Should Confidence Be Trusted?

See allHide authors and affiliations

Science  17 Sep 2010:
Vol. 329, Issue 5998, pp. 1478-1479
DOI: 10.1126/science.1195983

You are currently viewing the summary.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution


Imagine two witnesses in a courtroom. One is absolutely sure of her testimony; the other gives opposing testimony, but is less confident. Who would you trust more? All else being equal, we would tend to trust the former, because we believe that judgments made with high confidence are more accurate. This correlation between confidence and accuracy, though often true, unfortunately is not infallible. On page 1541 in this issue, Fleming et al. (1) report a relationship between the brain scans of people obtained by magnetic resonance imaging (MRI) and how seriously we should take their expressed level of confidence.