This tendency toward overconfidence seems particularly strong in people who have the least cause to be overconfident. Justin Kruger and David Dunning explored this issue in detail in a 1999 paper in the Journal of and Social Psychology. Across a range of tasks from judging to logical reasoning, they found that the worst performers were the most overconfident in their abilities. The people who did best on these tasks were reasonably accurate at predicting how well they would do, but the people who did worst were highly overconfident.

This pattern is a potentially dangerous mix. It is potentially disastrous for someone to enter with into a situation in which they have no real ability.

The situation may not be quite as bad as it seems, though. A paper in the March, 2011 issue of the Journal of Experimental Psychology: Learning, , and by Tyler Miller and Lisa Geraci suggests that the worst performers may overestimate their performance, but they may not be truly overconfident.

As they point out, there are two dimensions of overconfidence. One way to be overconfident is to believe that you will perform better than you actually do perform. Technically, that is just overprediction. To be truly overconfident, you also need to be confident in your prediction for your performance. That is, you need to think you are going to do well in an upcoming situation, and you need to be relatively certain that your prediction is accurate.

Consistent with previous work, the people who performed well on the exam made reasonably accurate predictions for their grade. Those who performed poorly (getting grades below 70) tended to overpredict their score by 10 or more points.

However, the group that did most poorly on the exam was also the least confident in their predictions. That is, this group made bad predictions, but these individuals also had a sense that they did not have a good basis for making a prediction.

What is going on here?

The people who do most poorly in an area also tend to know the last about it. One reason why the worst performers overpredict performance is that they do not realize how much they don't know. Predictions by experts often get better, because they have a better sense of how much they know as well as of how much they don't know.

That said, at least some poor performers seem to have some clue that they are on shaky ground. That is why their confidence in their predictions is low.

Ultimately, though, you should recognize that you are likely to overpredict your performance. When you start out in a new area, be prepared to do less well than you anticipate that you will. Perhaps the knowledge that you tend to be overconfident will give you some to work harder to achieve the level of performance you hope for.

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