I’ve added both an HTML and an R notebook version of the simple drift simulation I showed in class so that you can play with it on your own if you don’t want to bother with the snazzier online version. I’ve also added a simulation you can play with to convince yourself that there’s no directional tendency for allele frequencies using sampling from a binomial distribution. Both are linked to from the lecture detail page.
By the way, I tried the snazzy online version that wasn’t updating properly, and it worked this time. As you can see below, when I set the population size to 1000, the allele frequencies change, but not nearly as much as when the population size is only 100 (or 10).