June 4, 2018
1. Central Tendency Bias
This bias affects the most workers and prevents anyone from standing out. Managers giving reviews tend to rate towards the middle when giving so many reviews. It’s easy to say everyone is average once you’ve already written ten reviews. Managers can also rate employees in the middle of the scale if the employee out fear of a tough conversation with the employee. It’s much easier to kick the can down the road.
2. Similarity/Ingroup Bias
Do you have a favorite employee or manager? Someone who can do no wrong? Maybe they’re similar to you or simply someone you admire. One positive attribute can easily cloud judgement and result in an unfair review. Similarly, ingroup bias causes managers to unconsciously inflate friends’ ratings and undervalue employees who you may not be as close with. Managers like to pretend other employees don’t notice this trend. People notice.
3. Contrast Bias
Comparing employees to one another, instead of objectives or set goals, results in contrast bias. This is common for sales representatives or other jobs that require workers to reach quotas. Employees deserve individual reviews that reflect their contributions to the organization. Not every review has to be a stack racking exercise.
4. Recency Bias
Time can greatly affect the outcome of a performance review in a positive or negative way. The last few weeks or months may outweigh the rest of the period since it’s easier to recall. This is one of the reasons why feedback occurring more frequently is sweeping through like wildfire. It’s a tough ask to remember accomplishments or missed opportunities so far back. An employee may have had a win at the beginning of the period but a manager could have already forgotten and focus on something else. Be sure to keep the entire time frame in mind. Keeping notes of accomplishments and struggles throughout the period can help managers stay unbiased.
5. Halo/Horn Effect
Sometimes it’s just one thing, a strength of a weakness that managers focus on during a performance review. This cognitive bias doesn’t see the whole employee, but only one positive or negative attribute. Then, all scores for one employee are unfairly skewed to reflect the single poor or favorable quality. It’s pretty unlikely that anyone is great or terrible in all aspects of their job.