This site focuses on using the LRT to compare two competing models.
This page gives a description of correlation, Pearson's r, Spearman's rho. There are some scatterplots illustrating the different values of r.
The page calculates summary statistics for any dataset. Users will be prompted for sample size when opening this page. The calculator returns mean, sum of X, sum of X^2, variance, standard deviation, and standard error. Key word: Descriptive statistics.