Who needs trust when you know everything? Dealing with information abundance on a consumer-review Web site
First Monday

>Who needs trust when you know everything? Dealing with information abundance on a
consumer-review Web site by Andrew Duffy

Ideas about trust have been based on information scarcity. To overcome the uncertainty associated with choice, people gather information; when that is not enough, they turn to trust in order to make a decision. Consumer-review Web sites offer information abundance, however, which demands a re-evaluation of the function of trust under such circumstances. This study uses a survey to investigate the role of trust in the traveller review site TripAdvisor. It uses five concept pairings — two measurements of experience using the site, two forms of uncertainty, two mechanisms of information-seeking, two forms of trust and two behavioural outcomes — to explore how trust operates amidst information abundance. It proposes that while consumer-review Web sites overcome primary uncertainty (risk of making a poor choice) by providing information, they produce a secondary uncertainty (inability to assess all options) based on concerns about processing the mass of information efficiently. This study finds that trust plays a role in reducing both primary and secondary uncertainty, but not in decision-making. It proposes that trust may be subsumed into information seeking on information-abundant consumer-review Web sites, and discusses implications for how trust is understood and what it means for effective reviewer sites.


Study context: OURS
Literature review and hypotheses
Data gathering
Conclusion, limitations and future research




When travellers need a hotel room, many consult peer review Web sites such as TripAdvisor, Booking.com or Agoda (Gretzel and Yoo, 2008; Jeacle and Carter, 2011; Ye, et al., 2011). They are popular, and TripAdvisor (2015a) claims 340 million unique visitors each month. Yet one concern in scholarly thought is why people trust such sites despite accusations that many reviews posted on them are fakes (Ayeh, et al., 2013; Filieri, et al., 2015). These accusations may be well-placed: Schuckert, et al. (2015) put the proportion of suspicious reviews as high as 20 percent, and TripAdvisor has had to remove the phrase ‘reviews you can trust’ from its U.K. site (Ayeh, et al., 2013b).

Why do people trust a site that is ostensibly so untrustworthy? To answer this question, this paper asks how trust functions on these Web sites where it has been so doubted, and where factors other than trust may explain site utility. To do this, I investigate how the largest travel peer review site, TripAdvisor, helps people choose a hotel; and the role of trust in their choice. I refer to such sites as OURS (online user review sites) as they are ‘ours’, made by and for us.

TripAdvisor’s power comes from the volume of information it carries (Surowiecki, 2005). Yet for all that, it still may not deliver the perfect hotel, because of the wealth of data. The abundant information on the site can overcome one form of uncertainty — not knowing enough to confidently choose a hotel. But it introduces a secondary uncertainty — how reliable are the reviews, how credible are the contributors (Racherla, et al., 2013, and how can one process so much information at all?

OURS help people overcome uncertainty by providing information. When faced with uncertainty, people gather data (Berger and Calabrese, 1975; Engel, et al., 1995); if that proves insufficient to make a confident choice, they turn to trust in order to drive the final decision (Mudambi and Schuff, 2010). So initially, uncertainty about hotel choice impels people on an information search using TripAdvisor (Hennig-Thurau and Walsh, 2003). In the past, information has been in short supply. This is not a problem with OURS. Quite the opposite. OURS approximate to a perfect information system in which all options are known and can be weighed. This brings the disadvantage of information overload rather than information poverty (Miller, 1956; Bergamaschi, et al., 2010). As a result, OURS’ profusion of information can induce a secondary uncertainty, first about the quality and origin of the reviews (Dellarocas, 2003), and second about the cognitive demands needed to sift through them all. To counter these, TripAdvisor provides information about the contributors, asserts that it removes fraudulent posts; and is searchable and simplifies choice by aggregating reviews into an overall score for each hotel (TripAdvisor, 2015b).

Using the site demands media literacy, defined as the ability to ‘access and process information from any form of transmission’; the key skill for an OURS is to filter the data into a useable amount [1]. TripAdvisor requires the literacy to assess the value, relevance and credibility of contributors, and to use site functionalities to reduce the number of reviews and hotels to a manageable amount. Even with such literacy, however, there may not be enough information to know for sure that reviews are credible, that the contributors posting reviews are honest, or that the system is reliable. In this case, once again the individual resorts to trust.

