Tools
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Statistics lab
Draw thousands of samples and watch the central limit theorem, confidence intervals, hypothesis tests and regression at work.
Probability explorer
Move the parameters of fourteen distributions and watch the pmf, pdf and cdf change, with exact probabilities and a live simulation.
Statistical tables
Normal, t, chi-square and F tables, with a lookup for any value, area or degrees of freedom.
Counting toolkit
Exact binomial and multinomial coefficients, Stirling, Bell and Catalan numbers, derangements and partitions.
Formula sheets
One-page formula sheets for a course, with a quick drill to make them stick.