Citadel Data Scientist Interview Questions
& Process
Real candidates share what happened, how many rounds they had,
and how the experience turned out.
Based on 7 interview experiences · FREE TO READ
Candidate interview experiences
First-hand accounts from people who interviewed at Citadel.
Citadel
Data Scientist
Entry Average Negative experience No offer 2 rounds
Interview process
Take home Technical screen
Interview formats
Technical Coding
It started with an online assessment that involved questions on pandas and SQL data manipulation. After passing that, the next stage was a live interview focused on statistics. The recruiter had mentioned that the second stage would be about coding, so I prepared for that, but I didn't expect many stats questions. I didn't move forward after that.
Confirmed questions2 questions
- Extract data details from a pandas DataFrame.
- Answer textbook statistics questions concerning random variables, including expectation and variance.
Citadel
Data Scientist
Mid Average Positive experience No offer 3 rounds
Interview process
Recruiter call Technical screen Onsite
Interview formats
Technical Case
It starts with a run-through of your resume and a look at how you've used data in the past and what outcomes it led to. Then, you'll tackle some case studies using different datasets to figure out investment-related insights.
Confirmed questions1 question
- Considering Dataset A, how would you go about creating features to forecast equity returns? What factors would you take into account?
Citadel
Data Scientist
Mid Average Neutral experience No offer 1 round
Interview process
Onsite
Interview formats
Technical Coding Behavioral
The onsite interview lasted around 6 hours. I talked to 3 people in the morning and 3 in the afternoon, with a 20-minute lunch break. They were friendly and some offered help when I was stuck. This role involves analyzing data, which is usually a trader's job. It's more focused on programming than building statistical models, which was unexpected. The technical problems were standard, like 'how many loops if you connect strings in a bowl,' and some C++ questions. However, there were also unusual questions like estimating Nigeria's population and its confidence interval. Despite the 'Data Scientist' title, there wasn't much testing on data science skills like machine learning. Be ready for advanced Python (2.x) and C++ questions.
Confirmed questions5 questions
- If I pick a number between 1 and 100 at random, how would you guess it? What if I told you the number is hard to guess, like close to 1 or 100?
- Estimate Nigeria's population and provide a 95% confidence interval.
- In a card game with a 52-card deck, after drawing 5 cards and returning 4, you keep 1. If the dealer knows your card, what strategy are they using?
Citadel Data Scientist Interview Questions
Quoted word for word from Citadel interview reports.
“Given the equation 16p + 1 = x^3, where p is a prime number, find the value of x.”
Read reports →“Given a square and three dots randomly placed on its four edges, what is the probability that these dots end up on different edges?”
Read reports →“In a card game with a 52-card deck, after drawing 5 cards and returning 4, you keep 1. If the dealer knows your card, what strategy are they using?”
Read reports →“If I pick a number between 1 and 100 at random, how would you guess it? What if I told you the number is hard to guess, like close to 1 or 100?”
Read reports →“Considering Dataset A, how would you go about creating features to forecast equity returns? What factors would you take into account?”
Read report →“Describe inorder tree traversal. Also, explain Python decorators and generators, C++ virtual destructors, map implementation, and tree insertion/search/delete complexities.”
Read report →“Can you tell me about the Data Science challenge on forecasting?”
Read report →“What's your attitude towards learning new things?”
Read report →“Tell me about your experience working with different datasets.”
Read report →Formats, difficulty and experience
Across all 7 Citadel interview reports.