10 interview questions every data scientist should know

If you just got the interview invite for your dream data science job, you probably did two things: 1. celebrated, and 2. went into stress mode.

Fortunately, you are not the first person ever to go through the data science interview process, so you can learn from your predecessors. While any interviewer might throw you a curveball, there are ways to prepare.

First up, 10 questions you should expect during the interview. Then we’ll share some must-know tips to ensure you’re walking out with a job offer (or at least a ton of experience for next time).

10 questions to expect during the interview

Time to do your homework. Use this list of potential data science interview questions to prepare. This doesn’t capture every possible scenario, but if you can answer all of these clearly, you’ll be in good shape to respond to anything your potential employer throws your way.

1. Describe one big project you’ve worked on in the last year.
2. Name one data scientist you admire.
3. What do you love most about your job?
4. How would you describe data science to someone outside the field?
5. Describe your favorite method for data cleansing.
6. Explain cross-validation.
7. What is the difference between supervised and unsupervised learning?
8. Define selection bias.
9. How would you define covariance and correlation?
10. Describe overfitting and underfitting, and offer one possible solution.

Preparing for your interview

Here are a few more tips so you can prep now and when the time comes, you can focus your energy on remembering everyone’s names.

• Brush up on the basics. The role you’re applying for is no doubt highly specialized and industry-specific. But they don’t expect you to know everything about that exact job. Just be prepared to talk clearly about the Data Science 101 stuff you already know.
• Be aware of current industry trends. The field of data science is still in its relatively early stages and changing quickly, so it wouldn’t hurt to show your future employer that you’re keeping up. Read some recent news in the world of data science, and get prepared to name drop your favorite data science blog or industry news site.
• Prepare for the normal questions, too. Even though it’s a highly technical field, your future supervisor is still human. They’ll want to get a feel for who you are and how you’ll work together. Relax and engage in the small talk, even if your last vacation has nothing to do with your data visualization expertise.

Types of interview questions

Your interview questions will fall into the following categories:

• Questions about your work experience.
• General knowledge of the field.
• Getting to know your work style.

All of this information is important if they’re considering you for a full-time data science position. When your interviewer asks a question, even if it seems obvious or irrelevant, try to figure out which category it falls into and what they’re trying to learn about you.

Anything we missed? Share the toughest question from your last data science interview by tweeting @thinkful.

And when you feel ready to nail the interview, make sure you’ve also done these four things to launch a career in data science.

Artwork by Rachel Knobloch.