# Multivariate Quantitative Relationships

• ### Cartoon: Statistical Movies

A cartoon to teach about the importance of providing measures of error, like the Margin-of-Error, with estimates. 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: Confidence

A cartoon to teach about the interpretation of confidence in inference. 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: Professor's Directions

A cartoon for teaching that confidence intervals do not always contain the true parameter. 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: Airport Security

Cartoon by John Landers (www.landers.co.uk) based on a joke popularized on the internet in 2003 soon after the start of the Iraq war (usage of this pun was rare before Jeff Gabbage's October 12, 2003 article, "She's developed weapons of math instruction" in the "Philadelphia Inquirer."). Cartoon is free to use in the classroom and on course web sites.
• ### Brownian Motion Applet

This applet draws one-dimensional Brownian motion. Click the mouse in the window to start zooming. Click again to stop. Since Brownian motion is self-similar in law, all of the zoomed pictures look the same.
• ### 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.

• ### Kolmogorov-Smirnov Test (with Calculator)

This page introduces the Kolmogorov-Smirnov test, gives background and procedures for the test, and provides a calculation page which allows users to enter their own data and perform the test.