Resource Library

The number of degrees of freedom is usually self-evident - except for the analysis of data that have not appeared in a textbook. A quote from M.I.T. professor of management David Durand (1912- 1996) Published in a letter to the editor of "The American Statistician" June, 1970 as part of a tongue-in-cheek "Dictionary for Statismagicians." The quote also appears in "Statistically Speaking: A dictionary of quotations" compiled by Carl Gaither and Alma Cavazos-Gaither.

A theory can be proved by an experiment; but no path leads from experiment to the birth of a theory. A quote attributed to Physicist Albert Einstein (1879 - 1955) in the July 18, 1976 issue of "The Sunday Times." The quote also appears in Statistically Speaking: A dictionary of quotations compiled by Carl Gaither and Alma Cavazos-Gaither.

A cartoon for teaching about the key caveats of correlation and regression. Cartoon by John Landers (www.landers.co.uk) based on an idea from Dennis Pearl (The Ohio State University). Free to use in the classroom and on course web sites.

A cartoon using a classic example for teaching the idea that correlation does not imply causation. Cartoon by John Landers (www.landers.co.uk) based on an idea from Dennis Pearl and Deb Rumsey (The Ohio State University). Free to use in the classroom and on course web sites.

This applet draws one-dimensional Brownian motion. Click the mouse in the window to start zooming. Click again to stop. Since Brownian motion is self-similar in law, all of the zoomed pictures look the same.

These pages from the University of Melbourne explain statistical concepts using various examples from medicine, science, sports, and finance. The intent is not computational skill but conceptual understanding. Some pages also contain data.

This collection of tutorials demonstrates various statistical topics with data and provides SPSS and Minitab code. Topics covered: Measures of Central Tendency; Sign Test; Chi-Square; Mann-Whitney Test; Wilcoxon Matched-Pairs Signed-Ranks Test; Kruskal-Wallis One-Way Analysis of Variance; Friedman Two-Way Analysis of Variance; Spearman Rank Correlation; Pearson Product-Moment Correlation; Multiple Regression; t-Test for Independent Samples; t-Test for Matched Pairs; One-Way ANOVA; Two-Way ANOVA.

This tutorial explains the theory and use of Pearson's Product Moment Coefficient of Correlation and demonstrates it with an example on GPA and test scores. Data is given as well as SPSS and Minitab code.

This page helps readers know which statistcal tests are appropriate for the different types of data. Two charts display the information. A discussion of study design and sample size, as well as exercise questions with solutions are also provided.

This applet introduces the concept of confidence intervals. Select an alpha level, sample size, and the number of experiments, and click "Play." For each sample, the applet will show the data points as blue dots and the confidence interval as a red, vertical line. The true population mean is shown as a horizontal purple line, and green ovals indicate which intervals do not contain the true mean.