MockQuestions

Data Scientist Mock Interview

To help you prepare for your Data Scientist interview, here are 30 interview questions and answer examples.

Data Scientist was updated by on October 13th, 2021. Learn more here.

Question 1 of 30

Describe to me a data project you worked on in the past that you would do differently with the knowledge/experience you have acquired up to this point and/or new technology that was not available at the original time of the project.

This is a Behavioral question, which the interviewer will use to determine how you dealt with a specific issue in the past and how you would deal with it if you encountered it again while working for their organization. Behavioral questions are best answered by using the STAR format. STAR stands for Situation, Task, Action, and Results. Using this format will help you organize your answer and lead the interviewer through your story in a systematic manner.

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30 Data Scientist Interview Questions & Answers

Below is a list of our Data Scientist interview questions. Click on any interview question to view our answer advice and answer examples. You may view six answer examples before our paywall loads. Afterwards, you'll be asked to upgrade to view the rest of our answers.

  • Behavioral

    1. Describe to me a data project you worked on in the past that you would do differently with the knowledge/experience you have acquired up to this point and/or new technology that was not available at the original time of the project.

  • Behavioral

    2. Data Scientists do a lot of exploring and testing of hypotheses. Tell me about a time you were given freedom to explore a business problem with very few parameters. What was your initial approach in attacking this project?

  • Behavioral

    3. Describe a time when you had to present findings/recommendations to a non-technical audience. What strategies did you use to ensure the audience did not get confused and clearly understood the message?

  • Behavioral

    4. Describe a project where you had a surprisingly difficult time dealing with unstructured data. How did you overcome the obstacles and what tools did you use?

  • Behavioral

    5. Many companies rely on Data Scientists to tell them what analysis is possible with the data available. Talk about a time when you took the initiative to recommend a new business measure for the company to track.

  • General

    6. To be a successful Data Scientist, many in the industry believe it is important to stay up-to-date on the newest technologies and methodologies. What new data-related technology/methodology have you heard of that you wish you could learn more about?

  • General

    7. The work of a Data Scientist can have a large impact on the strategy, and ultimately success, of a business. Is there a time you felt your work as a Data Scientist had a profound impact on strategy development? Explain your role and contribution.

  • General

    8. When your job requires you to be immersed in data, you can discover some interesting patterns or trends. What is the most interesting discovery you made through the mining/exploration of data?

  • General

    9. In your past positions, have you had experience contributing to the improvement of data analysis processes, database management, data infrastructure, or anything along those lines? If so, please explain your contributions.

  • General

    10. How have past positions unrelated to data analysis helped you in your current profession as a Data Scientist?

  • Operational

    11. Can you describe some of the steps you take to ensure that a regression model fits the data?

  • Operational

    12. As a Data Scientist, how do you employ statistics to analyze data and develop business recommendations?

  • Operational

    13. Do you perform data wrangling and data cleaning before applying machine learning algorithms to your data analysis?

  • Operational

    14. Can you describe how Data Analysis is used by businesses and other organizations?

  • Operational

    15. In your opinion, is mean square error a good or bad measure of model performance?

  • Operational

    16. What are some of the assumptions required to accurately perform a linear regression analysis?

  • Operational

    17. Do you follow the hypothesis that many small decision trees are more accurate than one large one?

  • Operational

    18. How do you deal with an unbalanced binary classification when analyzing a data set?

  • Operational

    19. Data visualization is an important skill that will be used often when communicating results with stakeholders. Describe to me one of your most innovative data visualization ideas that went beyond pie and bar charts.

  • Operational

    20. Describe to me your experience with machine learning methods. Is there a particular method you have more experience with than others?

  • Technical

    21. Can you discuss some of the weaknesses of a linear analysis model?

  • Technical

    22. What are some of the differences between a histogram and a box plot?

  • Technical

    23. What statistical software programs do you have experience using in past positions in this field? Which one do have you the most experience with or feel the most confident using?

  • Technical

    24. Can you define cross-validation and describe how you use this process when analyzing a data set?

  • Technical

    25. What is a decision tree, and how do you use this in your job as a data scientist?

  • Technical

    26. What is Data Cleansing and why is it important in Data Analysis?

  • Technical

    27. Can you compare Sas, R, and Python programming tools and describe their use in Data Analytics?

  • Technical

    28. What experience do you have conducting text analytics? Describe a project you worked on that required text analytics.

  • Technical

    29. What data visualization tools do you have experience using? Which one is your favorite to use and why?

  • Technical

    30. What programming languages do you have experience using? Of these, which do you have the most experience with? Which do you have the least experience with?