Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 The Impact of EWOM Referral, Celebrity Endorsement, and Information Quality on Purchase Decision: A Case of Instagram Randy Danniswara, University of Indonesia, Depok, Indonesia Puspa Sandhyaduhita, University of Indonesia, Depok, Indonesia Qorib Munajat, University of Indonesia, Depok, Indonesia ABSTRACT This study aims to explore factors that have impact on purchase decision on a social commerce, viz., social media Instagram. Thus, several dimensions namely eWOM referral, celebrity endorsement, information quality, brand satisfaction, brand trust and brand attachment are identified and examined. This research uses SEM method and LISREL 8.80 application. Data was collected using questionnaires with Likert scale. The result from 350 respondents shows that a significant positive correlation exists between eWOM referral and purchase intention, information quality and brand satisfaction, information quality and brand trust, brand satisfaction and brand attachment, brand satisfaction and purchase intention, brand trust and purchase intention, brand attachment and purchase decision, and also between purchase intention and purchase decision. Keywords Brand Attachment, Brand Satisfaction, Brand Trust, eWOM Referral, Information Quality, Instagram, LISREL 8.80, Marketing, Purchase Decision, Purchase Intention, SEM, Social Commerce, Social Media 1. INTRODUCTION Social media is a group of Internet-based applications that are built on Web 2.0 ideology and technology that allow information creation and exchange of the Internet users (Kaplan and Haenlein, 2009). The rapid growth of gadget development has been subsequently followed by the fast development of software applications which leads to social media as a new communication trend. Social media allows users to socialize with each other and interact without space and time limitation. The Internet and social media opens wide opportunities for consumers to engage in social interaction on the Internet as well as for trading companies to conduct a new way of marketing. According to Muniz and O’Guinn (2001) in Kaplan and Haenlein (2009), some companies are already using social networking to support brand community’s creativity. In addition, the social media platform has become an integral element for companies who want to develop a deep online customer relationship (Chen, Fay, and Wang, 2011). The marketing trend is known as the social media marketing which concerns the relationship which companies ought to change from “trying to sell” to “making connections” (Gordhamer, 2009). Businesses that engage consumers with social media is known as social commerce which is shaped into a dynamic and profitable e-commerce (Hajli and DOI: 10.4018/IRMJ.2017040102 Copyright © 2017, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. 23 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 Featherman, 2014). They further stated that social commerce could create an environment in which consumers turn into brand ambassadors. Another definition of social commerce comes from Paul (2009) in Adiputra (2013) who stated that social commerce is part of e-commerce that uses social media as an online media that supports social interaction and user contributions to help online purchase and sale of products and services. One of the social media that supports social media marketing is Instagram. According to Lisa Pomerantz, senior vice president of global communications and marketing Michael Kors, Instagram can connect companies with fans and inspire fans with nice pictures with a message in it. Furthermore, according to the Pew Research Center, Instagram is social media with the most rapid growth. According to Kotler (2000), purchase decision is a problem-solving process that consists of analyzing the needs and desires, information search, selection sources appraisal towards purchase alternative, purchase decisions, and behavior after purchase. Previous researches were not yet able to demonstrate the influence of social media, viz., Instagram from more than one aspect, on purchase decision. An example is the work of Dyah (2014) and Sari (2015) that discussed only the impact of celebrity endorserment of Instagram towards purchase intention. In addition, Goor (2012) and some articles on http://blog.business.instagram.com/ examined only the content and marketing strategy using Instragram, without explaining how the content and marketing strategy affect purchase decision. On the other side, companies have had beliefs towards Instragram as media to apply marketing strategies as supported by Simply Measured (2015) which found that in Q4 2014 86% of leading brands in the world are already using Instagram. Therefore, given the current belief and practice of these many companies, it is intriguing to observe and discover whether the belief and practice of using Instagram actually meets its underlying goal viz., have significant impact towards customers’ purchase decision. Hence, this study aims to explore aspects of Instragram, one of the existing and relatively popular social media these days, that could have significant correlation towards purchase decision. 