Date of Award

Spring 2011

Document Type


Degree Name

Doctor of Philosophy (PhD)


Business Administration-Marketing

Committee Director

Kiran Karande

Committee Director

Mahesh Gopinath

Committee Member

Joan Mann


This dissertation investigates the effect of signal consistency/inconsistency and signal unexpectedness on a consumer's evaluation of a product. It consists of two studies. Study One examines the effect of signal consistency/inconsistency on product quality, where consistent signals are those of the same valance. Prior research has found that a positive cue not only was unable to improve product quality perception, but also had a negative effect on perceived quality when a positive cue was combined with a negative one. The results of Study One indicate that when signals are inconsistent, consumers engage in an attribution process to explain inconsistency. If consumers attribute inconsistency to persuasive motive, then perception of quality decreases. If no persuasive motive is perceived, then consumers tend to discount inconsistent signals and perceived product quality is not affected by those signals. Study One contributes to the literature in three ways. First, the study adds to our knowledge of multiple signals as it increases our understanding of the interaction among extrinsic cues, which is an under-researched area (Purohit and Srivastava 2001). Second, current literature provides adequate explanations of the disappearance of signals' effects on product quality perception; however, no explanation is available for the negative effect of signals on product quality perception, an effect documented by Boulding and Kirmani (1993). This study offers such explanation. Third, the study provides the first empirical examination of the effect of extrinsic cues on the use of persuasion knowledge. Study Two examines the effect of signal unexpectedness on perceived quality. In current literature, credibility is assumed to be based only on the existence of a bond of some kind (Boulding and Kirmani 1993). Using a reputable firm or manipulating a firm's reputation was assumed by previous research to be the primary way to obtain signal credibility (Boulding and Kirmani 1993; Price and Dawar 2002; Agarwal and Teas 2001; Miyazaki, Grewal, and Goodstein 2005). Current findings, therefore, cannot be generalized to new firms that have not established a reputation of any kind. To overcome the problem of basing signals' credibility solely on a firm's reputation, Study Two examines the effect of some signals on the credibility and effectiveness of other signals. The results of Study Two indicate that when faced with a diagnostic cue with ambiguous credibility, consumers use other cues to reach a conclusion about diagnostic cue credibility. When the diagnostic cue is determined to be credible, consumers use that cue when evaluating the product. When the diagnostic cue is determined to not be credible, consumers do not use that cue in evaluating the product. Study Two contributes to the literature in two ways. First, the study provides the first empirical examination of the effect of warranty on perceived quality when warranty is unexpectedly long. Second, this study adds to the literature by building credibility, using signals other than the firm's reputation.