First few rounds are entirely mental math skills based (no writing notes)
Scheduled by HR person but interviews are by traders. Those traders might call a half hour to an hour later than the scheduled time.
The first round is 3 math questions followed by guessing on how correct the previous answers were.
Preguntas de entrevista [1]
Pregunta 1
Which question do you most thing you were wrong about and how wrong were you?
They tend to examine the logical thinkers that can communicate clearly and concisely, and some problem-solving exercises intended to explore how you gather and apply new information, very different from other tech companies' interviews.
Initial application and online assessment. Had a first round behavioral interview where they asked me about myself, my experiences, and a couple of brain teasers. The interviewer was very nice.
Acudí a una entrevista en Jane Street (Londres, Inglaterra)
Entrevista
Phone interviews (at least 3) - questions were of mixed difficulty (some pretty hard) but the interviewers were friendly and they gave helpful hints. Kind of fun - review probability and game-type questions.