2. SOCIAL MEDIA (INSTRAGRAM) AND COMMERCE Social media is divided into various forms such as social networking, Internet forums, weblogs, social blogs, micro blogging, wikis, podcasts, pictures, video, rating and social bookmarking (Kaplan & Haenlein, 2009). The increasing development of gadget technology makes the development of social media increase rapidly. One quite noticeable example is that the role of the conventional mass media to inform news already began to be replaced by social media given that social media has also evolved from a media to get in touch with family and friends to a media for consumers to obtain information about the company and the products sold. (Shankar et al., 2011 in Paquette, 2013). Through social media, companies can promote their products and form communities or online groups for consumers who like their brands (Kaplan & Haenlein, 2009). In addition, social media platform has become an integral element for companies who want to develop a deeper online customer relationship (Chen, Fay, & Wang, 2011). According to Gabisch and Gwebu (2011), social media is a valuable forum in the construction of a brand relationship with consumers. Social media marketers use all those types of online social media in persuading and influencing consumers to buy or use their company’s products and services. By using online communities, marketing through social media, or so-called social media marketing, have different strategy with traditional marketing in building brand image. Social media marketing makes the communication between companies and consumers became closer by presenting their brands rather than controlling their brand image (Gordhamer, 2009). According to him, social commerce can create an environment where consumers are turned into brand ambassadors. Next, according to Fisher (2010), the adoption of social networking introduces new components in e-commerce. Fisher (2010) divided those components into six categories namely social shopping, rating and reviews, recommendation and referrals, forums and communities, social media, and social advertising. Each component has its own challenges and advantages for the online shopping experience. 24 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 Instagram is one of social media-based social networking. Instagram has many features such as feature to take, edit, and share post in the form of picture or video, feature to tag people, and feature to explore picture and video that can be assisted using hashtag information. This photo-sharing application was launched in October 2010 and took about 19 months to reach 50 million users. In 2012, Instagram was bought by Facebook and in September 2014, the user reached 150 million. 3. BRAND RELATIONSHIP AND CONSUMER BEHAVIOUR Brand is a diffrentiator between products. According to the Law of the Republic of Indonesia Number 15 of 2001 on Brand, Chapter 1, Article 1, Paragraph 1, brand is a sign in the form of images, names, words, letters, numbers, color composition, or a combintation of those forms that is able to distinguish one product from others ad used in trading activities. Brand is also used by the company to provide evidence in the form of fixed standards, especially for companies that do not have the opportunity to develop relationships with customers continuously (Palmer, 2001 in Rizki, 2011). According to Kotler (2003) on Rizki (2011), brand plays important roles for producer as: identification means to facilitate the handling or tracking products; protection means towards features or unique aspects of products; identification means for satisfied customers for re-purchasing; means for creating associations and unique meaning to differentiate the product from competitors; competitive advantage through legal protection, customer loyalty and unique image; source of financial return especially future revenue. One that supports the formation of consumer emotional bond to products or brands is social media. According to Gabisch and Gwebu (2011), social media is a valuable forum in forming brand relationship with consumers. Marketers can interact with consumers frequently, and can form friendship or personal relationship through social media (Turri, Smith, and Kemp, 2013). Brand relationship serves a number of functions by providing a resource for consumers to make decisions, to meet their needs, and to motivate them to purchase the product. (Turri, Smith, & Kemp, 2013). Consumer behavious is an element in marketing activities that need to be well-understood by companies. Therefore, observing consumers behavious is important to understand consumer’s mind concerning company’s product or brand. According to Schiffman and Kanuk (1997) in Ghoniyah and An (2013), consumer behavior is a process through which user do searching for, buying, using, evaluating product, service or idea, and act after its consumption. Brand relationship elements such as brand satisfaction, brand trust and brand attachment (Esch et. al., 2006 in Lesmana, 2012) have an important role in affecting consumer behavior, especially in purchasing (Rekarti, 2012). A good relationship between consumers and a brand can give a positive impact as the consumer feels close and familiar to the brand. Therefore, the relationship between brand and consumers must be maintained so that consumers continue to use the brand despite in a form of different product. Customer satisfaction is the objective need to be achieved in business so that it requires marketers to accurately identify customer needs and develop products that meet the expectation of customer (Lancaster et al., 2005 dalam Palagan, 2012). According to Perner (2009) in Palagan (2012), knowledge of consumer behavior in purchasing a product can help marketers in developing marketing strategy. Therefore, marketers will gain better understanding about consumer behavior that helps them to meet customer needs effectively and increase consumer’s loyalty to their product and services. 4. RESEARCH CONCEPTUAL MODEL In developing the conceptual model, we adopt several theories as underlying rationale for the relationships among dimensions. 