Measurement of eWOM Trust (eWOMTrus)

The questionnaire included several alternative means to measure consumer’s trust towards online reviews. First, eWOM trust was measured by a refined set of Likert-like statements which was subject to development in the course of this thesis (the eWT-S). Here, respondents were asked to indicate their level of personal agreement for 25 items measuring the diverse aspects of trust on a 7-point scale ranging from 0=”I strongly disagree” (“Ich stimme Uberhaupt nicht zu”) to 6=”I strongly agree” (“Ich stimme vollig zu”). Second, for testing convergence validity by means of a Multitrait-Multimethod (MTMM) matrix (Campbell & Fiske, 1959; Churchill, 1979), eWOM trust was also measured using semantic differential scales. In the absence of an established scale, the semantic differential scale was constructed by adopting the Likert statements developed in this research. For instance, the original Likert item “The information given in online customer reviews is credible” was altered to fit a uni-polar semantic differential scale where the participants had to indicate the presence or absence of a single attribute. Accordingly, respondents had to evaluate their perception of whether “The information given in online customer reviews is credible” or “The information given in online customer reviews is not credible” on a 7-Point rating scale. Third, eWOM trust was also quantified by using a non-diagnostic single item. Here, the participants had to give an answer to the question, “On a scale where 0 = “I don’t trust at all” and 6 = “I absolutely trust”, how much do you trust the information given in online customer reviews?” (“ Geben Sie auf bitte auf einer Skala von 0 (ich habe Uberhaupt kein Vertrauen) bis 6 (ich habe volliges Vertrauen) an, in wie weit Sie Online Kundenrezensionen im Allgemeinen vertrauen.”). This scale was adopted from Boush et al. (1993) and was used in its regular application in the market information context (e.g., Soh, 2007). Fourth, generalized trust in online customer reviews was finally also measured by a multi-item reflective measure (see Table 6).

Variable Label	Item	Source	Scale
Tr1	The information given in online customer reviews is trustworthy. Information in Online Kundenreze sind vertrauenswUrdig.	adopted from Soh (2007); new items	7-Point Likert Scale (0=”I stongly disagree’’/’’Ich stimme tiberhaupt nicht zu”, 6=”I strongly agree”/”Ich stimme vollig zu”)
Tr2	The information given in online customer reviews is reliable. Information in Online Kundenrezensionen sind zuverlassig.
Tr3	In general, I trust the information given in online customer reviews. Im Allgemeinen vertraue ich Informationen in Online Kundenrezensionen.
Tr4	It is safe to trust information given in online customer reviews. Es ist sicher, Informationen in Online Kundenrezensionen zu vertrauen.
Tr5	I have confidence in online customer reviews. Ich habe Zutrauen in Online Kundenrezensionen.

Measurement of Attitude towards Reviews in General (Rau)

The respondent’s general attitude towards eWOM was quantified with two alternative scale- types, namely a Likert-format scale and a semantic differential scale. This enabled the author to make an assessment of the construct’s discriminance in various ways, including the usage of an MTMM matrix. Given the absence of reliable and validated scales in the researched area, both scales were taken from prior research in the field of advertising, where the original scales and adaptations found regular application (e.g., Petrovici & Marinov, 2007; Tan & Chia, 2007). Minor changes had to be made to both scales in order to fit the research context. Table 7 shows the items being used to measure consumer attitude towards online reviews. The first RAtt scale, originally introduced by Pollay and Mittal (1993), consisted of seven Likert-format scale items which emphasized consumer considerations in respect to the functional value of reviews, as well as the respondent’s emotional stance. All participants were asked to rate each of the seven statements on a seven-part scale ranging from 0 (“I strongly disagree”) to 6 (“I strongly agree”). The second scale was adapted from Olney et al. (1991) and included twelve semantic differential items. Persons’ responses were measured on a 7-point rating scale. Both scales are essentially striving to measure both the affective as well as cognitive aspect of an individual’s general attitude towards eWOM. While other scales in OCR research typically focus on either of them, this research assumes that potential similarities are highlighted more clearly with this approach.

