Data Scientist Machine Learning Interview Questions
Practice 434 real Machine Learning interview questions for Data Scientist roles. From companies including Meta, Amazon, Google, Capital One, TikTok.
"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."
Design a lead-scoring model
Question You are interviewing for a Data Scientist role on a marketing/growth team. Sales has limited outreach capacity, so the business wants a lead-...
Dice Duel: 30-Sided Die vs. 20-Sided Die with One Blind Reroll
Alice and Bob play a dice game. Alice has a fair 30-sided die (faces $1$ through $30$) and Bob has a fair 20-sided die (faces $1$ through $20$). Each ...
Design an ad recommendation and ranking system
You are building an ad recommendation/ranking system for a content feed (e.g., short-form videos). At each feed position, you may show either an organ...
Explain ROC-AUC vs PR-AUC tradeoffs
Question You trained a binary classifier that outputs predicted probabilities. Compare ROC-AUC and PR-AUC (the latter usually reported as Average Prec...
Explain and tune decision trees robustly
Decision Trees: Splitting, Tuning, Overfitting, and When to Use Ensembles Context: You built a CART-style decision tree for a take‑home ML project. An...
What are linear regression assumptions?
You fit an ordinary least squares (OLS) linear regression model. 1) What are the key assumptions behind OLS (for unbiasedness and for valid inference)...
Design Siri-vs-GPT query routing
You are a Data Scientist at Apple designing a feature that decides whether a user's natural-language query should be routed to Siri or to a GPT-based ...
Model Shot Success by Location
This question evaluates a candidate's skill in spatial probabilistic modeling, feature engineering, calibration, uncertainty quantification, and handl...
Identify a classic bagging algorithm
Identify a classic bagging algorithm Multiple choice: Bagging Which of the following algorithms is a classic example of bagging (bootstrap aggregating...
Slopes of y-on-x vs x-on-y Regression: Relationship and When They Are Equal
You fit two simple ordinary least squares (OLS) regressions, each with an intercept, on the same paired dataset $(x_i, y_i)$ for $i = 1, \dots, n$: 1....
Construct a Churn-Prediction Pipeline Using Scikit-Learn
Construct a Churn-Prediction Pipeline in scikit-learn Scenario You are a data scientist on a subscription business. You need to build a model that pre...
Detect Data Leakage in Supervised Learning Pipelines
Detect Data Leakage in Supervised Learning Pipelines ML Take‑home: Bias–Variance, Regularization, Leakage, and From‑scratch Logistic Regression Contex...
Choose Between Precision and Recall for a Classification Decision
A binary classifier will support a real decision, and the model produces a probability score for each observation. Explain precision and recall, how t...
Build a predictive model from TurboTax sample data
Build a predictive model from TurboTax sample data evaluates core ML concepts, assumptions, math intuition, training/evaluation trade-offs, and practi...
Explain futures pricing and linear regression basics
You are interviewing for a quantitative/strats role. The interviewer asks a series of theoretical questions about derivatives pricing and linear regre...
Design a CVR model for RTB bidding
Question You are a data scientist at a Demand-Side Platform (DSP) such as The Trade Desk, participating in Real-Time Bidding (RTB). For each ad opport...
Coin-Flip Race to Four: Game Length and a Conditional Win Probability
Two players play a coin-flipping game with a single fair coin. The coin is flipped once per round. Every heads counts for Player 1, and every tails co...
Test whether samples follow a binomial distribution
This question evaluates a candidate's understanding of statistical hypothesis testing, goodness-of-fit assessment for discrete distributions, paramete...
Deploy multi-armed bandits safely
Online bandit with 3 variants, churn guardrail, and delayed conversions Context You are running an online experiment with 3 variants (including contro...
Explain RF optimization and variable-importance pitfalls
Optimize and Regularize a Random Forest Regressor for Tabular Data Context: You are training a Random Forest (RF) regressor on tabular data and need t...