Lately, I have given a couple of interviews for Integrated Ph.D. programs in Physical Science. On some I was selected, while on others I was rejected. But I find only trifling differences between these interviews. Whenever I gave answers, they'd say, good and so on. I gave all of the questions asked, a similar response. I don't quite understand how they actually selected the candidate then?
The ones where I'm not selected are the important ones for me, I have another chance and I don't want a similar case as before. If they give a similar response, I have no way of knowing, if what's going on?
So is it all right if I mail them and ask why they didn't select me? Is it appropriate to ask something like that? I just want to improve my chances, that's all.