While certainly an open ended question for you to run with, your interviewer is really looking to get a sense that you are resourceful in your decision making processes and that you don't rely too heavy on quantitative or qualitative information to make decisions. In your answer, talk about the sound use of data while also relying on your experience and judgement to help in your decision making processes. As well, if you are open and experienced in a team based approach among fellow colleagues, talk about that as well.