Not knowing what we don't know leads to bad decision making, says Cornell study

http://www.news.cornell.edu/stories/Oct05/self.insight.ssl.html

Oct. 7, 2005

By Susan Lang
SSL4@cornell.edu

ITHACA, N.Y. -- Dozens of studies agree: Most people overrate their own abilities. This tendency can have severe consequences: young adults making poor decisions about college and careers, pilots flying into storms and overconfident doctors making erroneous diagnoses.

According to a Cornell University expert on self-insight who has published two studies on the topic as well as a new book, "Over a lifetime, people base thousands of decisions on impressions of their skill, knowledge, expertise, talent, personality and moral character." However, says David Dunning, professor of social psychology at Cornell, "People's capacity to evaluate themselves and predict their behavior is usually quite modest and often much more meager than common intuition would lead one to believe."

Dunning has conducted dozens of studies showing that people often hold overinflated views of their expertise and character. His latest study in the most recent issue of Psychological Science in the Public Interest (Vol. 5:3) shows that this psychological phenomenon can have far-reaching implications in health, education and the workplace. His co-authors are Chip Heath of Stanford University and Jerry Suls of the University of Iowa.