25 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 4.1. EWOM Referral and Its Relationship to Consumer Behaviour Electronic word of mouth (eWOM) is positive or negative statements made by potential customers, current customers or former customers, about the product or the company via the Internet (HennigThurau, Gwinner, Walsh et al., 2004). EWOM message is an important means for consumers to obtain information about product quality and service quality. (Chevalier & Mayzlin, 2003). Additionally, the eWOM message can also effectively reduce the risks and uncertainty perceived by the consumers when purchasing a product or service, which means eWom may affect in consumer purchasing decisions (Chattereje, 2001). The product review that consumers write on the Internet is the most important form of eWOM communication. Consumers tend to search for product reviews on internet in order to get information about a particular product. The online review searching will eventually build an interest in purchasing (Jalilvand & Samiei, 2012). The engagement of consumers in eWOM through social media is reflected in three behaviors, namely seeking opinion, giving opinion, and the opinion passing (Flynn et al, 1996; Themba & Mulala, 2012). Based on previous research, eWOM referral has a correlation with the behavior of consumer in seeking opinion. Opinion seeking behavior is performed by consumers who seek information and advice from other consumers when making purchasing decisions (Chu & Kim, 2011). Thus, the following hypotheses can be proposed as follows: Hypothesis 1: EWOM referral influences on purchase intention. Hypothesis 2: EWOM referral influences on purchase decision. 4.2. Celebrity Endorsement and Its Relationship to Brand Relationship and Consumer Behaviour Celebrity endorsement is recognized as a potential means in brand communication, where the celebrities are considered to have greater power than the anonymous models Carroll, 2008). According to Debiprased Mukherjee (2009), celebrity endorsement is considered as a winning formula in brand marketing and development. Marketers believe that the use of celebrity affect the effectiveness of marketing, brand recall and recognition, as well as purchase intent and action of consumers (Spry, Pappu, and Cornwell, 2009). For marketers, celebrity can be a valuable asset. A study by Chan, Ng, and Luk (2013) discussed the aspects related to celebrities based on previous research. A celebrity can give testimonial about the benefit of using certain product or services, support products or services, or act as spokesman of the endorsed product for a long period of time (Blackwell et al., 2006). Frequently, marketers chose celebrity who is interesting, trustworthy, or has expertise in area related to the brand image (Hakimi et al, 2011). Celebrities who are well-known and have good skill will make the consumers have more desires to purchase the advertised brand (Ohanian, 1991). According to Shimp (2003), endorser celebrity can be an artist, entertainer, athelete, or wellknown public figure recognised by people for its skill or expertise in an area that can support the brand he/she promoted. In this context, the endorser celebrity is a celebrity who supports the brand through social media marketing. The use of celebrity endorser can influence the consumer’s response towards a product that can make them consider purchasing a product without enforcement. With that influence, consumers will have positive perception towards the product (brand satisfaction). Furthermore, if they are able to buy the product, they will purchase it in the future (Shimp, 2003). Thus, the following hypotheses can be proposed as follows: Hypothesis 3: Celebrity endorsement influences on brand satisfaction. Hypothesis 4: Celebrity endorsement influences purchase intention. Hypothesis 5: Celebrity endorsement influences purchase decision. 26 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 4.3. Information Quality and Its Relationship to Brand Relationship and Consumer Behaviour Information quality is consumer’s perception towards information quality from a product that is provided by e-commerce website (Park & Kim, 2003). Perception is a process of accepting, selecting, organising, and giving meaning towards received stimuli (Pareek, 1983; Milton, 1981; Maskuri, 2010). According to Robbins (1991) on Maskuri (2010), three factors that influence perception are perceptors, target and situation. The characteristic of the observed target can be influenced by what target perceive towards movement, sound, size, or other attributes possessed by the target that will form its perspective. Therefore, the authors propose the following hypotheses: Hypothesis 6: Information quality influences on brand satisfaction. Hypothesis 7: Information quality influence on brand trust. Hypothesis 8: Information quality influence on purchase decision. 