DRW Interview Questions
Master your tech interview with our curated database of real questions from top companies.
Train LinearSVC to beat baseline accuracy
Task: Train and Evaluate a LinearSVC to Beat a Baseline Context You are given a binary or multi-class classification dataset split into train and hidd...
Analyze distribution of a 3-dice product
You roll three independent fair 10-sided dice. Each die shows an integer in \(\{0,1,\dots,9\}\) with equal probability. Let the outcomes be \(X,Y,Z\),...
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...
Solve three algorithmic OA problems
You are given three independent coding problems. --- Problem 1 – Knockout Tournament Match Counts There are \(n\) players standing in a line, indexed ...
Differentiate sample vs population standard deviation
Population vs. Sample Standard Deviation in a Finite Rolling Window Context You are implementing a rolling standard deviation over a fixed-size window...
Compute rolling standard deviation in O(n)
Given an array of numbers and a window size k, compute the rolling standard deviation for every contiguous window. Design an O(n) algorithm that updat...
Solve movie ratings, array, release scheduler
Question LeetCode 135. Candy – Distribute the minimum number of candies (stars) so that each movie gets at least one star and any movie with a higher ...
Implement portfolio optimization simulation
Question Given price-return time series in a DataFrame, simulate random portfolio weights, compute expected return, volatility, Sharpe ratio, and retu...
Build pipeline for imbalanced classification
Build an Imbalanced Classification Pipeline (scikit-learn + imbalanced-learn) Context You are given a tabular dataset with a severely imbalanced binar...
Solve odd-string, digit swap, patient slot assignment
Question Task 1 – Odd-occurrence string: Write a function that, given an integer N (1..200 000), returns a length-N lowercase string in which every le...
Explain core ML concepts
ML Theory Check: PCA, Trees, RL, Regularization, Optimization, and Transformers Context: Provide concise, technically correct explanations suitable fo...
Solve Markov and distribution expectation problems
Statistics, Linear Algebra, and Game Theory Fundamentals 1) Stationary Distribution of a Finite Markov Chain Given a finite Markov chain with transiti...
Solve three algorithmic OA tasks
Task 1 (Odd-frequency string): Given an integer N in [1..200000], write an algorithm that returns any length-N string of lowercase letters (a–z) such ...
Build an imbalanced classification pipeline with sklearn
Take-home: End-to-end Imbalanced Binary Classification Pipeline (scikit-learn + imbalanced-learn) Context You are given a tabular, imbalanced binary c...
Implement simulation-based portfolio optimizer in Python
Given a pandas DataFrame 'returns' of daily asset returns (index: dates; columns: tickers) and an annualized risk‑free rate r_f, implement a simulatio...
Explain core ML and DL fundamentals
ML/DL Concept Questions (Take‑home) Provide concise, correct answers to each prompt. 1) PCA - What do the eigenvectors of the covariance matrix repres...
Train LinearSVC to beat a hidden baseline
Take‑Home: Build a strong LinearSVC pipeline that beats a baseline and generalizes Problem You are given training features X_train and labels y_train ...
Process CSV for portfolio returns and metrics
Given one or more CSV files containing daily asset prices or returns and optional portfolio weights, write Python (pandas) code to: a) load, clean, an...
Explain Transformers, activations, and training optimization
Modern Deep Learning: Conceptual Questions (ML Engineer Take-home) You are preparing for a Machine Learning Engineer take-home. Answer the following c...
Solve three algorithmic tasks in Python
Implement in Python three tasks. 1) Movie Ratings (DP): Given an integer array ratings of length n, return both (a) the length of the longest strictly...