Variable Label	Item	Source	Scale
AL1	Online customer reviews are essential. Online Rezensionen sind fur mich	adopted from Pollay and Mittal (1993)	7-Point Likert Scale (0=”I stongly disagree’’/’’Ich stimme tiberhaupt nicht zu”, 6=”I strongly agree”/”Ich stimme vdllig zu”)
AL2	Online customer reviews are a valuable source of information about products. Online Rezensionen sind eine wertvolle Quelle fur Produktinformationen.
AL3	In general, online customer reviews are misleading. Im Allgemeinen sind Online Rezensionen irrefUhrend. (R)
AL4	Online customer reviews tell me which products have the features I am looking for. Online Rezensionen sagen mir, welche Produkte das bieten, was ich suche.
AL5	In general, online customer reviews present a true picture of the product discussed. Im Allgemeinen zeigen Online Rezensionen ein wahres Bild des Produkts.
AL6	Overall, I consider online customer reviews a good thing. Ich halte Online Rezensionen fur eine gute Sache.
AL7	My general opinion of online customer reviews is unfavourable. Meine allgemeine Einstellung gegenuber Online Rezensionen ist negativ. (R)

Variable Label	Item	Source	Scale
AS1	Overall, online customer reviews are unpleasant - pleasant Online Rezennionen sind im Allgemeinen unangenehm - angenehm	adopted from Olney et al. (1991)	7-Point Semantic Differential Scale
AS2	fun to read - not fun to read lustig zu lessen - nicht lustig zu lessen (R)
AS3	not entertaining - entertaining nicht unterhaltsam — unterhaltsam
AS4	enjoyable - not enjoyable amiaant — nicht amustant (R)
AS5	important - not important wichtig — unwichtig (R)
AS6	informative - uninformative informativ — nicht informativ (R)
AS7	helpful - not helpful hilfreich — nicht hilfreich (R)
AS8	useful - not useful nutzlich — nicht nutzlich (R)
AS9	makes me curious - don’t make me curious macht mich neugierig — macht mich nicht neugierig (R)
AS10	not boring - boring nicht langweilig — langweilig (R)
AS11	interesting - not interesting interessant — nicht interessant (R)
AS12	keep my attention - don’t keep my attention haben meine Aufmerksamkeit — haben nicht meine Aufmerksamkeit (R)

Similarly to review attitude, respondents’ opinions concerning the general credibility of eWOM was measured with two maximally different scales: a Likert-format scale and a semantic differential scale. Here, participants were asked to answer a series of questions, including five 7-Point Likert format statements derived from the research of Boush et al. (1994) and a set of seven semantic differential format questions adapted from Beltramini and Evans (1985). Both scales are well established in advertising research and only needed slight adaptation to fit the current context. They measure a uni-dimensional construct that may also be called eWOM believability or honesty. Table 8 includes the items used to quantify generalized review credibility.

Table 8: Measures of Review Credibility

Variable Label	Item	Source	Scale
CL1	Online customer reviews tell the truth. Online Rezensionen sagen die Wahrheit.	adopted from Boush et al. (1994)	7-Point Likert Scale (0=”I stongly disagree’’/’’Ich stimme tiberhaupt nicht zu”, 6=”I strongly agree”/”Ich stimme vollig zu”)
CL2	I can believe what people write in reviews. Ich glaube was Konsumenten in Online Rezensionen schreiben.
CL3	The products recommended in online customer reviews are always the best products to buy. Die in Online Rezensionen empfohlenen Produkte sind auch diejenigen, die man kaufen sollte.
CL4	I can depend on getting the truth from most online customer reviews. Ich kann mich darauf verlassen, dass ich die Wahrheit in den moisten Rezensionen erfahre.
CL5	If a customer review were not true, it would not have been written. Es warden niemals unwahre Behauptungen in Rezensionen aufgestellt.