4.4. Brand Relationship and Its Relationship to Consumer Behaviour Satisfaction is a psychological response of customers as a result of a comparison between expectation and perceived reality after consuming a product (Kotler, 2000). According to Engel (1990) in Sreejesh (2014), brand satisfaction is the result of a subjective evaluation of the consumers where consumers are satisfied with the selected brand and that the brand is in line with their expectations. Brand attachment is defined as a psychological variable that expresses affective relationship to the brand that is durable; it states the relationship of psychological closeness to the brand (Lacoeuilhe, 2000 in Louis and Lombart, 2010). When customers are satisfied, they might gain certain attachment towards products’ brand. Additionally, they might also have intention to buy the product in the future. Thus, the authors propose the following hypotheses: Hypothesis 9: Brand satisfaction influences brand attachment. Hypothesis 10: Brand satisfaction influences purchase intention. In business, trust is usually called brand trust. Brand trust is consumers’ tendency to believe that the brand can keep the promise with respect to its performance (Fuller et al, 2008 at Yana and Siti, 2011). According to Chaudhuri and Holbrook (2001), brand trust is the desire of consumers in general who believe in a brand because it can meet the requirements and have the necessary skills to function. Meanwhile, according to Lau and Lee (1999) in Lesmana (2012), brand trust is the desire of consumers who rely on the brand, in a situation of risk, as they have expectations that the brand brings positive things. This could add customers’ attachment on the brand. In addition, this could also lead towards consumers’ intention to buy the product. Therefore, the following hypotheses can be proposed as follows: Hypothesis 11: Brand trust influences brand attachment. Hypothesis 12: Brand trust influences purchase intention. According to McAlexander (2003) and Thomson (2005) in Rekarti (2012), brand attachment creates connections and it could predict how often a particular brand is purchased in the past and will be purchased in the future. Thus, the authors conjecture the following hypothesis: Hypothesis 13: Brand attachment influences purchase decision 27 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 4.5. Relationship between Consumer Attitude and Behaviour One of the fundamental aspects of consumer behavior is consumers’ intention to buy. According to Keller (2013), consumers’ intention to buy could be expressed as the probability whether consumers would buy product of a brand or switch from one brand to another brand. Another study suggested that the interest to buy is a function of the monetary deliberation, not only of behavior (Rizwan, Qayyum, Qadeer and Javed, 2014). Thus, affordability is an economic aspect that could affect the intention regardless the product price. The Theory of Reasoned Action (TRA) developed by Martin Fishbein and Ajzen Icek is a model of social psychology theory that fundamentally explains the factors that drive human behavior. They suggested that a person’s actual behavior could be determined by considering his/her prior intention along with the belief that the person would have for the given behavior. Thus, the authors propose the following hypothesis: Hypothesis 14: Purchase intention influences purchase decision. Therefore, all hypotheses can be formulated as Figure 1. 5. METHODOLOGY 5.1. Data Collecting Procedure This research was quantitative and used a survey technique that was developed based on the research conceptual model (Figure 1). Before the questionnaire was distributed, readability test was performed towards 10 people with different educational background. The indicators were also reviewed by academician with marketing background. In order to get as many samples as possible, the questionnaires were distributed online using Google form. Figure 1. Conceptual Model 28 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 5.2. Instruments In the questionnaire, there are 8 dimensions with the total 35 statements (see Appendix) that contain all of the indicators in this research, each of which should be scored by the respondents for their agreements. For each statement, a Likert scale of 1 to 5 is provided to rate each indicator. Scale 1 is used to express “strongly disagree”, scale 2 is used to express “disagree”, scale 3 is used to express “neutral”, scale 4 is used to express “agree”, and scale 5 is used to express “strongly agree”. EWoM referral dimension is represented by 4 indicators. Celebrity endorsement dimension consists of 4 indicators. Information quality dimension has 6 dimensions. Brand satisfaction dimension is represented by 4 indicators. Brand trust dimension consists of 4 indicators. Brand attachment dimension has 5 indicators. Purchase intention dimension is represented by 4 indicators. Lastly, purchase decision consists of 4 indicators. 6. RESULTS 6.1. Respondent Demographics From the data collection, the authors obtained 350 respondents. Table 1 shows the demographics of the respondents who completed the questionnaires in this study. 6.2. Data Analysis First step to perform data analysis with LISREL is making a path diagram. This requires the following steps: changing raw data into data PRELIS, opening the path diagram, calling PRELIS data, and determining the exogenous-endogenous variables. Next, to identify the model the degree of freedom (df) should greater than the number of parameters to be estimated. The df in this research is 510. There are several criteria that must be met in using SEM method viz., sample size, data normality (Hair, Black, Babin et al., 2009), and offending estimates. The minimum sample size for 35 indicators Table 1. Respondent demographics Sex Respondents Profession Respondents Male 75 High School Student 10 Female 275 Student 293 Age Respondents Employee 41 16-20 180 Unemployee 6 21-25 163 Last Education Respondents >25 7 Junior High School 10 Following Online Shop Respondents High school 240 1-5 185 Bachelor 98 6-10 74 Master 2 > 10 91 Salary Respondents Instagram Experience Respondents < 1 millions 123 <1 year 50 > 1 millions 227 1-3 years 225 Location Respondents > 3 years 75 