Assigning Performance Ratings

There are a number of common rater errors that can occur during the performance review process: 

Tendency Bias:

  • Occurs when a rater rates performance of all people at a certain level, regardless of what their actual performance is. Some raters are very strict or conservative in their ratings and give lower review scores. Others raters either rate people very high or play safe by giving average ratings.

Recency Bias:

  • Occurs when a rater fails to look at performance for the entire review period and lets recent events overshadow all performance.

Personal Bias:

  • Occurs when personal beliefs, assumptions, preferences, or lack of understanding about the person being rated leads to unfair evaluation.

Competitive Bias:

  • Occurs when a rater rationalizes that no one under his/her supervision should be given performance rating higher than they themselves might receive.

Halo Effect:

  • Occurs when a rater attaches positive significance to a single performance factor and gives similar ratings on other performance elements.

Horns Effect:

  • Is the opposite of the halo effect. It occurs when a rater attaches negative significance to a single performance factor and gives similar, low ratings on other performance elements.

Contrast Effect:

  • Occurs when raters rate people one after another. The rating of an exceptional performer or a very poor performer could affect the subsequent ratings of other individuals.

Assess Your Rating Performance

Rater Performance Checklist (pdf)