There was some misunderstanding in terms of communicating the duty of the job. One guy told me that the position would be very interesting since it needs strong quantitative and statistics. But during the phone interview after that, the interviewer asked me questions which basically was calculation without calculator. On the other hand, when I was using "expectation value" or "partial derivative", the interviewer seemed to have never heard of these terms.
1) Phone screen with the Recruiter, where she shared a little about the company/role/culture, and asked a few basic questions about me. 2) Homework assignment sent by the Recruiter, and afterwards - would get a response if you move to the next round (phone screen with the Hiring Manager). Unfortunately, after I submitted my homework assignment, the Recruiter completely "ghosted" on me and didn't respond to any of my 3 follow up emails asking for an update. I figured I didn't get it, but this was just an annoying experience.