It is vital to understand how trust functions on OURS as information is increasingly being sought online from peers sharing their experience on such sites (Casaló, et al., 2011). OURS move power away from the authorities and into the hands of the individual, in the form of Web 2.0 collective intelligence (O’Reilly, 2005). The experiences of millions of amateurs replace the musings of a few experts (Jeacle and Carter, 2011) in what has been referred to as the ‘wisdom of crowds’ (Surowiecki, 2005). The primary uncertainty that TripAdvisor overcomes has been well explored (Jeacle and Carter, 2011; Papathanassis and Knolle, 2011; Vásquez, 2011; Jurca, et al., 2010). A clearer understanding of the secondary uncertainty would help theorise more completely the role of trust in OURS which are criticised for being untrustworthy and yet evidently have utility for hundreds of millions of travellers (Ayeh, et al., 2013b).

This paper examines trust on TripAdvisor by surveying regular users of the site (N=237) employing five concept pairings — two measurements of prior experience on the site, two forms of uncertainty, two mechanisms of information-seeking, two forms of trust and two behavioural outcomes. The background to the survey was interviews with 30 users of TripAdvisor, (female, 16; male, 14; ages 22–63, median 40; Western, 17; Asian, 13) to ascertain what they use the site for, and their feelings towards the site, the people writing on it, and its utility. Their most common motivation for accessing the site was to look for suitable hotels to stay in while overseas (23 responses), followed by looking for attractions in a destination (9). They were specifically motivated to access the site because it carried information by ordinary travellers like them, and people who had similar interests to them (21). They also used the site because it helped them get value for money (12), represented a wide variety of hotels (8) and offered more recent information than any guidebook (6). In terms of what they wanted to find about a hotel, they mentioned location most often (10), followed by cleanliness (6), and amenities, safety and service (3 each). Taken together they paint a picture of TripAdvisor users who value the opinions of people like them when choosing a hotel, and seek hotels in the ‘sweet spot’ where price and quality meet.

This paper describes the context of the study, followed by a review of the main concepts. These are linked to research questions and hypotheses, which leads to the survey instrument, the results section, and discussion of the principal question: What place does trust have on TripAdvisor, and is it needed for decision making?



Study context: OURS

With 340 million unique monthly visitors and 225 million reviews of five million hotels, restaurants and attractions, TripAdvisor is the largest travel OURS (TripAdvisor, 2015a). Travellers use it to get unvarnished opinions about places to stay, rather than relying on biased reports on a hotel’s or a tourist board’s Web site, in keeping with research that says we trust the opinions of other people more than marketing agencies (Dickinger, 2011; Papathanassis and Knolle, 2011). It is not alone and Booking.com and Agoda also allow travellers to share opinions. Some consider these more trustworthy as contributors must have booked through them to post a review, which does away with the fear of bogus postings that dogs TripAdvisor (e.g., O’Connor, 2010; Smith, 2011). TripAdvisor is the focus of this study as a proxy for all such OURS, although sites vary in what they offer and people may respond differently to them.



Literature review and hypotheses

The first variable was experience using the site. It was taken that the more successful experience a user had had in researching hotels on TripAdvisor, and the more successful they had been in choosing a hotel, the more likely they would be to trust the site. Thus experience would have an impact initially on the level of trust shown in the site, and subsequently on whether there was any need for trust when it came to making a booking. This led to the first hypothesis:

H1: The more a user has enjoyed successful experiences using TripAdvisor, the more likely they will be to trust it.

Uncertainty reduction. This paper takes its lead from a process of decision-making in conditions of information scarcity: uncertainty → information-seeking → trust → decision. It measures three forms of primary uncertainty that could drive a consumer to TripAdvisor: a hotel might give poor value for money; the user might find time is wasted by choosing the wrong hotel; and the user might experience a lack of satisfaction if the hotel is not up to expectations. OURS bring secondary uncertainties, however, and these were also measured: the site may be risky because the information may be unreliable or written to deceive (Lee, 2014); and the surfeit of information may be difficult to process effectively. This led to the second hypothesis:

H2: The primary uncertainties of hotel selection are countered by information abundance on TripAdvisor, so secondary uncertainty will be more significant.

