v.3.02a  20th September-2006-  The zipped file is 10Mb in size and is named ttest302a_setup.zip. It can be downloaded here. The program implements a standard independent means t-test on data where you only have access to the mean, sd, and n for each sample. It also computes the Fisher homogeneity of variance test and outputs the results for both homogenous and non-homogenous variance t-tests, along with Cohen's d and eta-square effect size under homogeneity and non-homogeneity conditions. The "publication-ready" results can be printed, pasted from the clipboard direct into a Word Processor document, or saved into an rtf format file. A large help file (on-line) which explains how to use it and defines the formulae and procedures used accompanies the program. I've also included much background information and advice about the wisdom of testing the homogeneity of variances. Single or multiple t-tests (with Bonferroni probability computed) can now be undertaken with the program, with data entry from the keyboard or via Excel or csv textfile input. The installation fileset includes three test files (2 x Excel and 1 x csv format) to get you started.

Version 3.01 (April 2006) corrects the status-bar description for the program, the formula for Cohen's d in the Help file, and some component calculation labels on the main screen. Nothing dramatic but the labels and relevant help-file section on Cohen's d  needed clearing up for the sake of correctness. Screen images have been updated in the help file.

Version 3.02 (September 2006) corrects for the menu graphics being incorrectly referenced to the "current" directory instead of the install directory. This meant you couldn't access the reports unless your analysis file happened to be in the installation directory. Sigh ... we live and learn!

Version 3.02a (September 2006) provides much more information in the help-file regarding the Welch-Satterthwaite and Welch adjusted degrees of freedom, including a new example - and brings attention to the issue of computing effect sizes using the Welch-corrected degrees of freedom. No changes made to the program.

* Important note. If you still have t-test v. 2.1 installed, you will need to uninstall it (remove it) prior to installing v. 3.0 (use Add/Remove programs).

An audio-visual (AV) tutorial file accompanies the program - which walks you through all the program functions and output. The 145 slide tutorial lasts 16 minutes, 16 seconds - and may either be downloaded as an executable file (in a zipped archive) which can be run on your own machine, or you can run the AV tutorial directly from the web, using the Macromedia Flash version of the tutorial.

Download standalone AV tutorial file here (145 slides, 16 minutes, 8.2Mb). Remember to unzip the archive and run the executable file.

Run the tutorial online tutorial from here.

Download and Installation Information
You can run the setup file from the web-page download dialog, or save it to some convenient location on your own disk and simply run the setup file. The software can be installed in any directory of your choosing.