Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Marketing (Business Administration)

First Advisor

Abhijit Biswas


Comparative advertising has become a popular and powerful promotion tactic for companies competing in a highly competitive marketplace. While most research examined comparison advertisements, focusing on one brand being compared to a competitor brand, "within-brand comparison" advertising has been neglected. Within-brand comparison advertising compares the attributes of an extension brand with the attributes of an original or replaced brand. This dissertation examines the relative effectiveness of two forms of comparative advertising tactics, "within-brand comparison" versus "across-brand comparison". The moderating effects of "brand image" and "attribute relevance" and the mediating effect of "ad believability" are also assessed by an experiment. Based on the Persuasion Knowledge Model and the Characterization-Correction Model, the results revealed that across-brand comparison ads resulted in lower ad believability, attitude toward the ad, attitude toward the brand, purchase intention, and more counterargurnents and tactics-related cognitions than within-brand comparison ads under low brand image and attribute irrelevance conditions. Interaction effects were assessed under the conditions of high brand image and attribute relevance. The findings implied that high-image brands enjoy the flexibility of using both types of comparative ads as long as they are employing relevant attributes. On the other hand, low-image brands are more likely to benefit from only within-brand comparison ads employing relevant attributes. It was also found that the within-brand comparison ads resulted in more favorable consumer responses than the across-brand comparison ads irrespective of attribute relevance. However, the results also suggest that low-image brands should prefer within-brand comparison ads to across-brand comparison ads and avoid using irrelevant attributes. Overall, within-brand comparison ads seem to result in more favorable outcomes than across-brand comparison ads while avoiding the potential risks of legal problems, competitor retaliations, and brand confusion.