Java 289 Non Java 61 29 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 is 350 (Kline, 2005). Data normality can be tested by looking at the value of the P-Value Skewness and Kurtosis that must be greater than 0.05 after previously changing the data type into a continuous multivariate. Normality test results of this study can be seen in Table 2 and Table 3. It can be seen that the research model is not normal in univariate where the P-Value of ER3, ER4, BA2, and BA3 ≤ 0.05. In addition, the P-Value for multivariate test is 0.00 which is less than 0.05. Therefore, the authors decided to replace Maximum Likelihood (ML) estimation with Diagonally Weighted leasts Squares (DWLS) estimation (Soreh and Gorji, 2014; Kline, 2005) to perform parameter estimation and the subsequent steps. Next is testing the offending estimates. Offending estimates are negative error variances for existing constructs (Hair et al., 2009). The test results offending estimates from this study can be seen in Table 4 that exhits there is no negative errorvariance and no correlation coefficient is greater than 0.9. Next is to test the measurement model. First is to conduct validity test that asseses whether a variable measure what it should measure. According to Hair, Black, Babin, and Anderson (2009) variables have good validity to construct if the T-Values ​​greater than or equal to the critical value (≥1.96) and according to Sharma (1996) the standardized loading factor is greater than or equal to 0.60 (≥0.60). Based on the validity test results, ER3, ER4, CE1, CE4, IQ3, and IQ6 has loading factor below 0.6. Thus, those indicators are declared invalid and removed from the study, both for the overall reliability test and subsequent data processing. Second is to perform realibility test that evaluate the consistency of a measurement where high reliability shows that the indicators (variables observed) have a high consistency in measuring the construct / latent variables. According to Hair, Black, Babin, and Anderson (2009), for SEM measurement, reliability can be assessed using Construct Reliability Measure (CR) and Measure Variance Extracted (VE). Reliability of the construct is good if CR value ≥ 0.70 and VE value ≥ 0.50. Based on the results of the reliability test in this study, ER has a CR value under 0.7 while IQ and BS have a VE value below 0.5. However, the value is still acceptable when CR is greater than 0.6 and VE is greater than 0.4 (Fornell, 1981 in Huang et al., 2013). Last is to test the structural model. It is performed by evaluating the GoF between data and model (Hooper, Coughlan, and Mullen, 2008). The results are shown in Table 5. It can be seen that the Chi-Square and Chi-Square divided by degree of freedom (df) has values beyond threshold, however this could be disregarded as Chi-Square statistic nearly always rejcts the model when large samples are used and data could be considered normal (Hooper, Coughlan & Mullen, 2008). 6.3. Hypotheses Testing Results Table 6 shows the the hypotheses tests (T-values) based on the results of the structural model testing by using LISREL. Of the 14 hypotheses tested, only 8 hypotheses were accepted, while 6 others were rejected. 7. DISCUSSIONS AND IMPLICATIONS 7.1. Theoretical Implications H1: ER-PI (accepted) and H2: ER-PD (accepted). From the testing result of hypothesis H1, we find that EWOM referral from ‘comment’ and ‘tag people’ feature in Instagram influences customer purchase intention towards the corresponding brand. The ‘comment’ and ‘tag people’ feature enables Instagram users to see how many people are interested in the product. This finding shows that—for Indonesian people represented by the sample—attention, appraisal, and other positive responses about a brand influences Instagram user’s purchase intention. There is a tendency of people who intend to buy product online to check beforehand how many people are interested in that product and to search the product review from other customers. 30 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 Table 2. Test of Univariate Normality for Continuous Variables Test of Univariate Normality for Continuous Variables Code ER1 Skewness Kurtosis Skewness and Kurtosis Z-Score P-Value Z-Score P-Value Chi-Square P-Value -0.960 0.337 -0.083 0.934 0.928 0.629 ER2 -1.222 0.222 -0.282 0.778 1.573 0.455 ER3 -2.044 0.041 -1.759 0.079 7.273 0.026 ER4 -2.505 0.012 -2.269 0.023 11.422 0.003 CE1 -0.649 0.516 -1.173 0.241 1.798 0.407 CE2 -0.225 0.822 -0.540 0.589 0.342 0.843 CE3 -0.704 0.482 -0.612 0.540 0.870 0.647 CE4 -0.893 0.372 -1.230 0.219 2.310 0.315 IQ1 -0.845 0.398 -1.614 0.107 3.318 0.190 IQ2 -1.288 0.198 -0.324 0.746 1.764 0.414 IQ3 -0.385 0.700 -1.871 0.061 3.648 0.161 IQ4 -1.189 0.234 0.231 0.817 1.467 0.480 IQ5 -1.180 0.238 -0.091 0.927 1.401 0.496 IQ6 -0.720 0.472 -0.671 0.502 0.968 0.616 BS1 -1.288 0.198 -0.991 0.322 2.641 0.267 BS2 -0.959 0.337 -0.951 0.342 1.825 0.402 BS3 -1.379 0.168 -1.220 0.222 3.390 0.184 BS4 -1.573 0.116 -1.801 0.072 5.718 0.057 BT1 -1.102 0.270 -1.325 0.185 2.969 0.227 BT2 -0.753 0.452 -0.759 0.448 1.142 0.565 BT3 -0.983 0.326 -0.991 0.321 1.949 0.377 BT4 -1.127 0.260 -0.136 0.892 1.290 0.525 BA1 0.389 0.697 -1.008 0.313 1.168 0.558 BA2 0.997 0.319 -2.613 0.009 7.824 0.020 BA3 1.074 0.283 -2.767 0.006 8.810 0.012 BA4 0.171 0.864 -1.468 0.142 2.183 0.336 BA5 0.771 0.441 -2.674 0.007 7.746 0.021 PI1 -1.961 0.050 -1.074 0.283 4.999 0.082 PI2 -1.583 0.113 -0.636 0.525 2.912 0.233 PI3 -1.407 0.159 -0.144 0.886 2.000 0.368 PI4 -1.391 0.164 0.284 0.777 2.015 0.365 PD1 -0.625 0.532 -0.338 0.735 0.505 0.777 PD2 -0.498 0.619 -0.915 0.360 1.086 0.581 