New post: Comparing people from two surveys, one of which is a simple random sample and one of which is not: Jul... http://bit.ly/VISWFP
6:55 AM - 6 Oct 2012
0 replies
0 retweets
2 likes
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.