences (Styvén and Foster, 2018). The more restaurant experience guests accumulate, the higher tendency in contributing sWOM they will have. Being happy to share restaurant experiences is one of the characteristics of Vietnamese youth lifestyle. Guests who are food-addicts looking for unique culinary experiences, always upload or share experience photos or video on various SNSs.

5.2 Theoretical implications

sWOM provides many opportunities and challenges for digital marketing management (Lee et al., 2019). The importance of sWOM contribution makes many scholars pay their attention to explore, but researches on guests' motivations to contribute sWOM on SNSs are scarce. Our study addresses some important gaps in the literature by offering a comprehensive set of motivations to contribute sWOM toward restaurants on SNSs.

Our study contributes some important theoretical implications. We develop the literature in self-motivations in sWOM contribution, specifically restaurant context. Our study has responded to calls for further research on examining experience and reflection of self that have not any significant correlation with the propensity to share travel information (Styvén and Foster, 2018). We have continued to stress the importance for understanding the motive of Need for uniqueness, especially in Vietnam that is collective culture (Hyun and Park, 2016). Finally, this study established and labeled sWOM which is lacking the attention from Vietnamese researchers.

5.3 Managerial implications

Our findings contribute not only important theoretical but also managerial implications. These findings highlight the motivations of sWOM contribution that restaurant managers must recognize and make use of it. SNSs have given power to consumers to post everything at anytime and anywhere they like, therefore restaurant managers need to deeply understand why their consumers contribute sWOM. In digital era, customers and guests have become the ultimate tools for promoting product or service brands. The marketing managers should create an online platform in order to facilitate their consumers to discuss their brand frequently (Sijoria et al., 2018). Restaurants should have policies to stimulate positive eWOM maximally and also reduce advertising costs. Thus, restaurant managers may consider the following suggestions:

Services have special characteristics such as intangible, perishable and inseparable, so creating memorable experiences is the best way for guests to maintain online social connections with others. Vietnamese restaurants should heavily invest in restaurant marketing campaigns to generate unforgettable experiences. Besides, the restaurant managers need to identify the top fans and facilitate them to contribute their memorable experiences on the SNS.

Along with collective culture, Vietnam consumers' behaviors in terms of reflecting individual identity to an online group are an opportunity to stimulate positive sWOM contribution. Therefore, restaurant managers may be likely to design their products attaching self-image values that appeal to target customers. Restaurant managers should use SNS as advertising tools by encouraging their guests to post unique photos of the dishes and artful foods.

Opinion leaders diffuse product- or service-related information to countless online platforms that can increase consumers' purchase confidence. The results of this study also stress that marketers should pay more attention to consumers with opinion leadership who influence others in various ways. The followers tend to be influenced by their opinion leaders' activities (Sijoria et al., 2018). So the restaurant managers give incentive policies for opinion leaders to frequently discuss their brands on online social network for the purpose of creating a better image of a brand. In other words, restaurant managers could take opinion leaders as a strategic tool in generating positive sWOM as launching online marketing activities.

5.4 Limitations and future studies

It has some limitations while discovering the motivations of positive sWOM contribution. First, we only focused on the motivation of contributing positive sWOM, while negative sWOM received many arguments in changing attitudes toward buying products or services. Second, we collected data in Vietnam only without comparing with different countries. Future research could explore further cross-cultural perspectives to fill the gap. Third, this study explored sWOM contribution in service environment; sWOM contribution from service context may be slightly different from those of product brands.

Figures

Figure 1

Proposed theoretical model

Table 1

Positive Motives for eWOM/sWOM

No	Positive motives	eWOM/sWOM contribution	Context	Source
1.	Product involvement	Traditional WOM	Offline	Dichter (1966)
	Self-involvement
	Other-involvement
	Message-involvement
2.	Social benefits	General eWOM	Internet	Hennig-Thurau et al. (2004)
	Economic incentives
	Helping the company
	extraversion/positive self-enhancement
3.	Reflected appraisal of self	Food eWOM	SNS	Kim et al. (2015a, b)
	Self-Image congruency
4.	Social outcome	General eWOM	SNS	Kim et al. (2015a, b)
	Expectations
	Sharing enjoyment
5.	Reflected appraisal of self	Travel eWOM	SNS	Styvén and Foster (2018)
	Opinion leadership
	Travel experience
	Need for uniqueness
6.	Helping company, Product involvement, Self-enhancement and Altruism	General eWOM	SNS	Whiting et al. (2019)

Table 2

Correlation matrix (CFA results)

Variables and items	Load	Cronbach's α	AVE
Experiences		0.907	0.709
My experiences of these restaurants were memorable	0.828
My experiences of these restaurants were very interesting	0.855
My experiences of these restaurants enhance my dining experience	0.873
My experiences of these restaurants were different	0.810
Opinion leadership		0.829	0.549
Restaurant news I posted on SNS influence people's opinions	0.742
People access my SNS profile to update what the latest restaurant news I have contributed	0.726
My friends and followers on SNSs usually share restaurant news I posted	0.804
I usually share restaurant news, therefore my online friends consider me as an opinion leader in this area	0.687
Reflection of self		0.824	0.610
I usually post restaurant news I visited, just to let others know what kind of person I am	0.799
I often share restaurant news on SNS to get positive recognition from my friends	0.814
Sharing restaurant news on SNSs will make many people admire me	0.728
Need for unique		0.827	0.544
I usually post restaurant news as a way of proving to my online friends that I'm totally different	0.683
I usually write unique restaurant news to build up a style that is all my own	0.747
I usually write unique restaurant news to express my individuality	0.769
I usually write unique restaurant news to create a special image on SNSs	0.749
sWOM contribution		0.908	0.712
I often contribute restaurant news on SNSs	0.787
I usually share restaurant news on SNSs	0.796
I often forward restaurant news to my friends list on SNSs	0.898
I positively engage to comment on restaurant topics on SNSs	0.887

Table 3

Summary of structural results

Hypotheses		Path coefficient	S.E	t	Supported?
H1	Experiences → sWOM	0.387	0.063	6.107	Yes
H2	Opinion leadership → sWOM	0.144	0.059	2.439	Yes
H3	Reflection of self → sWOM	0.177	0.058	3.055	Yes
H4	Need for uniqueness → sWOM	0.192	0.065	2.961	Yes
H5	Experiences → Opinion leadership	0.598	0.071	8.398	Yes
H6	Experiences → Reflection of self	0.367	0.067	5.472	Yes
H7	Reflection of self → Opinion leadership	0.290	0.056	5.180	Yes
H8	Reflection of self → Need for uniqueness	0.328	0.046	7.145	Yes

Note(s): p < 0.05