Functionalities and perceived homophily. TripAdvisor offers two information streams to overcome this secondary uncertainty: functional and social. Both help the traveller process abundant information by aggregating reviews into a ranking, and by identifying contributors whose reviews will be useful.

The first involves using the functionalities of the OURS which make it searchable, for example, or aggregate many reviews into a single score (Metzger, et al., 2010). One study identified 28 aspects that engender trust online, which include navigability, technology and presentation, or how effectively the visuals communicate the purpose of the site (Cheskin/Sapient, 1999). More recently, Sundar (2008) proposed the MAIN model where the mere presence of functionalities can help explain media credibility, based on an aspect’s value-adding function.

The social information stream involves identifying ‘perceived homophily’ (Lazarsfeld and Merton, 1954) which is where travellers identify a shared interest between themselves and a contributor (Brown, et al., 2007). Studies have considered the social aspect of travellers looking on OURS for experiences shared by likeminded people (Gretzel, et al., 2007).

Other research has found that users of OURS pay more attention to reviews written by people like them (Xie, et al., 2011; Racherla, et al., 2012). One exploratory study of five OURS users (Williams, et al., 2010) found that beside information about the hotel, they wanted information about the contributor’s qualifications, beliefs and expectations, in order to assess how relevant their opinions are. Another study (Ayeh, et al., 2013a) verified the role of perceived homophily in attitudes towards OURS, and found that it had a strong link to trustworthiness but no impact on behavioural intention.

Perceived homophily links with research into social influence (Cialdini, 2001; Wood, 2000), persuasion (Briñol and Petty, 2009), and social comparison theory (Festinger, 1954). This last centres on the idea that people want accurate evaluations of their opinions, and compare themselves with others to achieve this. Further, self-categorisation theory (Hogg, 2000) suggests that people identify personal similarity with others based on a prototypical group similarity, in which they assume that both they and the group share interests, beliefs and attitudes. Thus perceived homophily allows consumers assign themselves and contributors to a ‘group’, which is helpful for making swift judgments.

It also merges with functionalities as TripAdvisor allows users to search for reviews only by business travellers, couples or families, in order to read reviews by travellers with similar interests to their own. These two elements of Web 2.0 sites have been drawn together in scholarly thought: Bruns [2] refers to the ‘networked technosocial environment’, while others have noted that ‘electronic networks make it easier to rely on the collective to assess information’ [3].

Trust. As noted earlier, uncertainty is countered first by gathering more information; when that is exhausted, people turn to trust. Trust helps people to co-operate and co-ordinate their efforts, and is associated with social connectedness (Putnam, 2000). Others have suggested that trust underpins social interaction and without it society would disintegrate (Simmel, 1978, cited in Meyerson, et al., 1996). Trust has been a persistent theme in scholarly thought on OURS, because it is so hard to know how credible they are. Contributors may have a grudge. They may in reality be the hoteliers praising themselves, or netizens or public relations companies paid by a hotel to post good reviews about themselves or bad reviews about their competitors (O’Connor, 2010; Smith, 2011; Racherla, et al., 2013). Yet despite the opportunity for deceit, people still trust them.

This article uses Mayer, et al.’s [4] definition of trust that is apt for OURS, as ‘the willingness of a party to be vulnerable to the actions of another party based on the expectation that the other party will perform a particular action important to the truster, irrespective of the ability to monitor or control that other party’. TripAdvisor users are vulnerable; they need contributors’ experience but cannot monitor it; they expect contributors to be helpful; but they cannot control them.

People trust other people, and they also trust systems. Personal trust rests on an emotional bond between people, helps communication and glues society together (Lewis and Weigert, 1985). For this study, this equates to contributor trust which is defined as the trust a person shows in an individual contributor, which can be based on what they write as well as factors such as their photograph and reputational markers which show how many hotels they have reviewed and how helpful their reviews have been judged (Xu, 2014).

