Self-test of Overconfidence
For each of the following ten items, provide a low and high guess such that you are 90 percent sure the correct answer falls between the two.
Your challenge is to be neither too narrow (ie, overconfident) not too wide (ie, underconfident).
If you successfully meet this challenge, your result should at be least 8 correct (94% likelihood).
You can be 99.9% sure of getting at least 6 correct ...
Source: Confident Decision Making, J. E. Russo & P. J. H. Schowmaker, 1989, Piatkus, London p 71