I wasn't aiming to answer Locaha's question as much as figure out what question to answer. The range of math knowledge here is high, and I don't know where Locaha stands. I mean,

But why [is the mean calculated as] sum/n?

That could be a basic question about the meaning of averages -- the sort of knowledge I internalized so deeply that I have trouble forming it into words.

But maybe Locaha's asking a question like:

Why is an unbiased estimator of population mean a sum/n, but an unbiased estimator of population variance a sum/(n-1)?

That's a less philo... (read more)

Open thread, January 25- February 1

by NancyLebovitz 1 min read25th Jan 2014318 comments


If it's worth saying, but not worth its own post (even in Discussion), then it goes here.