Yet as people cannot gather enough information on everyone they engage with, they rely on trust in systems which rests on the idea that everything is in order. This was measured as site trust. It is defined as the level of trust a traveller shows in TripAdvisor itself and includes ‘belief that needed structural conditions are present ... to enhance the probability of achieving a successful outcome’ [5]. This led to the first research question (RQ1): What form of trust is most associated with secondary uncertainty in OURS? This paper suggests that contributor trust is based in part on the site’s credibility to weed out deceitful reviews; and that the site’s credibility rests in part on the honesty and trustworthiness of the individual contributors, leading to a hypothesis:

H3: Both forms of trust will be used to overcome uncertainty.

To explore this, I consider two linked dualities — perceived homophily and site functionalities, and contributor trust and site trust — and how each relates to uncertainty. Both contributor trust and site trust may be associated with perceived homophily, (McAllister, 1995; Montoya, et al., 2008) which led to the second research question (RQ2): To what extent is each form of trust related to perceived homophily or to the functionalities of the site? It seemed likely that contributor trust would be more associated with perceived homophily, leading to a hypothesis:

H4: Perceived homophily with contributors will show a positive association with contributor trust.

Yet other researchers have found that site functionalities are also associated with trust (McKnight, et al., 2002; Yoo, et al., 2009; Benlian and Hess, 2011), which leads to a further hypothesis:

H5: Site functionalities will show a positive association with site trust.

Behavioural intention. The final variable is behavioural intention, which is defined as an anticipated future behaviour and can be operationalised as the likelihood to act (Lam and Hsu, 2006). A third research question (RQ3) asked about the effect of uncertainty and both forms of trust on travellers’ behavioural intentions. Two intentions are used: one moves forward — to book a hotel after visiting TripAdvisor; the other moves back into the information-search process — to compare the site against other sources. The first suggested that uncertainty had been overcome sufficiently to move on. The second suggested that uncertainty had not been overcome. This led to a final hypothesis:

H6: Experience, perceived homophily and functionalities that limit a search will show positive associations with trusting intentions to book a hotel, but not with the non-trusting intention to compare information found on TripAdvisor against other sources.



Data gathering

For this study, a survey (Appendix) measured TripAdvisor users’ perceptions of the variables. It was pre-tested on 11 travel journalism students who were using TripAdvisor to plan an overseas visit, revised based on their feedback, and then distributed among 115 university students and their families, and 140 regular users using SurveyMonkey. Such a self-selecting sample brings an unpredictable bias (Bethlehem, 2009), so this is considered an exploratory study. Items for the survey used five-interval Likert scales and were adapted from previous studies to ensure validity.

The items for the site’s functionalities were adapted from Sanchez-Franco and Rondan-Cataluña (2010) (ease of use; navigability; control), and Bart, et al., (2005) (freshness of information; aggregation of reviews) as well as measures concerned with personalisation of searches and ease of comparing information. For perceived homophily, this study adapted Bart, et al.’s (2005) measures of community; and Casaló, et al.’s (2011) measures of similarity, shared interests and goals.

Scale items for contributor trust were based on Dickinger (2011) who analysed OURS contributors and tourism boards. The scale’s nine items measured perception of the reliability, honesty, good intention and competence of contributors. Site trust was based on a survey into Internet vendors by McKnight, et al. (2002), and contained nine items including whether the site was capable and would help travellers. Finally, Bart, et al. (2005) developed measures of behavioural intention which were adapted to include booking a hotel and comparing the site with other sources.

The uncertainty, trust, perceptual homophily and site functionality items were merged into composite scales after confirmatory factor analysis, where individual items were not included if they fell below the.50 benchmark (Hair, et al., 1998). Altogether 237 usable responses were collected: 58 percent of respondents were female, and over half were aged under 30; nearly three-quarters had been overseas four or fewer times in the previous year, while over 10 percent had travelled more than seven times; over one-third had used TripAdvisor more than 10 times in the previous year, although most had used it less often.




People arrive at TripAdvisor with both a need for information and experience using the site, so the first hypothesis concerned the impact of this experience. Respondents were mostly either heavy or light users of TripAdvisor: in the previous 12 months, 35.7 percent had visited the site more than 10 times, while 21.4 percent had used it 4–9 times, and 33.2 percent had used it between one and three times. Overall, they were pleased with their choice of hotel after using the site: happy/extremely happy, 57.9 percent; neutral, 38.7 percent, slightly/extremely unhappy, 2.9 percent. H1 proposed that users who had had successful experiences with the site would be more likely to trust it. This showed true for both contributor trust (β .32 p<.001) and site trust (β .38 p<.001); however, this weakened when primary uncertainty (that the site would not deliver) was taken into consideration; and disappeared altogether when other trust-inducing elements such as perceived homophily and site functionalities were included. This suggests that experience is a factor when accessing the site, but less so when actually using the site in which case the features of the site take over in contributing to trust.

