One Numerical Variable

• Cartoon: Markov chain Monte Carlo Diagnostics

A cartoon to teach about the importance of diagnostics in Markoc chain Monte Carlo procedures. Cartoon by John Landers (www.landers.co.uk) based on an idea from Dennis Pearl (The Ohio State University). Free to use in the classroom and on course web sites.
• Cartoon: The T-Test vs The Sign Test

A cartoon to teach about comparing parametric versus non-parametric inference. Cartoon by John Landers (www.landers.co.uk) based on an idea from "Lower Bounds on Statistical Humor" by Alan H. Feiveson, Mark Eakin, and Richard Alldredge. Free to use in the classroom and on course web sites.
• Kruskal-Wallis Test

This tutorial on the Kruskal-Wallis test includes its definition, assumptions, characteristics, and hypotheses as well as procedures for graphical comparisons. An example using output from the WINKS software is given, but those without the software can still use the tutorial. An exercise is given at the end that can be done with any statistical software package.
• Body Measures: Exploring Distributions and Graphs Using Cooperative Learning

Using cooperative learning methods, this lesson introduces distributions for univariate data, emphasizing how distributions help us visualize central tendencies and variability. Students collect real data on head circumference and hand span, then describe the distributions in terms of shape, center, and spread. The lesson moves from informal to more technically appropriate descriptions of distributions.
• Understanding the standard deviation: What makes it larger or smaller?

Using cooperative learning methods, this activity helps students develop a better intuitive understanding of what is meant by variability in statistics. Emphasis is placed on the standard deviation as a measure of variability. This lesson also helps students to discover that the standard deviation is a measure of the density of values about the mean of a distribution. As such, students become more aware of how clusters, gaps, and extreme values affect the standard deviation.
• Graphical Table of Normal Distribution

This applet relates the pdf of the Normal distribution to the cdf of the Normal distribution. The graph of the cdf is shown above with the pdf shown below. Click "Move" and the scroll bar will advance across the graph highlighting the area under the pdf in red. The z-score is shown as well as the probability less than z (F(z)) and the probability greater than z (1-F(z)).
• Analysis Tool: HyperStat Online Statistical Analysis (Descriptive Statistics)

This page computes a variety of descriptive statistics and creates a stem and leaf plot. Enter data in the text area, specify a delimiter (Space, Return, Tab, New line), and click "Compute". The page returns sample size, mean, median, trimmed mean, trimean, minimum, maximum, range, first quartile, third quartile, semi-interquartile range, standard deviation, variance, standard error of the mean, skew, and kurtosis. Key Word: Calculator; Summary Statistics.

• A New View of Statistics

This online resource is intended to help students understand concepts from probability and statistics and covers many topics from introductory to advanced. You can follow the progression of the text, or you can click on a topic on the left. Key Words: Alpha Reliability; Analysis of Covariance (ANCOVA); Analysis of Variance (ANOVA); Bayesian Analysis; Bias; Binomial regression; Bonferroni adjustment; Bootstrapping; Categorical modeling; Central limit theorem; Chi-squared test; Clinical significance; Cluster analysis; Coefficient of variation; Confidence Intervals; Contingency Table; Controlled trial; Confounders; Correlation; Dimension reduction; Discriminant function analysis; Frequency; Normal; Poisson; Probability Distribution; Effect; Error; Factor Analysis; Goodness of Fit; Heteroscedasticity; Hypothesis Testing; Independence, Interactions; Kappa Coefficient; Latin Squares; Least Squares Means; Likert scales; Linear Regression; Logistic Regression; Multivariate ANOVA (MANOVA); Mixed Modeling; Multiple Linear Regression; Nonparametric models; Odds ratio; P Values; Path Analysis; Percentiles; Polynomial Regression; Power; PRESS; Probability; Relative Frequency; Repeated Measures; Sample Size; Sampling; Sensitivity; Stepwise regression; Structural equation modeling; T Test; Transformation; Validity.
• The Sign Test

This tutorial explains the theory and use of the Sign Test and demonstrates it with an example on intervention methods. Data is given as well as SPSS and Minitab code.
• Wilcoxon Matched-Pairs Signed Ranks Test

This tutorial explains the theory and use of the Wilcoxon Matched-Pairs Ranks test and demonstrates it with an example on project quality. Data is given as well as SPSS and Minitab code.