Variable Label	Item	Source	Scale
CS1	Overall, online customer reviews are trustworthy - untrustworthy Online Rezennionen sind im Allgemeinen nicht vertrauenswurdig - vert	adopted from Beltramini and Evans (1985)	7-Point Semantic Differential Scale
CS2	convincing - not convincing uberzeugend — nicht uberzeugend (R)
CS3	not credible - credible unglaubwurdig - glaubwilrdig
CS4	reasonable - unreasonable vernunfigt — unvernunftig (R)
CS5	unquestionable - questionable unstrittig — fragwurdig (R)
CS6	authentic - not authentic echt - unecht (R)
CS7	dishonest - honest unehrlich - ehrlich

The questionnaire also included the possibility to measure respondents’ attitude towards the credibility of review creators. Reviewer credibility was measured with nine items adapted from the established scale proposed by Ohanian (1991) on a 7-Point semantic differential scale. Ohanian’s scale was previously used to quantify credibility in the context of OCR (e.g., Dou et al., 2012). The scale assesses the two basic components of source credibility regularly identified in literature: reviewer expertise and reviewer trustworthiness. Table 9 presents the items included in the questionnaire.

Table 9: Measures of Reviewer Credibility

Variable Label	Item	Source	Scale
SCI	Consumer writing online reviews are undependable - dependable Konsumenten, die Rezensionen online verfassen sind nicht verlasslich - ver	adopted from Ohanian (1991)	7-Point Semantic Differential Scale
SC2	dishonest - honest unehrlich - ehrlich
SC3	unreliable - reliable nicht zuverlassig - zuverlassig
SC4	sincere - insincere aufrichtig — nicht aufrichtig (R)
SC5	untrustworthy - trustworthy nicht enstrauenswurdtg -
SC6	inexperienced - experienced unerfahren - erfahren
SC7	knowledgeable - unknowledgeable wissend - unwissend (R)
SC8	qualified - unqualified qualifiziert — unqualifiziert (R)
SC9	unskilled - skilled nicht sachkundig - sachkundig

Another important antecedent of eWOM trust is distrust in online reviewers in general. Attempts to operationalize the distrust construct are extremely rare in other trust contexts, and non-existing in the eWOM context. However, based on the conceptualization earlier advanced in this thesis, the author is confident that an adopted version of the scale introduced by Boush et al. (1994) captures the nature of the distrust construct quite reasonably. Therefore, the respondents were asked to indicate their personal level of distrust towards the motives of reviewers and recommenders on a set of four 7-Point Likert format statements (see Table 10). The scale mainly captures the extent to which eWOM recipients think that reviewers typically intend to manipulate them and their purchasing decisions.

Table 10: Measures of Distrust in Online Reviewers‘ Motives

Variable Label	Item	Source	Scale
SD1	Online reviewers care more about getting you to buy things than what is good for you. Online Rezensenten wollen eher bringen bestimmte Dinge zu als Konsumenten gut zu informieren.	adopted from Boush et al. (1994)	7-Point Likert Scale (0=”I stongly disagree”’/’’Ich stimme tiberhaupt nicht zu”, 6=”I strongly agree”/”Ich stimme vdllig zu”)
SD2	I often notice tricks that online reviewers play to get me to buy something. Ich bemerke oft Trick von Online Rezensenten, die mich zu einem Kauf animieren wollen.
SD3	Online customer reviews try to make people buy things they don’t really need. Online Rezensionen sollen Konsumenten dazu veranlassen Dinge zu kaufen, die sie eigentlich nicht brauchen.
SD4	Online customer reviews are different from other product information on the Internet in the way they try to influence you. Online Rezensionen sind anders als ubrige Produktinformatiionen im Internet da sie versuchen den Konsumenten stark zu manipulieren.

For measuring the respondents’ different forms of review usage, they were asked to complete a set of six 7-Point statements. The rating scales were anchored from 0 (“never”) to 6 (“always”) and included items concerning the dependence on reviews for important purchasing decisions, actual purchase influence and eWOM approaching behaviour (e.g., adoption, persuasion), but also behaviours such as the respondents’ own WOM engagement. All measures were adapted from a variety of established scales, including the work of Obermiller and Spangenberg (1998), Park and Lee (200), Sharvitt et al. (1998), Chu and Kim (2011), and Bailey (2005). Table 11 presents the items used to quantify general review usage.

