Common biases to look for when running a tech interview

Walking into an interview, you are almost always self-absorbed. You imagine the people on the other side of the table have all the power and somehow are looking at you to see if they can grant you some kind of favour.

This is never true, speaking from the other side of the table, its tough. You are not running this interview because you had nothing else to do with your time. Chances are you need someone to work on your project yesterday.

Furthermore, it’s fairly easy to gauge if the company will be a good fit for you, services like Glassdoor offer a window into the company culture. From a hiring perspective, most of the time a CV and linked in profile is all you have to go with.

In this situations, recruiters tend to substitute the hard problem of determining if a candidate is a fit with other easier to answer questions.

Of the many assumptions, in this entry, we shall be exploring the most common.

How well does the candidate do on aptitude tests?

Aptitude tests are by now an industry standard. They are the modern version of the IQ test.

To be fair, high IQ is a major predictor of success later on in life. Individuals with high scores tend to more easily grasp new concepts and apply them in practice. My argument then is not against IQ tests but against using them as the sole measure of capacity.

You see eventually it gets hard. Sure natural talent will help you breeze through the basics of the language and the framework, but no amount of it will make your first true mess up any easier.

In the office, we were discussing the intricacies of software development and whether it really is a high IQ sport as its touted. We concluded it wasn’t, 90% of the time, the work is processing simple inputs from the user and triggering the right events. As Thierry Schellenbach from Stream puts it

For many applications, the programming language is simply the glue between the app and the database

Then perhaps you should not be as worried about how high the IQ of the candidate is but how well they are able to understand and interpret your client’s needs.

Do I like this person?

Usually, this question is masked as “Are they a culture fit?”. Formally known as the Halo effect, we naturally drift to individuals we like.

Now, the good engineers I have met care a lot about their craft, not so much how symmetric their face is. By being ignorant of the fact you are actively biased towards likeable people, you may lose out on great talent.

This is where stereotyping happens. Take the unspoken case of ageism, it is far harder to be trusted as a developer once you hit the 40s. Somehow, coding has been taken as something only young people do. Thus when a middle-aged person walks into the interview room, your mind starts looking for signs something is terribly wrong with them.

For those who imagine they are somehow immune from this effect, think again, no one is. The bias is hardwired into your brain, you must then design your recruitment process to remove the bias.

How many twitter followers does the candidate have?

Sounds kind of stupid when read aloud doesn’t it? Yet this seems to be routine in a recruitment exercise. So much so almost all CVs I now see have a link to the candidate twitter profile.

I honestly have no idea why this happens, my best guess is a big followership implies others have also validated the talent and so you follow suit.

A friend of mine actively filters out candidates with an average of more than ten tweets per day. He reasons anyone who can afford to sink that much time into Twitter is not likely to be working on whatever they are actually paid to do. I don’t actively support this position but I think its worth some consideration.

What is their presence online?

Building a personal brand is very important, you should try to at least have content you control on the first page of the search results for your name.

This doesn’t mean you dismiss individuals who are not as adroit in the art of personal promotion. Maybe they just don’t like writing about themselves.

Open source software is great, but it’s not a requirement for you to contribute before you earn your stripes as a software engineer.

Have you ever experienced any of the issues mentioned above? Talk to me in the comment section below or on my twitter @jchex



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Software Project Manager