The Impact of Source Reputation on Inferences About Unadvertised Attributes

ABSTRACT - This study examines the impact that the reputation of a manufacturer or retailer has on the inferences and evaluations a consumer will make about a partially described product in an ad. It is hypothesized that such inferences about missing attribute information may be influenced by the attributions consumers make in determining why such information was omitted in the first place. Experimental results support this attribution-inference link, showing it to be strongest when the omitted or nondisclosed attribute covaries highly with existing attribute information about the product.

Citation:

Brian Wansink (1989) ,"The Impact of Source Reputation on Inferences About Unadvertised Attributes", in NA - Advances in Consumer Research Volume 16, eds. Thomas K. Srull, Provo, UT : Association for Consumer Research, Pages: 399-406.

Advances in Consumer Research Volume 16, 1989      Pages 399-406

THE IMPACT OF SOURCE REPUTATION ON INFERENCES ABOUT UNADVERTISED ATTRIBUTES

Brian Wansink, Stanford University

ABSTRACT -

This study examines the impact that the reputation of a manufacturer or retailer has on the inferences and evaluations a consumer will make about a partially described product in an ad. It is hypothesized that such inferences about missing attribute information may be influenced by the attributions consumers make in determining why such information was omitted in the first place. Experimental results support this attribution-inference link, showing it to be strongest when the omitted or nondisclosed attribute covaries highly with existing attribute information about the product.

INTRODUCTION

Imagine an audio enthusiast who is very concerned about the sound quality of the next video cassette recorder (VCR) she will buy. When an advertisement for a particular VCR fails to mention anything about the machine's sound quality, what assumption or inference will she make? In what ways will this assumption or inference be contingent on the reputation of the store selling the VCR or on the reputation of the manufacturer making it?

Inferences about important attributes (such as sound quality) that have been omitted from an advertisement or package label can significantly impact an individual's evaluation and choice of a product (Ford and Smith 1987). To a large degree, consumers make inferences based upon their knowledge of a product category (Meyer 1981) and based upon their knowledge of the specific attributes under consideration (Huber and McCann 1982). In this paper, it is argued that inferences can also be based upon the reputation of whoever manufactures or sells the product. Specifically, the following two questions will be addressed: 1) Given that inferences can occur, by what process does a source's (i.e., manufacturer's or retailer's) reputation influence the inferences made about an omitted product attribute? 2) Under what circumstances will a source's reputation have the most favorable impact on such inferences and evaluations?

Antecedents of Inferences: Motivation and Ability

Consumers do not always consider omitted or unavailable attribute information in their decisions. Such omitted information will obviously not stimulate inference-making unless it is salient to a consumer (Huber and McCann 1982). In some cases, a particular attribute could be salient because of its personal relevance or importance to the individual (e.g., sound quality is very important to an audiophile). In other cases, an attribute can be cued to salience through an ad or product label for a competing product, thereby stimulating cross-brand examination.

Provided that such omitted attribute information is salient, Simmons (1988) suggests that inferences will be made 1) if an individual has the experience and ability to make them, and 2) if doing so might enable him or her to make a better decision. In general, it appears that if an individual has the ability and the motivation to make such inferences about missing, salient attribute information -- or "target traits" -- he or she will do so. These preconditions indicate that such inference-making occurs in situations of high involvement. When consumers are less involved with a choice, they tend to simply lower their general evaluation of a product in lieu of making any inferences about omitted information (Simmons 1988).

This research focuses on what happens in those instances when consumers are highly involved with inference-making. When such is the case, two types of information are hypothesized to have an impact on inferences: product-related information and source-related information

Product-Related and Source-Related Cues

Much of the past research on inference-making has addressed the ways in which inferences about target traits are influenced by the other attributes the product possesses (Johnson and Levin 1985) or by how these inferences are affected by the consumer's general expectations for the product and product category (Meyer 1981). Such product-related cues can be seen as information that is inherent or related to the particular product or product category under consideration. For instance, if a person were concerned about the durability of an automobile he was shopping for, he might consider product category cues, such as the general durability of all automobiles, or he might also seek out product-specific cues, such as a particular automobile's warranty, service record, or other related features.