Table 11: Measures of Online Review Usage

Variable Label	Item	Source	Scale
RU1	I use information from online customer reviews for important purchase decisions. Ich verwende Informationen von Online Rezensionen, um wichtige Kaufentscheidungen zu treffen.	adopted from Obermiller and Spangenberg (1998); Park and Lee (2009); Sharvitt et al. (1998); Chu and Kim (2011); Bailey (2005)	7-Point Likert Scale (0=”never”/”niemals”, 6=”always^,7”immer”)
RU2	I am influenced by online customer reviews when I choose a product. Ich werde von Online beeinflusst, wenn ich Produkte im Internet wahle.
RU3	I rely on online customer reviews when I purchase products. Ich verlasse mich auf Online Rezensionen, wenn ich Produkte im Internet kaufe.
RU4	Online customer reviews crucially affect my choice of products. Online Rezensionen bee meine Produktwahl wesentlich.
RU5	I like to pass along interesting information from online customer reviews to others. Ich gebe gerne interessante Informationen von Online Rezensionen an andere welter.
RU6	I visit product review websites prior to online purchases. Ich besuche ein Online Bewertungsportal bevor ich ein neues Produkt kaufe.

General review avoidance was assessed by presenting all participants a series of five statements, inviting the respondent to answer them on a rating scale ranging from 0 (“never”) to 6 (“always”). All items were adapted from the scales advanced by Obermiller and Spangenberg (1998), Speck and Elliott (1997), and Park et al. (2007). The items include active avoidance behaviour, as well as mental resistance expressions. Table 12 lists the items used to measure review avoidance.

Table 12: Measures of Online Review Avoidance

Variable Label	Item	Source	Scale
RA1	I avoid reading online customer reviews. Ich vermeide es, Online zu lesen.	adopted from Obermiller and Spangenberg (1998); Speck and Elliott (1997); Park et al. (2007)	7-Point Likert Scale (0-’never”/ ”niemals”, 6=”always”/”immer”)
RA2	I find online customer reviews irritating as the information provided is misleading and unreliable. Wenn ich Online Rezensionen betrachte, finde ich diese irritierend well sie irrefuhrend und unzuverlassig sind.
RA3	When I buy a product online, reading the reviews presented on the website impose a burden on me. Wenn ich online ein Produkt kaufe, stellt das Lesen von Online Rezensionen fur mich eine Last dar.
RA4	When I buy a product online, reading the reviews presented on the website irritates me. Wenn ich online ein Produkt kaufe, es mich, wenn ich Online Rezensionen lese.

The review involvement measures were adapted from the established work of Zaichkowsky (1994). Every participant had to indicate his/her personal involvement with online customer reviews and recommendations on this 9-item 7-Point semantic differential scale (see Table 13).

Table 13: Measures of Review Involvement

Variable Label	Item	Source	Scale
RI1	Online customer reviews are important - unimportant Fur mich sind Online Ku wichtig - unwichtig (R)	adopted from Zaichkowsky (1994)	7-Point Semantic Differential Scale
RI2	boring - interesting langweilig - interessant
RI3	relevant - irrelevant relevant — irrelevant (R)
RI4	exciting - unexciting aufregend — nicht aufregend (R)
RI5	mean nothing - mean a lot to me bedeuten mir nichts — bedeuten mir viel
RI6	appealing - unappealing ansprechend — nicht ansprechend (R)
RI7	fascinating - mundane faszinierend — banal (R)
RI8	worthless - valuable wertlos — wertvoll
RI9	not needed - needed von mir gewollt — von mir nicht gewollt (R)

As this research intended to assess the impact of disposition to trust on the tendency to trust eWOM, the personality trait construct was operationalized in the questionnaire with a set of nine 7-Point Likert statements ranging from 0 (“I strongly disagree”) to 6 (“I strongly agree”). The items were taken from McKnight et al. (2002a), as well as Gefen (2000), and aimed to quantify the respondents’ general faith in humanity as well as their trusting stance. Table 14 presents these items.

