I applied online. They contacted me after a couple weeks to request an interview. No phone interview, which I thought was curious. The interview itself was meeting with someone from HR to discuss the job, benefits, etc.. This was followed by 3 interviews, each with 2 economists from different sections. The questions were not different from a typical interview, though certainly more focused toward research and coursework. They're most interested in research experience, coding experience, and economic/math knowledge, with most of the focus on the first two. Lunch was with 3 current RAs, who were able to answer questions and give an idea of the day-to-day of RAs.