Rigorous analytical Questions asked by interviewers who are typically physicists, mathematician, computer scientists. The interviews are rigorous and not easy. People are tying to make sure that you can operate at a very high level.

Not the typical type of interview, have asked a lot of time series related math questions, correlations and such, even though I come from a computer science major. Questions are not taylored to you personally I guess, should prepare every aspect including C, python, statistics and many more. Got rejected pretty quick.