Free. provides everything a big, fat, hard-covered stats book does but it in an easily navigable web format. online book. designed and developed by David Lane at Rice University, with a host of helpful co-authors and funding from the National Science Foundation. All chapters include multiple video presentations on such topics as quantitative variables, histograms, and one-factor ANOVA. This is a great find for anyone who wants to better understand the multitude of fields, from politics to plate tectonics, that depend on statistical modeling.