Use of OURS stems from uncertainty, and the second hypothesis was that secondary uncertainty would be more significant for travellers while actually using the site. The data showed minimal associations with the primary uncertainty of choosing a hotel, so accessing TripAdvisor appears to overcome this uncertainty, supporting H2 (Tables 1 and 2). Secondary uncertainty was negatively associated with higher levels of contributor trust (β -.33 p<.001) and site trust (β -.39 p<.001), supporting H3 that both forms of trust will be used to counter secondary uncertainty.


Table 1: Antecedents of user trust in TripAdvisor contributors.
Note: *p<.05, **p<.01, ***p<.001
Contributor trustModel 1Model 2Model 3
Gender.11 .10 .07 
Experience with TripAdvisor-.08 -.13*-.16*
Satisfaction with TripAdvisor.32***.14*.08 
Primary uncertainty  0 -.01***
Secondary uncertainty  -.43***-.33***
Perceived homophily    .34***
Site functionalities    .13*
R-square.11 .24 .38 
Adjusted R-square.10 .22 .36 



Table 2: Antecedents of user trust in TripAdvisor as a Web site.
Note: *p<.05, **p<.01, ***p<.001
Site trustModel 1Model 2Model 3
Age-.05 -.06 -.08 
Gender.05 .04 .03 
Experience with TripAdvisor.06 0 -.05 
Satisfaction with TripAdvisor.38***.13 .06 
Primary uncertainty  .07 .04 
Secondary uncertainty  -.50***-.39***
Perceived homophily    .19**
Site functionalities    .24***
R-square.13 .30 .40 
Adjusted R-square.12 .28 .38 


RQ2 asked to what extent each form of trust is related to perceived homophily and site functionalities. It proposed that the former would be more associated with contributor trust (H4), and the latter more with site trust (H5). Not surprisingly, perceived homophily showed a positive association with contributor trust (β .34 p<.001) supporting H4 (Tables 1 and 2). This carried on to the intention to book a hotel (β .17 p<.005), suggesting that identification with other travellers impacts on successful booking (Table 3). Perceived homophily (β .19 p<.005) and site functionalities (β .24 p<.001) both contributed to site trust, although the latter showed no association with the intention to book a hotel. It was, however, weakly associated with the intention of comparing TripAdvisor against other sources (Table 4).

RQ3 asked about the effect of uncertainty and trust on behavioural intention, proposing that positive behaviour would be associated with the other variables while negative behaviour would not (H6). Secondary uncertainty remained a factor, positively associated with the intention to compare with other sources (β .23 p<.001) and a negative association with the intention to book a hotel (β -.19 p<.05).

The site does not overcome uncertainty, which remains a factor when it comes to behavioural intention. Trust, however, does not. Intention to book a hotel showed no significant association with trust, which suggests that TripAdvisor operates as a (near-) perfect information system in which all options can be adequately known (Miller, 1956; Bergamaschi, et al., 2010). This paper suggests that under such circumstances there is less need for trust to make a decision, and none is evident.


Table 3: Antecedents of behavioural intention to book a hotel after using TripAdvisor.
Note: *p<.05, **p<.01, ***p<.001
BI book a hotelModel 1Model 2Model 3Model 4
Gender.05 .04 .03 .03 
Experience with TripAdvisor0 -.03 -.06 -.05 
Satisfaction with TripAdvisor.53***.43***.39***.39***
Primary uncertainty  0 -.01 -.01 
Secondary uncertainty  -.24***-.18*-.19*
Perceived homophily    .18**.17**
Site functionalities    .11 .12 
Contributor trust      .61 
Site trust      -.75 
R-square.32 .37 .41 .41 
Adjusted R-square.31 .35 .39 .39 



