Visualizing hypothesis tests

Doane, D. P., Mathieson, K., & Tracy, R. L.

Three software modules were created to help students learn to visualize hypothesis tests, based either on scenarios or on a Do-It-Yourself control panel to set up the experiment. The one-sample and two-sample modules illustrate tests of means or variances. For each sample, there is a dot plot with optional overlays of the populations or sampling distributions, table of statistics and parameters, confidence intervals, and theoretical distribution of the test statistic with the rejection region shaded. The ANOVA module offers stacked dot plots, ANOVA table, and sample statistics. Each module allows replication experiments to estimate empirical Type I or II error. There is an extensive help system. Software has been tested on students. The modules are part of an NSF-supported project to enhance quantitative reasoning and motivate students.