The effect of irrelevant preference arguments on consumer choice

Consumers are often exposed to the arguments used by other consumers for supporting or rejecting particular alternatives, through word-of-mouth, testimonial ads, or other means. We propose that a reason for preferring a particular alternative that is irrelevant to the consumer receiving the communication tends to decrease the alternative's choice probability. Similarly, an irrelevant reason used to reject an alternative can enhance its choice probability. These propositions were supported in two studies in which respondents were told that, due to budget constraints, each questionnaire was designed for use by two respondents. In all cases, we systematically manipulated the choices and reasons provided by “Respondent I,” and the (real) subjects became the second respondent. As predicted, subjects were less likely to choose the alternatives selected by “Respondent 1” if the choices were supported by idiosyncratic (and irrelevant to most subjects) reasons (e.g., “I chose Breyer's ice cream because it is kosher”) and more likely to choose alternatives that were rejected for irrelevant reasons (e.g., “Quality Inn does not have a sauna”). Alternative explanations for the effects of irrelevant preference arguments are explored. We discuss the theoretical and practical implications of the findings.