Some managers favor candidates who went to the same school. There's also evidence that African-American sounding names, birthmarks, being pregnant, and being overweight puts candidates at a disadvantage.

To overcome this bias, identify the key skills and values in advance, then create a standard set of behavioral and situational questions to ask every candidate. Doing this can triple the manager's accuracy in predicting job performance.

Some questions are too easy to fake, for example, "What's your greatest weakness?" Other questions like brainteasers reveal more about the manager than the candidate.

Behavioral questions about a past experience can help anticipate future behavior. "Tell me about a time when.....