
September 16, 2026
A strong CV can tell you where a quant candidate studied, which firms they worked for, what programming languages they know, and which projects they completed. It cannot tell you how they approach a problem they have never seen before.
That distinction matters in quantitative hiring. Strong credentials are useful signals, but they do not necessarily show how someone works with uncertainty, tests a hypothesis, responds when an idea fails, or explains a complicated problem to other people.
This is why evaluating quant talent requires looking beyond the CV.
A technical interview should reveal more than whether a candidate reaches the correct answer. The way they approach the problem can be just as important.
Give candidates a problem with incomplete information and observe what they do. Do they clarify the assumptions first? Can they break the problem into smaller parts? Do they recognize when an approach is failing and try something else?
This is closer to real quantitative work than testing whether someone can reproduce a familiar solution. Research problems rarely arrive with a clean specification and a known answer.
Leading quant firms use similar principles in their hiring. Jane Street emphasizes collaborative problem solving and says it is interested in how candidates think and learn. Citadel also evaluates problem-solving and research ability alongside technical skills.
Knowing statistical formulas is different from knowing when to trust the results.
Quant candidates need to be comfortable with uncertainty, noisy data, changing relationships, and limited samples. They should understand why a result that looks impressive in a backtest may not survive outside the original dataset.
One way to test this is to present a strategy or model with unusually strong historical performance and ask what the candidate would investigate before trusting it.
The discussion might include sample size, overfitting, data leakage, transaction costs, regime dependence, or out-of-sample testing. The exact list is less important than whether the candidate instinctively questions the result and knows how to investigate it.
When discussing previous projects, focus on how the candidate reached the result rather than only on the final outcome.
Ask about the original hypothesis, the data they used, the assumptions they made, and what happened when the first approach did not work. How did they decide whether to continue, modify, or abandon the idea?
Failed research can be particularly informative. Quantitative research inevitably produces hypotheses that do not survive testing. A candidate who can explain why an idea failed and what they learned from it may demonstrate stronger research judgment than someone who presents only successful projects.
You can also introduce new information during the interview. Change the size of the dataset, increase transaction costs, or tell the candidate that the relationship disappears during volatile periods. Their response shows whether they can update their approach when the evidence changes.
Coding assessments are useful, but speed should not be the only thing being measured.
A realistic task involving data can reveal how a candidate structures a problem, checks the input, handles edge cases, validates the output, and explains technical decisions.
The assessment should also reflect the actual role. A quant researcher may need strong Python, statistics, and data-analysis skills. A quant developer may require deeper knowledge of algorithms, systems, performance, and production infrastructure. A quant trader may need a different combination of quantitative reasoning, market intuition, and coding.
Testing candidates on work that resembles the job provides more useful information than an isolated programming exercise.
Quantitative work is technical, but it is rarely isolated.
Researchers work with traders and developers. Developers need to understand the models they are implementing. Trading teams need to discuss risk, execution, performance, and unexpected model behavior.
A candidate should therefore be able to explain a complicated idea clearly, including its assumptions and limitations.
One simple test is to ask them to explain a previous project to someone outside their specialization. Deep understanding often becomes visible when a person can simplify an idea without losing its meaning.
Communication is also part of the hiring criteria at major quantitative firms. Jane Street, for example, highlights precise communication and collaboration alongside quantitative problem solving.
There is no single profile for a successful quant candidate. Academic background, previous employers, publications, competitions, and technical skills can all provide useful signals, but they are only the starting point.
A good hiring process gives candidates opportunities to demonstrate how they solve unfamiliar problems, work with data, test hypotheses, write code, communicate their reasoning, and respond when new evidence challenges their original approach.
A CV shows what a candidate has done. The interview should help you understand how they work.