PRACTICE GUIDE D. E. SHAW
D. E. Shaw Technical: what the test is, and how to train for it
The D. E. Shaw technical screen is 12 questions in 17 minutes - about 85 seconds each - answered by picking one of the options. It marks negatively, so a wrong answer costs you a mark and a skip costs you nothing.
Where it sits: Technical section of the campus test. The practice sitting on this page runs the same item count, the same clock and the same marking rule, with questions generated by Outcry rather than taken from D. E. Shaw.
Outcry is not affiliated with D. E. Shaw and has no access to their assessment content. This guide describes an assessment format that candidates report publicly; the questions here are generated by Outcry and are not D. E. Shaw’s own.
What it screens
A quantitative investment firm based in New York, among the largest and longest-running in the industry.
- ✓Reading concurrent code and pointing at the defective line
- ✓Order-book data structures: what happens on a cross, a cancel, a partial fill
- ✓Algorithmic complexity chosen for the input sizes stated in the problem
- ✓Monte Carlo methods and when a simulation beats a closed form
Where it sits at D. E. Shaw
This section does not arrive on its own. It is section B of 4, and the sitting around it runs 95 minutes and 28 items in total, with Aptitude, Coding problem 1 and Coding problem 2 on the same continuous clock. Candidates who prepare only for this round tend to be caught by the pacing of the rest.
There is no going back. You answer or skip, and the next item loads, which means the decision to leave an item is final at the moment you make it.
The format
These are the numbers the D. E. Shaw sitting on this site runs on, matching the format candidates report.
| Questions | 12 |
|---|---|
| Time | 17 minutes |
| Per question | 85 seconds |
| Negative marking | Yes - a wrong answer costs a mark |
| Answer style | Multiple choice |
| Where it sits | Technical section of the campus test |
What it tests, with a worked example
Every example below is generated by Outcry, drawn from the same question generators the timed drills run. None of them is D. E. Shaw’s.
Data structure implementation
Build the thing rather than call it: an order book, a cache, a ring buffer. Graded by hidden tests, so there is no partial credit for an approach.
Language and systems detail
Memory, references, undefined behaviour and the things that bite in production.
Example
A table holds 229,000 rows of 256 bytes each. Blocks are 4,096 bytes and rows do not span blocks. How many blocks does a full scan read?
- 14,313
- 229,000
- 218,000
- 16
Answer 14,313
4,096 / 256 = 16 rows a block once the remainder is discarded, since a row cannot straddle a block. 229,000 / 16 rounds up to 14,313 blocks. Dividing total bytes by block size gives 14,313 and quietly assumes no wasted tail.
Numerical and data handling
Floating point, aggregation and joins on data that does not fit the obvious shape.
Example
X and Y are independent, with standard deviations 17 and 30. What is the correlation between X and X + Y?
Answer 0.49301257198088033
Cov(X, X+Y) = Var(X) = 289, because X and Y are independent. SD(X+Y) = sqrt(289 + 900) = 34.482. So the correlation is 289 / (17 x 34.482) = 0.493. Adding independent noise to a series never makes the correlation zero, only smaller.
Edge cases
Empty input, one element, duplicates and overflow. The hidden tests always include them.
Probability behind the problem
Screens that look like coding questions and are really expectation questions.
Example
A strategy returns 19.8% a year with an annual volatility of 27.8%. Cash pays 3.7%. What is its Sharpe ratio?
Answer 0.579
Sharpe is excess return per unit of risk: (19.8% - 3.7%) / 27.8% = 16.1% / 27.8% = 0.579. The risk-free rate has to come out of the numerator, because holding cash earns 3.7% at zero volatility and no strategy should get credit for that. Using the raw 19.8% gives 0.712, which flatters the strategy by 0.133 and flatters it more the higher rates go.
Reading a spec precisely
Return type, ordering and tie-breaking are graded, and are where most silent failures come from.
What a good score looks like
On a paper of 12 questions marked +1 and -1, the arithmetic of the threshold matters as much as the threshold: every wrong answer costs you two places against someone who skipped it. Coding screens are usually pass-fail on hidden tests rather than scored, and candidates commonly report that a solution passing every correctness test still fails on a timeout. Treat full marks as solving every problem inside the complexity bound, not merely solving it.
How to train for it
- 01Implement the core structures from scratch once each. The screens ask you to build them, not use them.
- 02Write the edge cases into your own tests first. That is where the hidden ones live.
- 03Get the function signature exactly right before anything else. Return type and ordering are graded, and a correct algorithm behind a wrong signature scores zero.
TRAIN IT HERE
The drills that match each section
Concurrency Clash
Find the data race, name the fix - real C++ defect patterns, five levels.
Order Book
Matching-engine mechanics: crosses, cancels and partial fills.
Algorithm Lab
DP tables, Monte Carlo estimation and speed rounds at four difficulty tiers.
SIT THE FULL BATTERY
All the sections back to back on one clock, marked the way the real screen marks them, with a by-skill breakdown at the end. Included with any pass.
Also reported at D. E. Shaw
Common questions
- Is the D. E. Shaw technical test multiple choice?
- Multiple choice. You pick one option per question.
- How long is the D. E. Shaw technical test?
- 12 questions in 17 minutes, which is about 85 seconds each.
- Is there negative marking on the D. E. Shaw technical test?
- Yes. A wrong answer costs you a mark, so an item you cannot see a route through is worth skipping outright - a blind guess on this paper is negative expected value.
- How do I practise for it free?
- Every drill linked on this page is free to play, with no account, inside a daily run cap. Questions are generated fresh each run, so there is nothing to memorise between attempts. The full D. E. Shaw India Campus Online Test sitting puts the sections back to back on one clock.