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Author ORCID Identifier


Open Access Dissertation

Document Type


Degree Name

Doctor of Philosophy (PhD)

Degree Program


Year Degree Awarded


Month Degree Awarded


First Advisor

Andrew Cohen

Second Advisor

Jeff Starns

Third Advisor

Adrian Staub

Fourth Advisor

Linda Isbell

Subject Categories

Cognitive Psychology


Context effects such as the attraction, compromise, and similarity effects demonstrate that a comparison process, i.e., a method of comparing dimension values, plays an important role in choice behavior. Recent research suggests that this same comparison process, made more flexible by allowing for a variety of comparisons, may provide an elegant account of observed correlations between context effects by differentially highlighting dimension-level and alternative-level stimulus characteristics. Thus, the present experiments test the comparison process as a critical mechanism underlying context-dependent choice behavior. Experiment 1 provides evidence that increasing a dimension-level property, spread, promotes the attraction and compromise effects and reduces the similarity effect, whereas increasing an alternative-level property, dispersion, introduces an alternative-level bias that influences choice in concert with the decoy. Experiment 2 utilizes eyetracking to test the influence of stimulus presentation format on information acquisition patterns and context-dependent choice behavior. Contrary to predictions, a By-Alternative presentation format appears to increase within-dimension transitions in eye fixations relative to a By-Dimension presentation format. Lastly, four computational models with theoretical accounts of the development of context effects over time were fit to joint choice and response time data. Though the MLBA provided the best fits to the subject-level mean choice proportions, it could not capture the crossover in preference between the target and competitor across RT quantiles; rather, MDFT and the AAM performed best in this regard. The present work therefore not only provides new insights into the relationship between choice and response times in preferential choice but sets important new constraints for theoretical models that seek to account for such behavior.