Table 4: Antecedents of behavioural intention to compare TripAdvisor.
Note: *p<.05, **p<.01, ***p<.001
BI compare with other sourceModel 1Model 2Model 3Model 4
Age-.01 -.01 0 -.02 
Gender.07 .07 .07 .07 
Experience with TripAdvisor.02 .04 0 -.01 
Satisfaction with TripAdvisor-.02 .05 0 .01 
Primary uncertainty  -.09 -.11 -.11 
Secondary uncertainty  .16*.24**.23**
Perceived homophily    .14*.17*
Site functionalities    .16*.16*
Contributor trust      -.14 
Site trust      .10 
R-square.01 .03 .07 .08 
Adjusted R-square -.01 0 .04 .04 
F-change.32  2.37 6.0**1.19 





As travel OURS bypass traditional gatekeepers such as journalists and guidebooks, people take responsibility for the information they find. If they trust OURS more than they trust experts (Schmallegger and Carson, 2008; Gretzel and Yoo, 2008), it is important to assess what form this trust takes. This study looked at two measurements of experience using the site, two forms of uncertainty, two aspects of the Web site that people can use to help gather information, two forms of trust and two behavioural outcomes. Earlier research has looked at these elements independently. This paper’s contribution is to draw them together into one study to investigate the role of trust in ‘untrustworthy’ OURS.

Another contribution is to propose a secondary form of uncertainty inherent in the site, and which demands travellers use a combination of perceived homophily and functionalities to reduce the volume of information to a manageable amount, to counter the problem that more information can lead to worse decisions rather than better (Jacoby, et al., 1974; Chen, et al., 2009). It appears that accessing TripAdvisor eliminates the primary uncertainties of choosing a hotel badly by offering abundant information. While this surfeit of information causes a secondary uncertainty about the quality and processing of that information, it counters the primary, ignorance-based uncertainty.

During the information-seeking process, perceived homophily was associated with contributor trust, consistent with the idea that people trust others to whom they feel similar (Hogg, 2000). It also joined forces with site functionalities when it came to site trust. Homophily appears to be dominant in OURS use. This is explained by studies that show that recommendations from family and friends are persuasive, (Litvin, et al., 2008) suggesting that OURS can play a role comparable to such people.

The findings describe trust in TripAdvisor. People trusted contributors to be reliable, sincere and competent, but not to have a good understanding of hotels (see Appendix). They trusted that the site would be good at what it does and would do as it promises, which both show competence. The site was not expected to look out for individual travellers. Both forms of trust were associated with secondary uncertainty, so trust continues to be a factor there. But it receded into the background when it came to decision-making. This suggests that trust has performed its task of overcoming uncertainty and is no longer essential. Even so, uncertainty was still present for both behavioural intentions, and was countered by satisfactory previous experience using the site, alongside (variously) the skill to identify which reviewers are relevant, and the skills to use the site functionalities to reduce the abundance of information.

The role of trust may be connected to the context. When information is scarce, people gather as much as they can and then if it is inadequate they use trust (Lewis and Weigert, 1985). But when information is abundant, trust fulfils a different role. Rather than being the link between information-seeking and decision-making, it is used to assess information which consequently forms the bridge to decision-making.

The results suggest that trust becomes subsumed in the information search rather than consequential to it. A model of decision making in information-abundant contexts thus becomes: uncertainty → information search (+ trust) → decision. Rather than ‘I’m unsure because there is too little information, I’ll just have to trust,’ it becomes ‘I’m confident because I trust the information’.



Conclusion, limitations and future research

Trust has been likened to social glue, drawing people together. It has been called the chicken soup of the social sciences: no one is sure how it works, but it seems to do some good (Uslaner, 2002). Trust is founded on uncertainty, but what happens when uncertainty is removed? Is there consequently no need for trust? Does information take its place the new social glue? Or does the altruism that OURS represent — people sharing experience and opinions for no immediate benefit to themselves — become the new mechanism for social cohesion? Or does self-reliance come to the fore, trusting one’s own literacy in using OURS so that ‘determining trust, believability, and information bias — key elements of credibility — become critical as individuals process the information in their lives gleaned from digital media’ [6]. In such a case, the traditional trust model of reliance on others given inadequate information is replaced with a model of reliance on self, given abundant information by others. This opens up research into how information abundance on social media alters social relationships and the ‘glue’ of trust that binds society.

