Living in a Social World

Psy 324: Advanced Social Psychology

Miami University, Fall, 1996


Optimistic Bias in Perceiving Physical and Mental Health Risks

Ed Berger, Angela Magnuson, Missy Maxwell, & Jamie Tubbs

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 "People will come to believe what they want to believe only to the extent that reason permits" (Kunda, 1990).

      The optimistic bias is the tendency to view oneself as invulnerable (or less likely than others) to experiencing negative life events. This personal fable (Elkind, 1967) also involves the tendency to overestimate one’s probability of experiencing positive life events. For example, in the area of health, research has shown that more than half of surveyed individuals perceive that they are less likely than others to be afflicted with such health outcomes as drug addiction, cancer, tooth decay, and auto injury. Harris and Guten (1979) found that only a small proportion of the subjects in their study reported to be at a higher risk for a given disease while a much larger proportion assessed their risk as being lower.

     Diseases that are related to behavior risk factors,or diseases that show an increased perceived controllability, increase the optimistic bias in the perception of risk for that disease (Taylor, 1989; Weinstein, 1982, 1984, 1987). An illusory assessment such as this may actually lead some to engage in health-compromising behaviors including smoking, eating a high fat diet, unsafe sex, etc. Kunda (1990) suggested that engaging in the previously mentioned behaviors with the knowledge that it may lead to a controllable disease constitutes a threat to one’s intelligence. In order to preserve self-esteem, one is more motivated to assess his/her risk for the possible harmful outcomes of this behavior as being low. People are also not willing to conclude that their behavior may actually contribute to their probability of contracting a disease or being injured. Weinstein (1984, 1987) correlated self-reported health behaviors and perceived risk of related illness and found that the only high-risk behavior acknowledged as leading to increased risk of disease was smoking. And even though smokers are willing to acknowledge this increased risk, they might still have an optimistic bias pertaining to their individual risk for a smoking-related illness. In other words, they believe that their probablity is lower than the actual risk for disease.

      Another factor contributing to the optimistic bias is the nature of the comparison other. Studies have shown that when subjects are asked to compare their futures to the future of the "typical other person" (e.g. Perloff, 1987), " the average other" (Perloff, 1987), "(most) people they know" (e.g. Drake, 1984), or "other students at the same university and same sex" (e.g. Weinstein, 1980) the optimistic bias is prevalent. However, when comparing themselves with a good friend instead of "the average other," subjects do not display unrealistic optimism (Perloff & Fetzer, 1986). Perhaps the reason for this is that comparing oneself to good friends implies a comparison of individual to individual instead of a group as is the case with "the typical other person," for example. This can be explained by the "person positivity bias," which says that people value the individuals of a group more positively over the group as a whole (Sears, 1983). Hoorens and Bruunk (1993) tested both of these factors and found that subjects unrealistic optimism was high when compared to a random other or average other but diminished when comparing themselves to their best friends.

     We are interested in the differences or similarities of the optimistic bias in the areas of age, gender, and culture. Some of the questions we will be asking are: Is there a perceived difference between the risk-perception of adolescents and adults? Do adolescents display an increased illusion of invulnerability? Is there any cultural variation of the optimistic bias between the cultures of the East and West? Is there a difference in men’s and women’s risk perception of AIDS?

Learn More About:

Age Factors

Cultural Factors

Gender Factors

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 Drake, Roger A. (1984). Lateral asymmetry of personal optimism. Journal of Research in Personality, 18, 497-507.

 Harris, D. M., & Guten, S. (1979). Health protective behavior: an exploratory study. Journal of Health and Social Behavior, 20, 17-29.

 Hoorens, Vera, & Buunk, Bram P. (1993). Social comparison of health risks: locus of control, the person-positivity bias and unrealistic optimism. Journal of Applied Social Psychology, 23, 291-302.

 Kunda, Ziva. (1990). The case for motivated reasoning. Psychological Bulletin, 108, 480-498.

 Perloff, Linda S. (1987). Social comparison and illusions of invulnerability to negative life events. In C. R. Snyder, & C. Ford (Eds.), Coping with negative life events: clinical and social psychological perspectives on negative life events pp. 217-242). Plenum Press.

 Perloff, Linda S., & Fetzer, Barbara K. (1986). Self-other judgments and perceived vulnerability to victimization. Journal of Personality and Social Psychology, 50, 502-511.

 Taylor, Shelley E. (1989). Positive illusions: creative self-deception and the healthy mind. New York: Basic Books.

 Weinstein, Neil D. (1982). Unrealistic optimism about susceptibility to health problems. Journal of Behavioral Medicine, 5, 441-460.

 Weinstein, Neil D. (1984). Why it won't happen to me: perceptions of risk factors and illness susceptibility. Health Psychology, 3, 431-457.

 Weinstein, Neil D. (1987). Unrealistic optimism about susceptibility to health problems: conclusions from a community-wide sample. Journal of Behavioral Medicine, 10, 481-500.

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Social Psychology / Miami University (Ohio USA). Last revised: Wednesday, March 12, 2014 at 17:06:33. This document has been accessed 1times since April 20, 2002. Comments & Questions to R. Sherman