The whole process took most of the month of October. 1st round was a campus interview at my university. It was 1 hour long with two people, one who took most of the notes on one computer and another who did most of the talking. It was mostly behavioral style interview questions. The hour time slot left lots of time for me to get detailed in my answers and for them to ask follow up questions, so it was more like a conversation than most interviews I've been on. They also left time for me to ask questions of my own, so be sure to have some good ones ready.
Final round interviews were held in Tampa FL over a two day time period. They gave me less than 2 weeks notice for the final round, so if you have a job with a set schedule that could be a problem. Nielsen covered all travel expenses including airfare, hotel, and food. First day, Wednesday, was meet and greets, a couple of talks be Nielsen representatives, and a game. The next day, Thursday, you have 3 interviews, a technical interview, case interview, and a team challenge, along with some more talks and panels after the interviews.
Case interview: materials are very dense and are sent out around a week before, read them well because there's no telling what you'll be asked about specifically, but if you've read it all and understood it you will be able to comment on whatever parts they question you on.
Technical interview: They gave the data science interviewees an additional packet at check-in on the first day that we needed for the technical interview. (ETP - Technology interviewees did not get an additional packet and were asked more specific coding questions.) There wasn't much time for looking it over the night before, but it was worth it to do so because my interviewer was very impressed that I'd already taken notes and had ideas on how I would handle the data for the specific problem posed in the packet. In addition to questions about the packet, they also asked questions about my past experience analyzing data. For both the technical and case interviews you are given plenty of time to answer the questions as in-depth as you'd like.
Team challenge: this one was the easiest and most fun. They assign you to teams of 3 that are in your track (Data Science, Technology, Engineering, etc.) and give you a problem that Nielsen is facing or has faced in the past, and ask your team to come up with a solution and present it. The problem might be something like they need to redesign one of their devices to be smaller and more efficient, but also keep costs low. Just be energetic and enthusiastic, being sure to be a good team player by being equally enthused by your fellow team members' ideas. Don't be afraid to ask the observers/interviewers they have watching you for more details. They leave the question vague and don't give you much info on purpose, however the interviewers don't mind answering a few questions, and the worst they can say is "That would be giving away too much information".
After the Tampa interview they told us to wait 2 to 3 weeks to hear back from them, but they called me the very next day and offered me the position. I had two weeks to give them my answer. The position starts in July, regardless of whether you are graduating in the winter or spring. The offer was made in late October.