PD3 -1.363 0.173 -1.059 0.290 2.978 0.226 PD4 -1.026 0.305 -0.730 0.466 1.586 0.452 Relative Multivariate Kurtosis = 1.239 31 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 Table 3. Test of Multivariate Normality for Continuous Variables Test of Multivariate Normality for Continuous Variables Skewness Kurtosis Skewness and Kurtosis Value Z-Score P-Value Value Z-Score P-Value Chi-Square P-Value 253.687 44.799 0.000 1605.126 23.314 0.000 2550.499 0.000 Table 4. The test results offending estimates from this study Code Errorvar R2 ER1 0,45 0,38 ER2 0,34 0,53 ER3 0,58 0,31 ER4 0,76 0,17 CE1 0,67 0,27 CE2 0,31 0,64 CE3 0,42 0,49 CE4 0,74 0,25 IQ1 0,70 0,29 0,22 IQ2 0,68 IQ3 0,98 0,19 IQ4 0,47 0,27 0,28 IQ5 0,52 IQ6 0,71 0,10 BS1 0,44 0,44 BS2 0,27 0,63 BS3 0,36 0,44 BS4 0,51 0,41 BT1 0,33 0,63 BT2 0,15 0,81 BT3 0,39 0,52 BT4 0,24 0,66 BA1 0,40 0,58 BA2 0,48 0,57 BA3 0,47 0,60 BA4 0,27 0,74 BA5 0,49 0,55 PI1 0,51 0,35 PI2 0,40 0,36 PI3 0,31 0,54 PI4 0,24 0,63 PD1 0,30 0,60 PD2 0,31 0,66 PD3 0,43 0,51 PD4 0,38 0,51 Based on the hypothesis H2 test result, EWOM referral indirectly influences customer purchase decision. This finding supports the theory of reasoned action of Ajzen (1991). The theory stated that external factor does not directly influence people’s behavior. This finding also supports previous study of Jalilvand and Samiei (2012) that was conducted in automobile industry in Iran. The study found that searching activity of the online reviews builds customer’s interest in purchasing a product of certain brand in Instagram. 32 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 Table 5. Goodness of fit of CFA and Structural Model Indicator Results Standard 1092.23 (P = 0.0) Bergantung pada df (P>0.05) 1092.23:359 (3.04) 3:1 (3) Kline, 2005 RMSEA 0.06 ≤ 0.07 Steiger, 2007 GFI 0.96 ≥ 0.95 AGFI 0.96 ≥ 0.95 RMR 0.052 Kecil Tabachnik & Fidell, 2007 SRMR 0.062 ≤ 0.08 Hu & Bentler, 1999 NNFI 0.96 ≥ 0.95 CFI 0.96 ≥ 0.95 Chi-Square x 2 Relative x2 (x2/df) Source Table 6. Hypotheses tests based on the results of the structural model testing Hypothesis T-Value Significant/ Insignificant Conclusion H1: ER → PI 2.11 Significant Hypothesis Accepted H2: ER → PD 0.72 Not Significant Hypothesis Rejected H3: CE → BS 0.33 Not Significant Hypothesis Rejected H4: CE →PI 0.15 Not Significant Hypothesis Rejected H5: CE → PD 0.89 Not Significant Hypothesis Rejected H6: IQ → BS 6.38 Significant Hypothesis Accepted H7: IQ → BT 9.05 Significant Hypothesis Accepted H8: IQ → PD 0.22 Not Significant Hypothesis Rejected H9: BS → BA 2.87 Significant Hypothesis Accepted H10: BS → PI 2.83 Significant Hypothesis Accepted H11: BT → BA 1.48 Not Significant Hypothesis Rejected H12: BT → PI 3.14 Significant Hypothesis Accepted H13: BA → PD 3.83 Significant Hypothesis Accepted H14: PI → PD 4.37 Significant Hypothesis Accepted H2: CE-PD (rejected), H3: CE-BS (rejected) and H4: CE-PI (rejected). In this study, it can be observed that celebrity endorsement has no influence on brand satisfaction, purchase intention, nor purchase decision. Based on this study’s finding, looking at a trusted and attractive celebrity endorsing a product does not provide enough force for the invidial to build satisfaction, purchase intention or purchase decision. This finding has different result with marketer’s believe stated in Spry, Pappu and Cornwell’s (2009) study. Marketers believe that celebrity have significant role in improving marketing effectiveness, brand recall and recognition, as well as purchase intention and action of consumers. In addition, this study’s finding does not align with the previous study (Mukherjee, 2009) that stated 33 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 that celebrity endorsement is the winning formula for brand marketing and development. O’Mahony and Meenaghan (1997) stated that alignment between the celebrity image and the related brand is desired by consumers However, this study contradicts that phenomenon in the case Instagram case in Indonesia. H6: IQ-BS (accepted), H7:IQ-BT (accepted) and H8:IQ-PD (rejected). Siau and Shen (2003), in their study, developed a model of trust building in mobile commerce context and they included information quality as one of the component that affects customer trust to perform e-commerce activites. Meanwhile, Loiacono et al. (2002) found that information quality, combined with functional-fit-to-task, was one of the important factors that drive consumer to purchase a product from a website. Both studies show that information quality has correlation in customer trust and purchase decision. This study aligns with the previous study in term of brand trust; however, we found that in Instagram case in Indonesia, information quality has weak correlation with purchase decision which can be concluded that information quality does not influence customer purchase decision. As for brand satisfaction factor, some previous studies (Wen et al, 2008 and Park and Kim, 2008) found that information quality has a direct and positive impact on customer satisfaction. This study’s finding aligns with those studies. We find that information quality influences brand satisfaction. H9: BS-BA (accepted) and H10: BS-PI (accepted). As for hypotheses H9 and H10, the finding is consistent with Lesmana’s (2012) finding. This study and the previous study (Lesmana, 2012) both find that brand satisfaction influences positively to brand attachment. Besides trust, many studies in e-commerce found that customer satisfaction was the main factor that influences customer’s purchase intention. One of the studies is Adji and Semuel’s (2014) study that found there