In contrast, source-related cues -- such as an automobile's manufacturer -- are external to the tangible, "nuts and bolts" of a product, but they are also thought to influence a consumer's inference about a particular target trait under consideration. A noncredible source, for instance, can legitimately encourage consumers to discount whatever information is presented in an advertisement (Sternthal, Phillips, and Dholakia 1978). In an analogous way, a credible or attractive source might be able to either directly discourage such discounting or to overcompensate for it with "halo effects" (Hovland and Weiss 1952). Additionally a source might also have an indirect impact on inferences depending upon what attributions a consumer makes as to why a source may have omitted certain target trait information. Such attributions about why this target trait is missing are thought to be clearly related to a consumer's perceived reputation of the source. Though there are many dimensions to a source's "reputation," one particular aspect of it -- the source's customer orientation -- will be examined in this study.

Customer Orientation

A business's customer orientation represents the degree to which a business is committed to providing customer satisfaction and establishing mutually beneficial, long-term relationships with its customers (Kotler 1980). In the case of a product manufacturer, a positive customer orientation would be evident in a manufacturer who is sincerely committed to satisfying customers and is not preoccupied with simply "selling at all costs.". A customer orientation of a manufacturer could be related to the perception of the honesty and sincerity they display through their advertisements, or by the degree to which they appear willing to accommodate the interests of their customers (Bagozzi 1985).

In the case of retail stores, customer orientation is related to the store's reputation, which is composed of the "attitude" and "knowledge" of the sales force and the store's policy regarding honesty and fairness in dealing with returns and exchange (Berry 1969). A customer's perception of these factors is likely to be based upon a store's history, its "word-of-mouth" reputation, and through any stereotypes related to the particular type of store it is (Dunn and Bradstreet. 1970).

CONCEPTUAL DEVELOPMENT

Source Attributions and Missing Information

Product information that appears in an advertisement may be a biased representation of the product since the advertiser allows consumers to see only that information which it wants them to see. When nothing is mentioned about an attribute -- or "target trait" -- that is important to a particular consumer (such as "sound quality"), he or she can either make favorable inferences about the target trait, unfavorable inferences, or no inferences. The question remains, when a consumer is highly involved in an evaluation and inferences are made, what determines whether those inferences will be favorable or unfavorable?

Research dealing with attribution theory -specifically correspondence theory (Jones and Davis 1965) -- provides some insight: If a consumer can think of an unfavorable reason why a certain target trait has been omitted from a product's advertisement, his or her attitude toward that product may become less favorable. In essence, inferences about target traits (and the subsequent evaluation of the product) can be influenced by a consumer's thoughts and attributions as to why the source omitted such information.

There are two types of attributions a consumer could make in this situation: Internal attributions and external attributions (Kelley 1973). Internal attributions are made when a consumer believes that the target trait had been omitted because of an "internal disposition" of the source, such as dishonesty or manipulative less (Settle and Golden 1974). Such attributions are evident in statements such as "they didn't want to draw attention to its weaknesses" and "they didn't want to encourage comparison with other products." In general, internal attributions are likely to encourage a consumer to "assume the worse" about the target trait and to discount the advertised product (Calder and Burnkrant 1977). In effect, internal attributions reflect unfavorable attributions.

External attributions, on the other hand, attribute the omission of the target trait to nonmotivational reasons. These attributions are not based on a distrustful view of the source but are charitably attributed to external constraints (e.g., "there wasn't enough room for the information") or to external assumptions (e.g., "they assumed we could guess it," or "it was more important to include other information''). Since such external attributions encourage a consumer to conclude that such an omission was "out of the source's control," these attributions should be favorable ones. Under conditions of external attribution, omission of such target traits will be seen less as manipulative than as necessary.

Besides being influenced by the perceived motivations (or the customer orientation) of the source, these attributions are also affected by the values of other attributes which are included in the advertisement. If those attributes are perceived as unimportant or trivial, external attributions (regarding limited space, for instance) cannot reasonably be made. Assuming such attributes are not perceived as unimportant or trivial,

Hypothesis 1: A source with a positive customer orientation will elicit more favorable (and fewer unfavorable) attributions about why a target trait has been omitted from an ad than will a source with a negative customer orientation.

Source Attributions and Product Evaluation

When consumers make favorable or unfavorable attributions about a source's motivation in having omitted target trait information, these attributions could potentially bias or influence a consumer's overall evaluation of the product. Though people tend to discount or devalue nearly any alternative with omitted attribute information (Yates, Jagacinski and Farber 1978), a significant part of this discounting can be directly traced to the inferences a person makes about such omitted information (Levin, Johnson, and Farone, 1984). For this reason, if unfavorable attributions are made about why a target trait is missing, these attributions can lead to unfavorable inferences about the target trait, and such inferences could manifest themselves in an unfavorable evaluation of a product. Such a process should be magnified even further when a consumer believes the omitted information was intentionally omitted to enhance persuasiveness. Thus,

Hypothesis 2: Favorable (unfavorable) attributions as to why a target trait was omitted from an advertisement will be related to a favorable (unfavorable) evaluation of that product.

