Interview Questions for Data Scientists

Great data scientists come from such diverse backgrounds that it can be difficult to get a sense of whether someone is up to the job in just a short interview. In addition to the technical questions, I find it useful to have a few questions that draw out the more creative and less discrete elements of a candidate’s personality. Here are a few of my favorite questions.

  1. What was the last thing that you made for fun?

    This is my favorite question by far — I want to work with the kind of people who don’t turn their brains off when they go home. It’s also a great way to learn what gets people excited.

  2. What’s your favorite algorithm? Can you explain it to me?

    I don’t know any data scientists who haven’t fallen in love with an algorithm, and I want to see both that enthusiasm and that the candidate can explain it to a knowledgable audience.

    Update: As Drew pointed out on Twitter, do be aware of hammer syndrome: when someone falls so in love with one algorithm that they try to apply it to everything, even when better choices are available.

  3. Tell me about a data project you’ve done that was successful. How did you add unique value?

    This is a chance for the candidate to walk us through a success and show off a bit. It’s also a great gateway into talking about their process and preferred tools and experience.

  4. Tell me about something that failed. What would you change if you had to do it over again?

    This is a tricky question, and sometimes it takes people a few tries to get to a complete answer. It’s worth asking, though, to see that people have the confidence to talk about something that went awry, and the wisdom to have recognized when something they did was not optimal.

  5. You clearly know a bit about our data and our work. When you look around, what’s the first thing that comes to mind as “why haven’t you done X”?!

    Technical competence is useless without the creativity to know where to focus it. I love when people come in with questions and ideas.

  6. What’s the best interview question anyone has ever asked you?

    I’d like to wish for more wishes, please.

I’m always looking for new and interesting things to add to my list, and I’d love to hear your suggestions.