was significant correlation between trust and purchase intention. Although there were different indicators and object of study, both yielded the same result, i.e. the dimension of satisfaction and trust influences purchase intention. H11: BT-BA (rejected) and H12: BT-PI (accepted) The previous study of Lesmana (2012) found there was strong positive correlation between brand trust and brand attachment. However, the finding in this study is in contrast with his finding. Eventhough this study uses the same four evaluation indicators this study receives different result. In this study, we find that brand trust has weak positive correlation to brand attachment, hence we conclude that brand trust does not influence brand attachment. It is likely that the difference is because this study investigates Instagram while his study examined Twitter. The nature of Instagram and Twitter is different on how the way information is represented, delivered, taken into action and perceived as benefit to user. Twitter focuses on text based information while Instagram uses pictures as the main information. Meanwhile, brand trust is confirmed to have direct influence to user’s purchase intention. Many have believed that trust dimension is one of the main dimensions that have strong correlation to purchase intention; for example, Gefen’s (2000) study that discussed trust in online world. In tourism sector, Ponte et al. (2015) studied the impact of trust to customer purchase intention through travel website. H13: BA-PD (accepted) 34 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 The findings show that brand attachment influences purchase decision. Customer’s decision to buy a product is influenced by the degree of attachment toward the underlying brand. This finding supported the study of McAlexande (2003) and Thomson (2005) in Rekarti (2012). This finding also implies that brand attachment is an important factor that should be utilized by sellers who uses Instagram as it has direct effect on purchase decision. H14: PI-PD (accepted) This study found that there is strong correlation between purchase intention and purchase decision that purchase intention influences purchase decision. This finding is aligned with the previous studies that also used Instagram social media (Prabowo, 2013 & Sandrakh, 2013). 7.2. Managerial Implications The results show that eWOM referral has direct impact towards purchase intention while information quality has direct impact towards brand satisfaction and brand trust. These results could give directions towards online shops or companies which use Instagram as marketing media. First, since eWOM referral has direct impact towards purchase intention, companies should optimize the feature ‘comment’ in order to filter unnecessary or unfavorable comments. Thus, it is expected that Instagram users would get more concern and more positive feeling from others about a particular product that would lead to higher intention to buy. Second, companies should pay more attention towards figure captions in Instagram such that the completeness, conciseness, understandability and relevance of the captions could support proper information delivery towards the users so that they perceive the information as in good quality. From the hypotheses testing it can be inferred that captions with such qualities would likely have impact towards brand satisfaction and brand trust. 8. CONCLUSION This research aims to examine the impact of Instagram social media as a marketing media towards purchase decision. From 14 hypotheses, 8 were accepted and 6 were rejected. Thus, this reseach conforms that eWOM referral and information quality have indirect relation towards purchase decision. EWOM referral has relation towards purchase decision via purchase intention while information quality has relation towards purchase decision via brand satisfaction and via brand trust. Interestingly, celebrity endorsement is found not having impact towards purchase decision either directly or indirectly. It has no relation towards any brand relationship dimensions, purchase intention or purchase decision. Brand relationship dimensions namely brand satisfaction and brand trust have indirect relation with purchase decision. Brand satisfaction has indirect impact towards purchase decision via brand attachment and via purchase intention. Brand attachment and purchase intention has direct relation with purchase decision. Similarly, brand trust also has indirect impact towards purchase decision via purchase intention. 9. LIMITATIONS AND FUTURE RESEARCH This research could not get the list of Instagram users who follow at least one online shop account. The authors only got an estimation of Instagram users in Indonesia i.e., circa 18 million. Conceptually, the convenience sampling used in this research could not generalize finding in the samples towards its population. Thus, further research might be conducted for better generalization of sample data towards its population. In addition, as this research uses Instagram users’ point of view, a further research to examine companies’ perspective in using Instagram as its marketing media would complement this study result and thus provide a more complete elaboration on this topic. 35 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 REFERENCES Adiputra, L. K. (2013). Penggunaan Sistem Jual Beli Online dengan Menggunakan Pendekatan Social Commerce. Bandung: Universitas Pendidikan Indonesia. Adji, J., & Semuel, H. (2014). 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Pacific Business Review International, 6(11). 