Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Award

Summer 2015

Document Type


Degree Name

Master of Arts (MA)


Department of Graduate Psychology


Richard Fuller West

Jeff Dyche


This study examined the extent to which myside bias was observed in the context of ethical decision making. In judgment and decision making research the resistance of myside bias is described as a component of rational thinking. Thus, to some effect, this study aimed to examine the extent to which people act rationally when making ethical decisions. Measures of thinking dispositions (actively open-minded thinking and need for cognition) as well as measures of cognitive reflection and probabilistic knowledge were included in the study to examine their associations with myside bias in ethical decisions. Modest myside bias effects were observed between and within-subjects, however, for within-subjects bias the effect failed to reach statistical significance. Exploration of the data beyond the study’s main research questions revealed significant myside bias effects for participants categorized as utilitarian. Finally, actively open-minded thinking was found to moderate myside bias effects.