Source Reputation and Product Evaluation

The logical extension of the previous hypotheses (customer orientation affects attributions which then affect evaluations) is that the customer orientation of a source should influence evaluations about a partially described product. Indeed, a robust finding across much of the source credibility literature indicates that a person's attitude toward a source can be transferred or "referred" to a position the source might advocate (Hovland and Weiss 1952). In an analogous manner, when a consumer has strong perceptions of the customer orientation of a manufacturer or retailer, these perceptions could potentially bias a consumer's evaluation of the products advertised by that manufacturer or retailer. Therefore.

Hypothesis 3: A source with a positive customer orientation will be elicit more favorable evaluations of a partially described product than a source with a negative customer orientation.

When Source-Related Cues Meet Product-Related Cues

The preceding discussion of inferences has focused on source-related cues. Much of what is known about the inferencing process, however, deals instead with product-related cues. This body of research has shown that a person's inferences about a particular target trait are positively affected when the trait covaries with positive existing attributes (Johnson and Levin 1985; Ford and Smith 1987). For instance, people may infer quality from price, durability from weight, or cleaning ability from "sudsiness" because of their perceived ecological covariation.

Though these findings have been strong, these studies have ignored the reputation or the credibility of the source. Regardless of the value these findings have in furthering our understanding in non-advocacy situations, advertisers must constantly deal with issues of reputation and credibility. Because of this "real world" concern of how a source's reputation affects inferences, it is worthwhile to determine how reputation might interact with existing product information. It is not clear that direct inferences (e.g., quality from price, durability from weight, etc.) are "automatic" in those cases when the source is perceived as having a negative customer orientation and as being potentially manipulative. In such instances, unfavorable attributions as to why these target traits were omitted could lead a consumer to be more skeptical about the product and to generally discount both the message and any related inferences (Sternthal et al. 1978). If a consumer, for instance, assumes that a source will try to unfairly manipulate his or her impressions of the product, this could encourage wariness and a conservative evaluation of the product. In contrast, when such a source is perceived as having a more positive customer orientation, such concerns of being manipulated should be reduced, thereby allowing for these direct (and positive) inferences to be made more freely from any existing, covariant attributes. Though the previous hypothesis (H3) predicted customer orientation would have a general impact on evaluation, it appears that this impact will be mediated by whether this target trait covaries with existing attributes. Formally stated,

Hypothesis 4: The more covariant (up to a point) a target trait is with existing attribute information, the greater of an impact customer orientation will have on product evaluations.

Conversely, when the target trait does not covary with existing attribute information, the affect of customer orientation on a product's evaluation should be less pronounced. In such instances, final judgment about the product is likely to be suspended while a consumer searches for additional information about this target trait. In summary,

Hypothesis 5 The less covariant a target trait is with existing attribute information, the less of an impact customer orientation win have on product evaluations.

The basic relations expressed in the above hypotheses are indicated in the Attribution-Inference Model in Figure 1. Generally speaking, when consumers are cued to important attributes that have been omitted from an ad, their perception of the customer orientation of the manufacturer or retailer affects whether they will make favorable (external) or unfavorable (internal) attributions about why such information was omitted. These attributions are important since they influence the inferred value for the target trait which, in turn, directly affects the evaluation of the product. This relationship is especially strong when information about highly covariant attributes is salient. It is important to note that besides affecting target trait inferences directly, these existing attributes also help consumers determine "why" such a target trait may have been omitted. The value and importance of these attributes "signals" whether it is reasonable to make external (i.e., favorable) attributions.

METHODOLOGY

Design and Stimuli

This study was conducted with a 3 x 2 between-subject factorial experiment. Factor A was a three-level manipulation of the customer orientation of an information source ("positive," "negative," and control). Factor B manipulated the covariance of the cued missing attribute with existing attribute information (high covariance, r = .51; moderate covariance, r = .76).

Respondents consisted of 125 women who were support staff at Stanford University. They were randomly assigned to each of the six conditions and were processed in groups of approximately 20. For their participation in this and another study they were each paid five dollars and offered an opportunity to win a $100 lottery.

