DRW Data Scientist Interview Questions
Master your tech interview with our curated database of real questions from top companies.
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...
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 \(X,Y,Z\),...
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 ...
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 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...
Derive eigenvalues and sum for inverse matrix
Eigenvalues of an Inverse and Their Sum Context Let A be an invertible n×n matrix (over the real or complex numbers). All eigenvalues of A are nonzero...
Compute Markov steady state and expectations
Probability and Game Theory: Three Sub-questions Context: The exact transition matrix P (for Q1) and the 2×2 payoff matrix (for Q3) are not provided. ...