Data Scientist Statistics & Math Interview Questions
Practice 455 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."
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...
Generate Samples from Truncated Normal Distribution
Scenario You draw from a normal distribution but only keep observations that are greater than 1 (i.e., values below 1 are discarded). Assume the origi...
Test whether two distributions differ
You have two datasets collected from different systems or populations, and you want to determine whether they come from the same distribution. Explain...
Compute multi-step Markov probabilities and estimate transitions
Problem (Markov Chain Probabilities) You are working with a discrete-time Markov chain over a finite set of states $S = \{s_1, \dots, s_n\}$. The chai...
Derive a CDF from a PDF
During a first-round Data Scientist interview, you are asked a coding-and-statistics question: You are given a valid probability density function f(x)...
Calculate Expected Draws for X > 0.8 in Uniform(0,1)
Scenario Quick probability check during a first-round screen to gauge statistical intuition. Question Let X ~ Uniform(0, 1). You draw independent samp...
How to Update Bayesian Model for Concept Drift?
Beta–Binomial CTR Model: Prior, Likelihood, Posterior, Smoothing, Intervals, and Drift Context You are discussing statistical foundations for a Bayesi...
Calculate Expected Comments and Confidence Interval Analysis
Scenario You are analyzing the distribution of comment counts per post for a social platform feature over a fixed time window. Let X be the random var...
Calculate Expected Flips for Heads-Tails Sequence
Probability Check — Waiting Time for HT Setup - You repeatedly flip a fair coin (independent flips; P(H)=P(T)=1/2). - Stop as soon as the consecutive ...
Answer Statistics Questions for Spokeo DS Role Quiz
Timed Statistics Quiz: Short-Answer Concepts Answer the following independent questions succinctly. Assume standard statistical definitions and that s...
Choose Randomization Unit and Mitigate Network Effects
A/B Test Design for a New Messenger Feature with Network Effects Context You are designing an A/B test for a new Messenger feature in a social messagi...
Analyze Video View Distribution: Mode, Median, Mean Comparison
Scenario You are analyzing user engagement on a short-video sharing product. The team needs statistical insights into how views and shares behave acro...
Assess Probability of Heads in Coin Tosses
Probability with Coin Tosses and the Normal Distribution Context Onsite data scientist screening question assessing basic probability and distribution...
Compute probability in urn with green returns
Urn Sampling with Replacement for Greens Only You have an urn with colored balls. You repeatedly draw one ball uniformly at random: - If the ball is g...
Explain Type I vs Type II errors
Prompt In hypothesis testing: 1. Define Type I error and Type II error. 2. Explain how they relate to significance level \(\alpha\) and power \(1-\bet...
Compare Ad-Insertion Strategies: Expected Ads and Probabilities
Newsfeed Ad-Insertion Strategies You are evaluating two ways to insert ads into a user's newsfeed. Assume a user views a contiguous sequence of posts....
Calculate Probability of Third Card Being an Ace
Probability Puzzle: Drawing Aces Setup - You draw 3 cards without replacement from a standard 52-card deck (4 Aces, 48 non-Aces). - It is known that a...
Determine Superiority of Model A Using Hypothesis Testing
Scenario A search feature marks a user session as a success only if both the relevancy and accuracy binary flags equal 1. Two ranking models were A/B ...
Measure Causal Impact of Self-Selected App Redesign
Measuring Causal Impact of an Opt-in Mobile App Redesign Context A mobile app ships a redesigned UI as a new version. Users can choose to upgrade (opt...
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...