Date of Last Revision

2023-05-03 13:03:02



Degree Name

Bachelor of Arts

Date of Expected Graduation

Spring 2019


In today’s political climate, when basic facts and reasoning are seemingly up for debate, it is increasingly important to be able to identify well-reasoned arguments, regardless of one’s political leanings, and to retain this skill throughout the lifespan. Research has shown, however, a persistent belief bias—a tendency to judge an argument’s validity based on its conclusion’s agreement with one’s beliefs, rather than its logical quality. Other findings suggest that belief bias can be reduced by instruction to avoid belief bias. The current project seeks to explore whether older adults, believed to be more prone to biased reasoning, respond differently to such instruction, as well as to identify other potential individual differences in belief bias. Participants (41 young adults, 33 older adults) completed an online survey in which they were asked to evaluate valid and invalid syllogisms about political topics, both before and after instruction to avoid belief bias. Contrary to the literature, there was no significant difference between the bias scale scores or correction post-manipulation based on age group; however, response to de-biasing instructions was inversely related to political conservatism. Findings call into doubt the general statement that older adults are categorically more biased, and further research is suggested.

Research Sponsor

Jennifer Tehan Stanley

First Reader

Andrea Snell

Second Reader

Luis Proenza



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