FIGURE 1

ATTRIBUTION-INFERENCE MODEL FOR MISSING TARGET TRAITS (TT)

The context of the experiment was one in which a hypothetical audio and video- store had placed an ad in a newspaper for a VCR it was selling. The ad included three of the VCR's attributes (picture sharpness, special features, and sound quality) as rated by Consumer Guide. This hypothetical but presumably objective rating source was used to reduce the probability that respondents would question the truth or falsity of this given attribute information.

The accompanying cover story manipulated the perceived customer orientation of the store by providing background information about how ownership changes had resulted in a recent increase (decrease) in customer loyalty due to an increase in customer satisfaction (dissatisfaction). In addition, a control group was tested where no information about customer satisfaction was provided.

Procedure and Manipulation Checks

Respondents were instructed to imagine that they were considering the purchase of a video tape recorder (VCR). Along with a hypothetical ad designed by "Team Audio and Video," they were given the instructions and background information which manipulated the perceived customer orientation of Team. After looking at the advertisement, subjects were asked for reasons why they believed a particular target trait -- two-year unlimited warranty (moderate covariance) or color quality (high covariance) -- was not mentioned in the ad. Following these thought protocols were specific questions which measured the product's perceived quality and the subject's estimated satisfaction with the product on a seven point scale. Additional questions were asked about VCR ownership and familiarity as well as measures of confidence in purchase situations.

A separate group of 39 subjects were used to provide a manipulation check on the three levels of customer orientation and on the two levels of attribute covariance. On a nine point scale, the warranty attribute (4.51; r = .51) was shown to be less covariant (p<.001) with existing information than was color quality (6.80; r = .76), and the manipulation check with customer orientation was also significant (P<-001)

Coding of Thought Verbalizations

Regardless of their treatment condition, most subjects provided cognitive responses which could be coded into at least one of twelve specific response categories. These twelve categories were collapsed into groups of "favorable" attributions (i.e., "no room for target trait," "there were more important things to include," etc.) and "unfavorable" attributions ("the attribute was poor," "they wanted to discourage comparison," etc.). Favorable (external) attributions implied that the business had omitted such information about the cued attribute for legitimate, non-manipulative reasons instead of intending to mislead potential customers. The two response categories on which the judges did not reach a clear consensus were dropped from the coding scheme.

The 22 subjects whose thought protocols included one or more favorable response about the missing attribute, were labeled as "favorable." Using the same procedure, 59 subjects were labeled as "unfavorable" and 44 as "neutral." Protocols were labeled "neutral" if they contained an unrelated response or if they contained an equal number of favorable and unfavorable responses (n = 7). Thought protocol coding was also performed by a second coder on a subset (54 percent) of the questionnaires, yielding a coding reliability of .892.

ANALYSIS AND RESULTS

Consistent with H1, respondents were likely to make favorable attributions about the omission of "color quality" information when they were in the positive customer orientation condition. For instance, they were more likely to innocuously infer that "there wasn't enough room in the ad for that information," or that "(Team) probably forgot to include it" (p < .05). In contrast, differences in attributions between the positive and negative customer orientation conditions were not made regarding the omission of the "two-year unlimited warranty." Despite the fact most respondents believed the product probably did not have a two-year unlimited warranty, it is interesting to note why they believed this. Respondents in the negative customer orientation (n = 59) condition were more likely to claim that such a warranty "would not be honored by the business" than were the subjects in the other two conditions (p < .05).

In general, these results provide support for the notion that the perceived customer orientation of a source can affect whether favorable or unfavorable attributions will be made as to why a target trait has been omitted (H1). Furthermore, the greatest occurrence of favorable attributions was in the high covariance ("color quality") condition, adding support to hypothesis (H4) that covariance has a mediating role in this Attribution-Inference Model.

As predicted in H2, attributions (positive, negative, neutral) as to why the target trait had been omitted proved to have a great impact both on measures of quality (F(2,12 I) = 3.62, p < .05) and on estimated satisfaction (F(2, 21) = 7.24, p < .01) after controlling for familiarity and ownership. Though it was thought that favorable and unfavorable attributions would both relate directly to the evaluation of the product (H2), only the unfavorable ones had this impact. Correlations between the number of unfavorable attributions and evaluations revealed a significant relationship for both estimated satisfaction (r = -.179; p < .01) and for quality (r = .159; p < .01). This indicated that negative attributions may hurt evaluations more strongly than positive ones improve them.

