This site gives a definition and an example of numerical summaries. Topics include mean, median, quantiles, variance, and standard deviation.
This page generates a graph of the sampling distribution of the difference between two means and displays the probabilities associated with that distribution. Users enter the population standard deviation and the sample sizes, Na and Nb. The applet also calculates the standard error of the sample mean difference.
This page generates a graph of the sampling distribution of r, the Pearson correlation coefficient. Upon opening, the applet prompts for sample size greater than 6. The applet also displays the probabilities associated with the distribution.
Generate a graphic and numerical display of the properties of the t-distribution for values of df between 4 and 200, inclusive.