Table 14: Measures of Disposition to Trust

Variable Label	Item	Source	Scale
DPI	The typical person is sincerely concerned about the problems of others. Menschen sind normalerweise ermthaft um die Probleme anderer besorgt.	McKnight et al. (2002a)	7-Point Likert Scale (0=”I stongly disagree”/’’Ich stimme tiberhaupt nicht zu”, 6=”I strongly agree”/”Ich stimme vdllig zu”)
DP2	Most of the time, people care enough to try to be helpful, rather than just looking out for themselves. Meistens versuchen Menschen anderen zu helfen, anstatt sich nur um sich selbst zu kummern.
DP3	In general, most folks keep their promises. Im Allgemeinen erfullen die moisten Menschen ihre Versprechen.
DP4	Most people are honest in their dealings with others. Die meisten Menschen sind im Umgang mit anderen ehrlich.
DP5	I usually trust people until they give me a reason not to trust them. Ich vertraue Menschen normalerweise bis sie mir Grund geben dies nicht mehr zu tun.
DP6	I generally give people the benefit of the doubt when I first meet them. Wenn ich jemanden zum ersten Mai treffe, glaube ich ihm/ihr furs Erste.
DP7	My typical approach is to trust new acquaintances until they prove I should not trust them. Es ist meine Einstellung neuen Bekannten zu vertrauen bis ich einen Grund habe, dies nicht mehr zu tun.
DP8	I generally trust other people. Im Allgemeinen vertraue ich anderen Menschen.	Gefen (2000)
DP9	I tend to count upon other people. Ich neige dazu, mich auf andere zu verlassen.	Gefen (2000)

Table 15 and 16 show the items used to measure participants’ experience with the Internet in general and particularly with online reviews. The statements include a variety of active and passive behaviours and were all taken from scales used in prior research.

Table 15: Measures of Review Experience

Variable Label	Item	Source	Scale
RE1	I read reviews written by fellow shoppers. Ich lese Online Rezensionen von anderen Konsumenten.	Park and Lee (2009)	7-Point Likert Scale (0-’never”/ ”niemals”, 6=”always”/”immer”)
RE2	I search customer reviews on the Internet. Ich suche nach Kundenrezensionen im Internet.
RE3	I refer to online customer reviews whenever I need information on companies or goods. Ich besuche Online Rezensionen, wenn ich Informationen tiber Produkte oder Unternehmen benotige.
RE4A	I write down online reviews by myself. Ich schreibe selbst Online Rezensionen	Park et al. (2011)
RE5	I read online customer reviews when I was shopping. Ich lese Online Rezensionen bevor ich ein neues Produkt im Internet kaufe.	Park et al. (2011)

Table 16: Measures of Internet Experience

Variable Label	Item	Source	Scale
IE1	I have been using the Internet for ... Ich verwende das Internet seit ...	Corbitt et al. (2003)	(less than 1 year / between 1 and 2 years / between 2 and 3 years/ between 3 and 5 years / 5 years or more)
IE2	I use the Internet approximately ... Ich verwende das Internet durchschnittlich ...	Corbitt et al. (2003)	(Less than 1h per week / between 1 and 3h per week / between 3 and 10h per week / between 10 and 20h per week/more than 20h per week)
IE3	How often do you research products/services on the Internet that you are interested in buying? Wie oft suchen Sie im Internet Informationen uber Produkte, die Sie eventuell gerne kaufen mochten?	adopted from Murphy and Tocher (2011)	(never / once a year / once a month / several times a month / several times a week / almost every day)
IE4	Total number of online purchase during the last 3 months ... Wieviele Einkaufe haben Sie in den letzten 3 Monaten online getatigt?	adopted from Lee et al. (2011)	(0 / 1 / 2-5 / 6-10 / 11 or more)
IE5	How often do you read online customer reviews? Wie oft lessen Sie Online Kundenrezensionen?	adopted from Murphy and Tocher (2011)	(never / once a year / once a month / several times a month / several times a week / almost every day)