Today I want to talk about the dreaded term Rater Bias (cue scary ghost sounds).

So what is “Rater Bias”?  And what’s this “real world” you speak of?

Rater Bias is a reflection of what it means to be human.  Some managers tend to rate employees in a lenient manner, others in a more strict manner.

Remember the idiom “first impressions are the most lasting”?  Sometimes, even that turns out to be true as a manager rates an employee.

If you have humans working at your organization, then Rater Bias is happening in your organization right now.

So that leaves two questions:

  • How can I identify when Rater Bias is happening?
  • How can I mitigate Rater Bias in the future?

Let’s begin….

How can I identify Rater Bias?

Let’s talk about the types of rater bias we can identify: strict and lenient raters.  Other types of rater bias are nearly impossible to detect, and even when we think we see rater bias, we have to double check because there are exceptions to every rule.

Before we get too deep, we’re going to use statistics to identify bias.  But it’s important to note that even statistics can be misleading.   Read this article to learn more:  How to Hang Yourself with Statistics

Let’s take a look at some actual customer data.




Editor’s Note: This post was originally published on Trakstar.com. In April 2023, Mitratech acquired Trakstar, a leading provider of performance management, talent acquisition, and workforce analytics solutions. The content has since been updated to reflect Mitratech’s broader commitment to supporting the entire employee lifecycle — from recruitment and onboarding to learning and development — as well as the integration of HR compliance best practices across our growing Human Resources portfolio.