I had a phone screener with a recruiter followed by a code review technical interview with members of the analytics team. It went well and they told me I would hear back regardless the following week - never heard back.

I applied for the position online back in late November, and I was contacted by the recruiter who requested unofficial transcripts and a code sample (SAS, R, Python, Stata) for initial review the first week of December. Two weeks later, my recruiter contacted me to set up an introductory phone interview to go over my skills and interests. A week after the screening, I was scheduled for a 1-hour technical interview where I discussed my code sample in detail with two of the hiring managers. About two weeks later, an HR representative set up a 3-hour panel interview where I spoke with 7 different technical individuals. The questions were mostly behavioral and tried to gauge my passion for research and how well fit with the company's culture; however, there was an occasional technical question here and there. Everyone that I interviewed with was very amicable and laid back, which was nice. After the panel interview, the HR rep contacted me and requested permission to contact my references, and two weeks later I received the job offer. Overall, this was the best interview experience that I've ever had. The work that Mathematica does is what initially sparked my interest, but after meeting the team and experiencing the company's streamlined interview process, I was sold on the job.