Phone call with a trader at the company. They asked some basic probability questions, mostly coin flipping and dice rolling sorts of things. The interviewer was nice and helped if you got stuck.
Jane Street interviews FAQs
Quantitative Trading Interview applicants have rated the interview process at Jane Street with 3 out of 5 (where 5 is the highest level of difficulty) and assessed their interview experience as 100% positive. To compare, the company-average is 63.8% positive. This is according to Glassdoor user ratings.
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