Contrast errors: the rater compares an individual, not against an objective standard, but against other employees.
Distributional errors: the rater tends to use only one part of a rating scale.
Leniency: the reviewer rates everyone near the top
Strictness: the rater favors lower rankings
Central tendency: the rater puts everyone near the middle of the scale
Rater bias: raters often let their opinion of one quality color their opinion of others.
Halo error: when the bias is in a favorable direction. This can mistakenly tell employees they don’t need to improve in any area.
Horns error: when the bias involves negative ratings. This can cause employees to feel frustrated and defensive.