The interviews had barely had anything to do with Data Science, mainly coding and received a negative feedback about a code speed up question. I think I achieved 3-4 order of magnitude speed up that as a feedback I heared it was not good??? They asked me about a random processies question which I doubt interviewer ever taken an advanced statistics course. I took an screen shot and shared it with them so they know how bad it was. The engineers were professional, but this was a software engineering interview and had nothing to do with DATA SCIENCE. It was 20 hours spent for preparation and interview to learn barely anything, and feel bad at the end for the lack of planning/poor judgment.