An independent, nonpartisan resource on trends in American public opinion. Gives examples of recent polls, margins of error, questions asked, and sample sizes.
A "12 page" tutorial that explores the liner models via excel spreadsheets. The learning module leads the user through various aspects of linear modeling. This tutorial includes a worksheet that allows students to vary the scatter (or noise) level, by adjusting the scroll bar or by clicking on the arrows, to see how the slope and intercept of line respond to the addition of scatter to the data, while monitoring the value of r^2.
This general, introductory tutorial on mathematical modeling (in pdf format) is intended to provide an introduction to the correct analysis of data. It addresses, in an elementary way, those ideas that are important to the effort of distinguishing information from error. This distinction constitutes the central theme of the material described herein. Both deterministic modeling (univariate regression) as well as the (stochastic) modeling of random variables are considered, with emphasis on the latter. No attempt is made to cover every topic of relevance. Instead, attention is focussed on elucidating and illustrating core concepts as they apply to empirical data.
As taken from the web site: "STATGRAPHICS Centurion is designed for anyone who wishes to do serious data analysis without investing weeks learning how to use a statistical package. It contains over 150 statistical procedures, covering everything from summary statistics to design of experiments. Yet you don't need to be a statistician to use the program. Everything is completely menu-driven, and there are tools such as the StatWizard and StatAdvisor to help you use the program most effectively." This program is available in three editions:Standard, Professional, and Enterprise.
PSPP is a statistical analysis program. It is an upwardly compatible replacement of the proprietary statistical analysis program called SPSS. PSPP is a program for statistical analysis of sampled data. It interprets commands in the SPSS language and produces tabular output in ASCII, HTML, or PostScript format.
Statistical modeling software designed for the Macintosh. Performs several operations and gives graphical output.