Support for the notion that a positive customer orientation will have a relatively stronger effect on product evaluations than a negative customer orientation (H3) was mixed, for the measurement of quality was significant (F(1,82) = 4.38, p > .05) while the measurement for estimated satisfaction was not (F(1,82) = 1.98 p > .10). As can be seen in Figures 2A and 2B, this effect of customer orientation on evaluation was most pronounced when the covariance of the target trait with existing attributes was high (H4) than when it was only moderate (H5). When such covariance was high ("color quality"), a t-test indicated a significant difference on the measurements of both quality and estimated satisfaction (p < .01 and p < .03). When the attribute was less covariant ("two-year unlimited warranty"), however, respondents provided nearly identical evaluations.

Though the focus of the hypothesized relations have centered around positive and negative customer orientation, these results also indicate that a positive customer orientation can also yield a better evaluation than a neutral customer orientation (under conditions of high covariance). This interaction between positive customer orientation and the control condition was significant for the measurement of estimated satisfaction (F(1,77) = 4.28, p < .05) and directional for that of quality (F(1,77) = 2.41, p > .10).

LIMITATIONS

As discussed earlier, attributions about a source and inferences about omitted information are not always made. Such processing is limited to those high involvement situations where a consumer has both the motivation and the ability to make them and when the source is seen as biased. In the context of this study, ability to respond was assumed (81 percent VCR ownership) while motivation and the reputation of the source were strongly manipulated. The results cannot, therefore, be generalized to low-involvement situations, or situations in which source reputation is not highly salient. In such cases, as noted previously, a consumer would be likely to simply discount his or her evaluation of the product under consideration.

An additional limitation results from different operationalizations of the two target traits. Whereas "color quality" and "two-year unlimited warranty" were originally believed to vary only to the degree of their covariance with existing attributes, it is now seen that the first represents a product dimension while the second may be viewed as more of a feature (Johnson and Kisielius 1985). In other words, "color quality" could be viewed as a continuous variable that every VCR has to some degree, whereas "two-year unlimited warranty" may merely represent a feature that the VCR either possesses or does not possess. In such a case, differences between positive and negative customer orientations could be naturally suppressed since few VCRs are likely to carry this specific feature. Although a perceived negative customer orientation generated more negative inferences than a positive orientation (p < .10), there were an insignificant number of positive inferences between the two. A stronger test of this Attribute-Inference Model would have been to have asked respondents about "the warranty" instead of making the target trait as specific as a "two-year unlimited warranty."

DISCUSSION AND FUTURE RESEARCH

In general, the results of this study provide support for the notion that the evaluation of a partially described product will be significantly affected by a consumer's perception of the source of this information. In particular, respondents were much more likely to make unfavorable attributions about why a target trait was missing from an advertisement when a retailer had a negative customer orientation than when it had a positive one. These attributions, especially the unfavorable ones, went on to influence product evaluations, having the greatest impact when salient attribute information highly covaried with the missing target trait. This suggests that inferences about target traits are more strongly influenced by a source's customer orientation the more strongly this target trait covaries with existing attributes. As mentioned earlier, this is thought to be because of the subject's greater skepticism and conservatism when uncertainty about a target trait is high (as is the case when there is no highly covariant information).

FIGURE 2A

MEAN VALUES FOR "ESTIMATED SATISFACTION"

FIGURE 2B

MEAN VALUES FOR "QUALITY"

Though this study suggests that a source's reputation has an impact on attributions and inferences, the greatest impact on these attributions and inferences still comes from covarying attributes. Evidently, "seeing is believing" as far as inferences are concerned. Basically, a positive customer orientation elicits favorable evaluations for a product only when such a business's ad contains attribute information which happens to highly covaries with whatever target trait the consumer considers important. If only moderately covarying (or noncovarying) information is provided in the ad, a positive customer orientation will be of little value in influencing attributions, inferences, or evaluations.

The time and space constraints in marketing communication contexts (advertising, package labeling, personal selling, etc.) force communicators to focus on certain product information at the expense of other information. Understanding the role of consumer attributions and inferences in such situations, helps suggest how messages can be most effectively presented, given these constraints. Specific variables of potential interest include the following:

Individual variables: Experts/ novices, searching/buying, high/low confidence.

Source variables: High/low customer orientation, advertising/personal selling, high/low purchase pressure (or time constraints).

Context variables: Comparative/ noncomparative environment, products/services, severe/nonsevere space constraints.

Attribute variables: Covarying/non-covarying, objective/subjective, highly/moderately important.

Given the important role of attributions and inferences in persuasion, it would seem that any theoretical and empirical contributions in these areas would serve to provide us with a more thorough understanding of consumer decision making in such pervasive conditions of missing.

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