Haha have to cite a study here [Kruger and Dunning 1999, Unskilled and unaware of it ...] (recollection from CFA Level 3 material) So the authors of the study

Haha have to cite a study here [Kruger and Dunning 1999, Unskilled and unaware of it ...] (recollection from CFA Level 3 material) So the authors of the study asked people to rate how they have performed on a logical reasoning test. What they found is that people in the lower half of the test results scored less than 40% correct, yet they thought that their scored in the 60% range. This was particularly bad for the lowest 25% who got 10% correct. The irony is that people who did very well (top quartile) actually thought they performed worse (55% vs 85% performance) tl;dr: the skills needed to correctly answer questions are exactly the skills needed to evaluate performance. The best bet is to have some sort of objective measure. Learn a little bit about the field you are interested in evaluating others in. Think about fizz-buzz: a non-programmer can ask the question and get people to sweat