StumbleUpon Data Science interview questions

An initial phone call with the HR to fix the date and time, followed by an hour telephonic interview. There was no coding challenge. The interviewer asked questions based on the resume. I was asked questions on statistics, probability, data mining, some graph theory. Most of the questions were from a design perspective and scalability to big data. The interview went for more than the allocated time and the interviewer still was happy to answer any questions about work at StumbleUpon. I got a call back with my interview feedback in a couple of weeks and got my offer letter another week after that.