Very disappointing experience from interviewing with FB. Absolute worst and least professional interviewer I have ever had.
* FB does video interviews for the first round (along with coding in an online environment). This is fairly surprising since it can't serve much legitimate purpose. I'm sure their legal team is thrilled at the additional burden they face in discrimination lawsuits since the interviewer clearly can has information about the appearance of the candidate and they can't plead ignorance. Of course perhaps they are looking for unkempt candidates or trying to demonstrate the culture of transparency at Facebook, but read on!
* Interview was 5 minutes late to video interview and had disheveled appearance during whole interview. He was constantly fidgeting and playing with the neighboring chairs and objects on the table and even put his feet on the other chairs and table! An interview for a position is a two-way street, so the interviewer also needs to be on "best behavior".
* In addition to the behavior above which was unprofessional, he interrupted very frequently. This goes beyond steering the conversation. This is really tricky since one person is judging you, nobody wants to say "Please allow me to finish explaining my answer and reasoning" and hope somebody like this won't hold it against you. He possibly spent just as much time talking as I did during the interview answering his questions. The interruptions came both in the coding sections when I explained my thought process before implementing it and during the product questions when explaining possible scenarios. Of course clarifying comments are helpful to make sure the candidate is on the right track, but interrupting somebody just because they want to use a subquery (and you wouldn't) and is going to solve the problem slightly differently than you would is indicative of your lack of emotional intelligence and perhaps also the programming language you're working with.
* He obviously wasn't paying attention during the process and didn't take it seriously. He was constantly working on his computer. Of course he could have been taking notes, but after I answered a question twice and explained my thoughts twice, he stated what the correct answer was--which was in fact what I said twice, but he apparently hadn't been listening then and was occupied with the chair/table objects/computer.
* The interviewer seemed to only accept very specific answers that aligned with his thoughts and preferred answers. This mentality is obviously horrible for open-ended questions like "what could be causing this" or "what data would you look at". You may be looking at this data all the time and know which fields are useful for this task, but when you condescendingly react like the interviewee is a complete idiot for thinking of looking at the timestamp patterns for app usage you don't demonstrate your intelligence but rather your closed mindedness and unfamiliarity and inexperience with working with any type of data except the dataset at your company.
* It is probably clear from reading the interview questions from other candidates and what the recruiters provide you as prep, but this really isn't a data scientist position: it's more or a data analyst or SQL monkey position. For this reason I was borderline on interviewing here anyway but thought, "hey, it is Facebook". I'm sure everybody in the industry knows that this is what FB data scientists do, so while the name cache might carry advantages when looking for a job later, it could actually harm you if you want to be thought of as a data scientist and move on to legit data scientist/software engineer positions.
* The information you receive that you can solve the questions in SQL or Python or R is possibly incorrect. My interviewer wanted it in SQL or Python. Not a big deal since I know all three, but when when this is one of the first things you hear (along with all the rest of the insanity of this interview) it is enough to throw you off your game. SQL seems to be the preferred solution, so I'd recommend forgetting about the others if your SQL is decent.
* The one positive of all of this experience is that the recruiters were professional--both in scheduling the interviews and in explaining the role and answering any questions you may have.
Overall, I agree with some of the other comments here that you might get unluckly with a very egotistical interviewer. Officially I haven't heard back from FB yet, but I would be shocked to advance and really have no interest to work with someone like this. Bad apples exist in all companies, but a bro culture like this really does dampen any interest of anything FB. Yikes.
