StatPREP Activities

Each of these documents is an activity that you can do in class, or assign as homework.

Providing links to your students This document tells you how to grab a Word-formatted version of each activity or a web link to a plain HTML document containing the activity.
Jittering Jittering is a graphical technique that extends point plots to make them more informative about categorical variables.
Types of variables Introduces the distinction between quantitative and categorical variables, the *range* of a quantitative variable and the *levels* of a categorical variable.
Experiment and causality Causality as a reason to identify one variable as the response and another as the explanatory.
Shapes of distributions Introduces terms such as skew, bi-modal, and flat, by reference to the difference of the actual variable from a theoretical normal distribution.
What is a confidence interval? Describes the desired behavior of a confidence interval, that is, how to test whether a procedure produces a valid confidence interval.
The two-sample t test Having already looked at the overlap of confidence intervals on the means of two groups, formalizing the process as a t-test.
How much is explained? Using R-squared to quantify how much of the variation in a response variable is accounted for by explanatory variables.
Data and Point Plots Introduces the distinction between quantitative and categorical variables through their very different appearances in a point plot.
Comparing two proportions NOT YET AVAILABLE. Is there evidence that the proportion of a given outcome is different among explanatory groups?
Flexibility NOT YET AVAILABLE. Determine whether a curved or straight-line relationship is a better description of the relationship between two quantitative variables.