Bain & Company Data Scientist Interview Questions + Guide in 2024

Bain & Company is a global management consulting firm known for partnering with the world’s most ambitious change-makers to redefine industries and achieve extraordinary results. With a presence in over 65 cities across 40 countries, Bain prides itself on delivering unparalleled client advocacy since its founding in 1973.

At Bain & Co, data scientists play a pivotal role in driving data science projects that empower case teams and clients to extract, transform, and interpret their data, often leveraging machine learning techniques. They focus on effective communication and training, ensuring that both Bainies and clients understand the rationale and value behind the analytical methods proposed, thereby delivering lasting impact.

This guide will provide insights into the interview process, commonly asked Bain & Company data scientist interview questions, and valuable tips to help you succeed. Let’s get started!

The interview process usually depends on the role and seniority. However, you can expect the following on a Bain & Company data scientist interview:

Recruiter/Hiring Manager Call Screening

If your CV is shortlisted, a recruiter from Bain will contact you to verify critical details about your experiences, skill level, and reasons for applying. Behavioral questions may also be a part of the screening process.

Sometimes, the hiring manager might join the call to answer your queries about the role and the company. They may indulge in surface-level technical and behavioral discussions to gauge your fit.

The recruiter call typically lasts around 30 minutes.

Technical Virtual Interview

Successfully navigating the recruiter round will result in an invitation for a technical screening round. This usually involves a video conference with screen sharing. Questions during this stage might include data analysis, ETL pipelines, and coding problems.

Technical assessments may incorporate statistical problem-solving, data analysis, and model interpretation in the context of a data scientist role. Your proficiency with hypothesis testing, probability distributions, and machine learning fundamentals may also be evaluated.

Real-world scenarios, such as case studies or business problems, might also be assigned depending on the position’s seniority.

Onsite Interview Rounds

You can attend onsite interview rounds if you do well in the technical round. This phase generally includes multiple interviews with team members and senior management at the Bain office.

Your technical prowess will be assessed, including programming and ML modeling capabilities. Additionally, there might be a presentation round where you’ll explain your approach to any take-home assignments you were given.

Behavioral and Cultural Fit Interviews

Apart from technical interviews, Bain places a significant emphasis on cultural fit. Expect numerous behavioral questions to understand how you handle stress, work within teams, and solve problems in real-world business environments.

Questions could include:

• Can you tell us about yourself?
• What attracted you to Bain & Company and this role?
• Describe a challenging data analysis project you worked on. How did you approach it, and what were the results?
• How do you handle multiple projects with tight deadlines?

Typically, interviews at Bain & Company vary by role and team, but commonly Data Scientist interviews follow a fairly standardized process across these question topics.

1. How would you set up an A/B test for button color and position changes?

A team wants to A/B test multiple changes in a sign-up funnel, such as changing a button from red to blue and/or moving it from the top to the bottom of the page. How would you set up this test?

2. How would you forecast Facebook’s revenue for the next year?

An executive asks you to forecast Facebook’s revenue for the coming year. How would you approach this task?

3. How would you determine if an email campaign redesign led to increased conversion rates?

An E-commerce store’s new-user-to-customer conversion rate increased from 40% to 43% after launching a new email journey. However, the rate was 45% a few months prior. How would you investigate if the redesign caused the increase?

4. How would you ensure data quality across different ETL platforms for PayPal’s market research?

PayPal’s Southern African division uses multiple ETL pipelines to connect data marts with a survey platform’s data warehouses, including translation modules for text data. How would you ensure data quality across these platforms?

5. How would you conduct an experiment to test Uber’s ETA range feature?

A PM at Uber wants to test a new feature displaying ETA as a range (e.g., 3-7 minutes) instead of a direct estimate. How would you conduct this experiment and determine if the results are significant?

6. Why would the same machine learning algorithm generate different success rates using the same dataset?

Consider why a machine learning algorithm might produce varying success rates even when applied to the same dataset. What factors could contribute to these differences?

7. Write a function min_distance to find the minimum absolute distance between elements in an array and return all pairs with that distance.

