As a manager, you try to evaluate people fairly and objectively. But evaluation, by its very nature, calls for your perceptions and judgments about an employee’s performance. Your perceptions are biased by your own value system. In addition to keeping documentation, another way to reduce rater error is to be aware of some of the common biases that may affect your assessment.....

1. As a manager, you try to evaluate people fairly and objectively. But evaluation, by its
very nature, calls for your perceptions and judgments about an employee’s performance.
Your perceptions are biased by your own value system.
In addition to keeping documentation, another way to reduce rater error is to be aware of
some of the common biases that may affect your assessment.
Halo Effect
This is the tendency to give someone an overall high or low rating because the
employee rates high or low in one or two given areas.
Recent Behavior
If an employee recently did something very well or very poorly or had a particularly
dramatic event, this event can offset the general perception of how they have performed
over the past months.
Central Tendency
In an effort to avoid accentuating a difficult or negative evaluation for one employee, all
employees are rated in the middle.
Past Record
The employee should only be evaluated on the most recent performance period. Here,
previous ratings carry over and bias the current period evaluation.
Personality
There is a tendency to rate people who are considered likeable, popular or attractive
higher than they deserve. Conversely, people who are irritating, difficult or unpopular
may be rated lower than their results deserve.
Self Comparison
If the employee is in a job that the manager has ever occupied, there is a tendency to
rate that person lower because they do the job differently than the manager did.
Guilt by Association
If an employee is friendly with or supports a “poor performer,” there is a tendency to rate
that person lower. Another example is if there is a good performer on a poorly
performing team, that employee might be rated lower.
Greasy Wheel
This is a tendency to give a lower rating to the employee who is vocal or challenges the
manager, but gets the job done, than to the silent or cooperative poor performer.