This paper contributes to the scholarship on the role of trust in OURS as they become significant forces in information-seeking that alter the landscape of whom and what is trusted. The principal question was what place does trust have on TripAdvisor, and does it drive behaviour? The study investigated how previous experience, site functionalities and perceived homophily on TripAdvisor affected trust and behavioural intention, in a world where ‘electronic networks make it easier to rely on the collective to assess information’ [7].

Trust was associated with both perceived homophily with contributors, and with site functionalities. It was also associated with the secondary uncertainty, which is endemic to the site. However, it is still not clear that trust has any significant effect on decision-making, coinciding with earlier studies (Ayeh, et al., 2013b) which also found that perceived homophily had a strong link to trustworthiness of contributors, but found no impact on behavioural intention.

This study has some limitations, as the sample may not represent the TripAdvisor population, and closer work with the organisation might elicit better. Previous studies have proposed many antecedents of trust, and this study could not include them all. But for research into OURS, this study suggests that the incorporation of perceived homophily and functionalities could be valuable for understanding how information is processed.

This study has suggested that OURS use massed information to reduce the initial role of trust in decision-making, and homophily and site functionalities to reduce the consequent problem of information overload. As a result, these two are yoked together, which raises the question of the relationship between contributor and system. Rankings are in part based on reviews, which would suggest contributor trust contributes to site trust. Yet when travellers consider an individual review for perceived homophily, they dis-embed that review from the system that leads to the ranking. This merits further study. This study also placed perceived homophily at the heart of OURS, putting the social at the forefront of social media. Meikle and Young [8] state that ‘with social media it is no longer always clear whether we are being addressed as “someone” or “everyone”.’ With such dubious personalisation in evidence, it seems that travellers seek to redress this balance to reclaim their own identity, and engage perceived homophily to transform the ‘everyone’ into ‘someone’. By seeking similarities with contributors, they materialise their own identity, making a bond based on trust.

This paper does not suggest that trust recedes into the background under all circumstances when people use an information-abundant OURS. Alongside experience, multiple factors will affect trust, which have not been accounted for here. Some may be associated with the individual’s motivation for visiting the site in the first place. For example, if they are selecting a hotel not just for themselves but for other travellers too, they may feel less confident in their decision-making and trust may become a bigger factor. This was alluded to by four subjects in the interviews. The amount of money spent on the hotel relative to the individual’s usual spend may also affect trust. When someone is ‘splashing out’ on a hotel for a special occasion (which frequently involves also considering someone else’s opinions) there is greater pressure to ‘get it right’ which may heighten feelings of uncertainty and subsequently demand more trust. In addition, the destination itself may raise the level of uncertainty — and hence trust — as an individual may feel less confident venturing into an unexplored country than when choosing a hotel in a familiar destination. Nevertheless, as an indicator of how an OURS could counter secondary uncertainty — fear that the OURS is not to be trusted, and fear that the wealth of information will be too much to process — this paper indicates some factors which can help.

While scholars have asked why people trust TripAdvisor (Ayeh, et al., 2013b; Filieri, et al., 2015), it may be better to ask how trust is a factor — or whether it is at all. There is merit in having trust recede into the background rather than dominating an online activity: it is abstract, hard to pin down and harder to control, so for OURS and commercially minded Web sites to take steps to counter users’ reliance on trust can be a benefit. As a common concern for online stores is a lack of trust that dissuades shoppers from purchasing (Ogonowski, et al., 2014), the observations here may offer some help. Technologically aggregated reviews by shoppers who are similar to the consumer reduce the need for anything as irrational and abstract as trust.

As a searchable, information-abundant resource, TripAdvisor may be sufficiently functional to fulfil people’s demands, so trust recedes — provided users have the skills, often based on successful previous experience — to utilise the site effectively. Site functionality aggregates reviews, and while users did not necessarily trust individual reviews, the volume and the potential for identifying the relevant ones based on perceived homophily counteracted any concerns. Many potentially inaccurate statements can be aggregated into a single statement that is accurate enough overcome uncertainty, bypass trust and drive behaviour.

