Interview (management school)

had an interview at management school for a data analysis and evaluation position. Was a bit nervous, but presentation went down well. Interview was hard, but not unreasonable. I am kicking myself for not having a good response to a couple of questions. I'm still not interviewing fluently, just seem to lose any semblance of eloquence. Specifically was asked about chi-squared, and just went blank really, it just a statistical test for goodness sake. I have since thought of at least 5 good responses, only one of which needed additional info to what I had at hand.