Is it an internal vacancy? If so, you might have an idea who is being interviewed. If not, it is highly unlikely - jobs aren't so easy to come by nowadays, and if you have no idea of how many applicants there were and their suitability for the job, then you can't say that you were the best qualified. The potential employer has to sift through possibly loads of CVs from people who all think they're best qualified and they have to pick out the applications that look best to them. It's the luck of the draw, really.