Multiple contributors to OURS reduce the need to trust any single one of them. With a system set up to reassure people that dishonest reviews are mostly removed (TripAdvisor, 2015b), uncertainty diminishes and so does the need for trust. With search functions to limit the information, the secondary uncertainty from information overload is reduced. With perceived homophily evidently a feature of site usage, people feel confident that they get relevant information. These combine to validate information and overcome uncertainty to a point that trust recedes as a driver of action.

As trust implies uncertainty, this study leads to the implication that e-commerce sites and OURS will remove uncertainty and the need for trust if they offer more rather than less information, along with the option to search it both in functional (ranking and rating) and social (by contributor type or interest) terms. Bigger is better. As one ‘father’ of Web 2.0, Tim O’Reilly (2005), pointed out, ‘a key Web 2.0 principle: the service automatically gets better the more people use it.’ End of article


About the author

Andrew Duffy is Assistant Professor in the Wee Kim Wee School of Communication and Information at Nanyang Technological University in Singapore.
E-mail: duffy [at] ntu [dot] edu [dot] sg



1. Potter, 2014, p. 15.

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Appendix: Survey questions with means, SD and Cronbach’s α.
Experience using TripAdvisor  
How often have you used TripAdvisor?2.271.47
How happy are you with your choice of hotel from TripAdvisor?3.660.74
Primary uncertainty before using TripAdvisor
It is possible that a hotel I choose will not be good value for money3.780.86
It is possible that a hotel I choose will be a waste of my time3.291.02
It is possible that a hotel I choose will not provide personal satisfaction3.780.87
Secondary uncertainty before using TripAdvisor
There is too much uncertainty in choosing a hotel based on TripAdvisor2.680.94
Choosing a hotel based on TripAdvisor is risky.2.630.94
I feel safe choosing a hotel based on TripAdvisor (reverse coded)3.430.81
Site functionality
On the site everything is easy to understand3.840.63
I can find information easily on the site3.830.7
When I navigate round the site, I feel that I am in control3.650.69
Regular updates mean the information is fresh3.790.65
Aggregating the reviews into rankings makes it easier to choose a hotel3.890.77
I can personalise the site for my needs3.140.75
I can easily compare different hotels using the site3.710.82
Perceived homophily
I feel a sense of community with people on the site2.960.82
I can interact with people who have successfully used the site3.120.76
Other users and I share the same interests3.180.72
Other users and I behave in a similar way3.060.77
Other users and I share the same objectives3.450.68
The most relevant reviews are written by people who are similar to me3.430.86
The site clearly shows which reviews are most helpful3.410.81
Contributor trust
Contributors are likely to be reliable3.490.77
I do not doubt the honesty of contributors3.260.89
I can count on the contributors to be sincere3.420.79
I expect the contributors have good intentions3.620.72
I expect the contributors are well-meaning3.570.74
I expect the contributors have my interests at heart3.190.87
The contributors are competent information providers3.330.77
The contributors can accurately describe their stay3.450.78
The contributors know about staying in hotels3.40.75
Site trust
I am comfortable relying on TripAdvisor to meet its obligations3.680.65
I feel fine looking at TripAdvisor since it generally does as it says.3.770.55
I feel confident that I can rely on TripAdvisor to do its part when I go there.3.60.7
I feel that TripAdvisor would act in a traveler’s best interest.3.50.72
If a traveler needed help, TripAdvisor would do its best to help.3.250.79
TripAdvisor is interested in traveler well-being, not just its own well-being.3.330.72
In general, TripAdvisor is competent at helping travelers.3.710.64
TripAdvisor does a capable job at meeting traveler needs.3.710.63
I feel that TripAdvisor is good at what it does.3.840.62
Behavioral intention after visiting TripAdvisor  
I would book a hotel after using to the site3.510.89
I would go to another site to compare with TripAdvisor3.840.85



Editorial history

Received 11 November 2015; revised 16 May 2016; revised 24 May 2016; accepted 22 June 2016.

Copyright © 2016, First Monday.
Copyright © 2016, Andrew Duffy. All Rights Reserved.

Who needs trust when you know everything? Dealing with information abundance on a consumer-review Web site
by Andrew Duffy.
First Monday, Volume 21, Number 7 - 4 July 2016
doi: http://dx.doi.org/10.5210/fm.v21i7.6313

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