Blizzard Entertainment Data Scientist Interview Questions

HR interview, introduce yourself, projects, ask knowledge domain, interviewer is very friendly, and introduced job description and following interview processes, and team situation. And ask some routine questions afterwards. That is pretty much it

The first round was a screening interview. A recruiter called me and asked a few questions. The second round was a hacker rank coding exercise. The phone screening was fairly straight forward. The hacker-rank had basic array and string questions.

My interview was in four parts: HR screen, technical phone, coding phone, on-site. The HR screen was just a quick discussion about the role and how your experience might apply to it. The technical phone interview consisted of two senior data scientists asking a case study question and how I would approach it. They asked many follow-up questions about my chosen approach and algorithm (to give you an idea of the depth, I eventually had to explain how feature importances in tree-based ensemble models are calculated). The next part was a coding phone interview done on codeshare. Two more senior data scientists asked me to write a simple distance metric and then a common machine learning algorithm that utilized it. I had my choice of R or Python, and they asked me not to use any packages (actually, they took exception to my usage of even some base R functions). They then asked me to calculate the time complexity of my algorithm (I was asked to do this many times throughout the course of my interview process). Next was the on-site. This consisted of a technical interview (basically the in-person equivalent of the technical phone), a whiteboard coding interview (basically the in-person equivalent of the coding phone), "lunch" with two hiring managers (basically an eating interview), a tour of the campus, and a final interview with a high-level manager. This process for me took a little over five hours. My general impressions of the company were: 1. Everyone there seemed very smart and capable, and for the most part were enjoyable to interview with. Every data scientist I interviewed with had a PhD. You can tell you'd learn a ton there in any technical role. 2. How committed you are to gaming is very important to them. I am not a gamer, and practically everyone I interviewed with seemed confused about why I would want to work there given that that was the case (and relatively unconvinced with my non-"because I love blizzard games" reasons), so this continually generated awkward moments and seemed to generally play negatively against me. If you are not a gamer, it's not likely the culture will fit you very well. Expect everyone you talk to to ask you about your gaming history.

HR phone call, easy check up. Set up an hr technical interview. Two Data Scientists on the phone interview asked basic background questions, comfortability with certain tools (R/Python). Then set up a case study for an analysis: given access to their data how to build a model to predict customer value, asked what to do in the case of over/underfitting. Seemed to go well, the last question was on the computational complexity of gradient descent (wtf) which i couldn't answer off the top of my head, and imo is a pretty bad question to ask of a data scientist. didn't get an offer nor even a "thanks but no thanks" from the HR recruiter. pretty unprofessional