Data Scientist Statistics & Math Interview Questions
Practice 454 real Statistics & Math interview questions for Data Scientist roles. From companies including Meta, Capital One, Google, Amazon, Uber.
"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"
"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"
"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."
"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."
"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."
"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."
"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Perform and justify t-tests
A/B Test: Compare Mean Watch Time Between Variants A and B Context: You ran an A/B test measuring per-user daily watch_time (in seconds). You obtained...
Test classifier difference with McNemar's test
Paired Comparison of Two Classifiers via McNemar's Test You evaluated two classifiers on the same 10,000 labeled examples and summarized the paired ou...
Explain and interpret p-values correctly
Context You are evaluating a change to a fraud decision rule (e.g., a new threshold or step-up authentication rule). You run an experiment comparing C...
Estimate constant under absolute loss
Suppose you have observed target values \(y_1, y_2, \dots, y_n\), and you want to fit the simplest possible model that predicts the same constant valu...
Compute decay, OLS, and classic probability results
You are asked several probability/statistics questions. 1) Radioactive decay (half-life) A radioactive atom has a half-life of 1 day. Assume each atom...
Write the logistic regression loss function
Logistic Regression Loss Consider binary logistic regression. - Dataset: \(\{(\mathbf{x}_i, y_i)\}_{i=1}^n\) - Labels: \(y_i \in \{0,1\}\) - Model: \(...
Solve quantitative word and algebra problems
Quantitative Mini-Problems (Independent) Solve each problem independently. Show your setup clearly. Use standard unit conversions and give exact value...
Determine Appropriate Statistical Test for Comparing Means
A/B Test: Active Minutes After Two Weeks Scenario You ran a two-week A/B experiment on a new algorithm. The primary metric is user active minutes. Ass...
Explain Bayes’ Theorem and P-Value in Decision-Making
Statistics Fundamentals: Bayes' Theorem and p-Values Context Stakeholders want clear, decision-focused explanations of two foundational concepts used ...
Estimate Treatment Effects Using PSM, DiD, and DML Methods
Causal Impact of Marketing Campaigns: PSM, DiD, Synthetic Control, and DML Scenario You have observational data from a marketing campaign where some u...
Determine Impact of New Chat-Notification on User Engagement
Scenario A product team wants to determine whether a new chat-notification design increases daily active users (DAU) in Google Workspace Chat. Task De...
Detect and address multicollinearity
Prompt You fit a linear/logistic regression model and suspect multicollinearity among features. 1. What is multicollinearity and why is it a problem? ...
Sketch distributions and compare mean/median/mode
Distribution sketches and summary-stat comparisons Answer the following conceptual statistics questions. Assume you have a large random sample and you...
Explain multicollinearity and OLS assumptions
Linear Regression Technical Screen: OLS Assumptions and Multicollinearity Context: You are asked to summarize core OLS assumptions, explain multicolli...
Compute expected arc length on a circle
On the unit circle (radius \(1\), centered at the origin), pick three points independently and uniformly at random on the circumference. These three p...
Compare Normal and Poisson Distributions in Statistics
Modeling Counts vs. Continuous Measurements Scenario You are modeling event counts (e.g., number of clicks) versus continuous measurements (e.g., resp...
Explain P-value, Confidence Interval, and Multiple Testing Adjustments
A/B Testing and Inferential Statistics for a New Product Launch You are running online A/B experiments to evaluate a new product launch. Assume standa...
Solve animals-and-legs count
Barn Legs Puzzle (Linear Equations) Convert the word problem into a small system of linear equations and solve. You have a barn with three types of an...
Estimate bots and CI from DAU spike
Mixture Spike and Mean-Difference Inference for Daily Comments Context A product has DAU (daily active users) = 2,000,000. On day T, total comments in...
Match Netflix profit; derive required subscribers
Subscription Profit and Break-even (All Monthly) Assume all figures are monthly and "M" denotes millions. We model subscription profit as: - Profit = ...