Interviewed first over the phone. Nature of the call was mostly to see if I had a quantitative background and to overall "feel" me out. Onsite interview was three hours long. Met up with one analyst and two managers. Was asked to build a demand plan on the spot. The issue is that the interviewer purposefully gave me incomplete information to see if I would ask the correct questions needed in order to build a viable model. I believe they truly just want to see your train of thought.