Unconscious Bias

This post came across my Twitter feed this week that talks about some of the spurious, meaningless reasons software engineering candidates are rejected. It’s challenging to evaluate candidates and we have a lot of productive discussions about how best to do that, but there some personal characteristics that we know are irrelevant to job performance: gender, race, age, sexual orientation, marital status, parental status, accent, where you grew up, etc. But even though we know those characteristics are irrelevant, they can still unconsciously affect how we evaluate and work with people through something called unconscious bias.

Unconscious bias manifests in some scary and surprising ways. For example, elementary school teachers give girls lower scores on math tests, unless they don’t know the gender of the students.

Another study examined gender bias in academic science. From the abstract: “In a randomized double-blind study (n = 127), science faculty from research- intensive universities rated the application materials of a student—who was randomly assigned either a male or female name—for a laboratory manager position. Faculty participants rated the male applicant as significantly more competent and hireable than the (identical) female applicant. These participants also selected a higher starting salary and offered more career mentoring to the male applicant. The gender of the faculty participants did not affect responses, such that female and male faculty were equally likely to exhibit bias against the female student.”

Bias can even have far reaching, unintended affects. Early marketing of personal computers targeted almost exclusively boys and that probably had an affect on the number of women seeking computer science degrees today.

One of the ways to combat unconscious bias is to learn more about it, which you can do with these resources:

If you’re evaluating a job candidate take a minute to think about how biases might be affecting your judgement. In fact, this can be a valuable thing to do in any interactions you have.

Note: This is based on a series of posts I’ve been putting together at work to educate coworkers on diversity and inclusion topics.


Microaggressions are small, often unintentional actions that can make others feel out of place. Examples can include asking where someone is from, acting surprised when someone doesn’t know something, or always expecting women to do office-keeping work. They can make people feel like they don’t belong and distract them from doing their actual jobs. “Micro”-aggressions might not sound so bad, but over time and many interactions they create an unwelcoming environment that can cause employees to leave or cause people to not want to attend events. As an example, a friend of mine almost swore off of all tech events after she went to a social event where everyone ignored her and talked to her lawyer husband instead.

It’s everyone’s job to make sure they’re actively creating a environment in which everyone feels that they fully belong. You can help by learning more about microaggressions and doing your best to avoid committing them (they hurt even when you don’t mean them to).

Here are a couple of good links that describe what migroaggressions are and the affect they have:

This post does a great job explaining how microagressions affect your life:

The Recurse Center’s social rules are very useful for helping you avoid committing microaggressions:

Note: This is based on a series of posts I’ve been putting together at work to educate coworkers on diversity and inclusion topics.