40 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 APPENDIX Indicator Code Description Get concern from others (Sari, 2012) ER1 Consumer receives forms of care, pride and satisfaction from other consumers about a product of a brand. Get positive feeling (Sari, 2012) ER2 Consumer receives positive feelings expressed by other consumers for a product of a brand. Economic incentive (Sari, 2012) ER3 Consumer receives an amount of information—related to discounts, promotions, and other information related to economic incentive—about a product of a brand that is expressed by other consumers. Platform assistance (Sari, 2012) ER4 EWOM is suitable as a medium for the implementation of social commerce and social media marketing of a product of a brand. EWOM REFERRAL Indicator Code Description CELEBRITY ENDORSEMENT Visibility (Dyah, 2014) CE1 Celebrity who becomes the brand model in the product image posted by a brand is popular. Credibility (Dyah, 2014) CE2 Consumer is confident of the celebrity who becomes the model of a product of a brand in the image posted by a brand. Attractiveness (Dyah, 2014) CE3 Celebrity who becomes the model of a product of a brand in the image posted by a brand is appealing. Product match up (Dyah, 2014) CE4 Celebritiy’s profile who becomes the model of a product of a brand matches the profile of the endorsed product. Indicator Code Description Completeness (DeLone and McLean, 2003) IQ1 Good information quality is provided so that product description in the caption of an image posted by a brand is complete Conciseness (DeLone and McLean, 2003) IQ2 Good information quality is provided so that product description in the caption of an image posted by a brand is concise Accuracy (DeLone and McLean, 2003) IQ3 Good information quality is provided so that hashtag used to complement the description of a product in an image posted by a brand is accurate Undestandbility (DeLone and McLean, 2003) IQ4 Good information quality is provided so that image posted by a brand to promote its product or brand image is easily understood Relevance (DeLone and McLean, 2003) IQ5 Good information quality is provided so that brand’s product description written in the image’s caption is highly relevant to the image posted by a brand Currency (DeLone and McLean, 2003) IQ6 Good information quality is provided so that the brand frequently posts images in one day INFORMATION QUALITY 41 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 Indicator Code Description Decision (Lesmana, 2012) BS1 Consumer is satified with the decision taken related to a brand Experience (Lesmana, 2012) BS2 Consumer has satisfying experience related to a brand Function (Lesmana, 2012) BS3 Consumer is satisfied with the utilization of media to promote the brand Service (Lesmana, 2012) BS4 Consumer is satisfied with the services provided by a brand BRAND SATISFACTION Indicator Code Description Delivery (Lesmana, 2012) BT1 Consumer trusts the information delivered by a brand Statement (Lesmana, 2012) BT2 Consumer trusts the statement given by a brand Action (Lesmana, 2012) BT3 Consumer trusts a brand’s action Benefit (Lesmana, 2012) BT4 Consumer trusts that the brand gives benefits to consumers BRAND TRUST Indicator Code Description Brand self-connection: Bond (Lesmana, 2012) BA1 There is a bond between consumer and brand Brand self-connection: Emotional (Lesmana, 2012) BA2 There is emotional bond between consumer and brand Brand prominence: Mind (Lesmana, 2012) BA3 The brand is prominent in consumer’s mind Brand prominence: Feel (Lesmana, 2012) BA4 The brand is prominent in consumer’s feeling Brand prominence: Memory (Lesmana, 2012) BA5 The brand is prominent in consumer’s memory BRAND ATTACHMENT Indicator Code Description Information seeking (Sandrakh, 2013) PI1 Consumer wants to find more information about a product of a brand as he/ she has intention to buy the product Intention to understand (Sandrakh, 2013) PI2 Consumer wants to understand more about a product of a brand as he/she has intention to buy the product Intention to try (Sandrakh, 2013) PI3 Consumer wants to try a product of a brand as he/she has intention to buy the product Intention to buy (Sandrakh, 2013) PI4 Consumer wants to buy a product of a brand PURCHASE INTENTION 42 Information Resources Management Journal Volume 30 • Issue 2 • April-June 2017 Indicator Code Description Think (Palagan, 2012) PD1 Consumer thinks deeply about his/her decision of buying a product of a brand Feel (Palagan, 2012) PD2 Consumer develops an emotional feeling in buying a product of a brand Distinguish (Palagan, 2012) PD3 Consumer distinguishes a product of a brand from other brands in his/her decision of buying the product Choose (Palagan, 2012) PD4 Consumer chooses a product of a brand from other brands in his/her decision of buying the product PURCHASE DECISION Randy Danniswara obtained his bachelor degree in Information Systems from the Faculty of Computer Science, Universitas Indonesia. He has interest on social media commerce. Puspa Indahati Sandhyaduhita is a lecturer at the Faculty of Computer Science, Universitas Indonesia. She received her master degree from TU Delft, the Netherlands. Her research interests include e-commerce, information systems, requirements engineering, business process modeling, enterprise architecture, enterprise resource planning, and supply chain management. Qorib Munajat is a lecturer at the Faculty of Computer Science, Universitas Indonesia. He received his master degree from University of Melbourne, majoring in Information Systems. His research interests are software engineering, enterprise systems, and enterprise architecture. 43