Given an array of integers, write a function min_distance to calculate the minimum absolute distance between two elements and return all pairs having that absolute difference. Ensure the pairs are in ascending order.

8. Write a query to select the top five most expensive projects by budget-to-employee count ratio, accounting for duplicate rows.

Given two tables, projects and employee_projects, write a query to select the five most expensive projects by budget to employee count ratio. Ensure to account for duplicate rows in the employee_projects table.

9. Write a function to simulate drawing balls from a jar.

Given a list jar with ball colors and a list n_balls with corresponding counts, write a function to simulate drawing a ball from the jar.

10. Design three classes: text_editor, moving_text_editor, and smart_text_editor with specific functionalities.

Create three classes: text_editor, moving_text_editor, and smart_text_editor. Each class should have specific methods for writing, deleting, and performing special operations on text.

11. Write a query to determine the top 5 actions performed during Thanksgiving week and rank them.

Given an events table, write a query to determine the top 5 actions performed during the week of Thanksgiving (11/22/2020 - 11/28/2020) and rank them based on the number of times performed. Include the action and their rank in ascending order.

12. How would you explain what a p-value is to someone who is not technical?

Explain the concept of a p-value in simple terms to a non-technical person, focusing on its role in determining the significance of results in hypothesis testing.

13. What is the probability that it’s actually raining in Seattle, given your friends’ responses?

You called 3 friends in Seattle to ask if it’s raining. Each has a ²⁄₃ chance of telling the truth and a ¹⁄₃ chance of lying. All 3 said “Yes.” Calculate the probability that it is actually raining.

14. What is the probability of drawing three cards in increasing order from a shuffled deck of 500 cards?

Imagine a deck of 500 cards numbered from 1 to 500. If you pick three cards one at a time, what is the probability that each subsequent card will be larger than the previous one?

15. How would you test if survey responses were filled at random by certain individuals?

You have survey data from multiple-choice questions. Describe how you would test if some individuals filled out the survey randomly rather than truthfully.

16. What is the probability of a biased coin landing heads exactly 5 times out of 6 tosses?

Given a biased coin that lands heads 30% of the time, calculate the probability of it landing heads exactly 5 times out of 6 tosses.

You should plan to brush up on any technical skills and try as many practice interview questions and mock interviews as possible. A few tips for acing your Bain & Company data scientist interview include:

• Technical Expertise: Brush up on your coding skills, particularly in Python, R, and SQL. Make sure you’re comfortable solving statistical problems and applying machine learning techniques.
• Case Studies: Be prepared for case studies involving real-world business problems. Practice structuring your solutions and explaining them clearly.
• Behavioral Fit: Bain puts significant emphasis on cultural fit, so ensure your answers reflect teamwork, problem-solving abilities, and alignment with Bain’s values.

What is the average salary for a Data Scientist at Bain & Company?

According to Glassdoor, Data Scientists at Bain & Company earn between $162K to $206K per year, with an average of $181K per year.

What skills and experience are required for the Data Scientist role at Bain & Company?

Candidates are expected to have strong expertise in implementation of data science techniques, along with a good understanding of mathematical and statistical models. Excellent coding skills in Python and/or R, SQL, and familiarity with cloud platforms like AWS or Azure are also important. Additionally, candidates should possess strong communication skills and the ability to translate analytical insights into business impacts.

What can I expect from Bain & Company’s work environment and culture?

Bain & Company prides itself on being a top place to work, emphasizing diversity, inclusion, and collaboration. The company supports continuous learning and professional growth, providing a vibrant, supportive environment where employees can thrive. Teams are enthusiastic and helpful, ensuring you have the resources needed for successful client delivery.

Navigating the interview process for a Data Scientist position at Bain & Company can be a challenging yet rewarding experience. With a thorough and structured approach, you can expect various stages, including initial phone screens, technical assessments, and multiple interview rounds focusing on both technical skills and cultural fit. While the process may be lengthy and demanding, Bain’s supportive and passionate team members make it worthwhile.

If you’re looking to prepare thoroughly and increase your chances of success, make sure to visit our in-depth Bain & Company Interview Guide.

Good luck with your interview!