Now, Khan occasionally uses a simulator in his statistics presentations to demonstrate things like "central tendency" and sampling distributions. Of course, it's all free and available to anyone. The simulations are part of an entire introductory level course in statistics for the practical minded at "online statistics book", an 'interactive multimedia course of instruction'.
I have tried the demonstration/simulation of the hazards of doing arithmetic on ordinal numbers. This demonstration is fully interactive and is very instructive of what we've preached here before many times.
And, there are self tests included.
If've you got an interest in using some clever interactive tools to sharpen your understanding of some of the statistical concepts that project managers run into everyday, give onlinestastbook.com a look
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