# Scatterplot

• ### Cartoon: A Fruitful Example

A cartoon suitable for use in teaching about scatterplots and correlation. The cartoon is number 388 (Feb, 2008) from the webcomic series at xkcd.com created by Randall Munroe. Free to use in the classroom and on course web sites under a creative commons attribution-non-commercial 2.5 license.

• ### Song: I Use the Line

Song contains concepts and terms associated with linear regression. May be sung to the tune of "I Walk the Line" (Johnny Cash). Musical accompaniment realization and vocals are by Joshua Lintz from University of Texas at El Paso.

• ### 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.

• ### Normal Approximation to Poisson Distribution

This applet demonstrates the Normal approximation to the Poisson Distribution. Users can set the rate, lambda (‘é), and the number of trials, n, and observe how the shape of the distribution changes. The Poisson distribution is shown in blue, and the Normal distribution is shown in red.
• ### Confidence Intervals

This applet introduces the concept of confidence intervals. Select an alpha level, sample size, and the number of experiments, and click "Play." For each sample, the applet will show the data points as blue dots and the confidence interval as a red, vertical line. The true population mean is shown as a horizontal purple line, and green ovals indicate which intervals do not contain the true mean.
• ### World Development Chart

This scatterplot lets users plot a number of demographic variables and see the log transformation of those variables for numerous countries and income groups. Users can also see the information for any year from 1975 to 2004.
• ### Least Squares Regression Applet

This applet shows a scatterplot of height versus foot length. Users can add or delete points and then guess the regression line by clicking "Your Line" and moving the blue regression line. By clicking "Regression Line" users can see the actual regression line. The applet also shows the correlation and R-square for the data as well as the residuals and squared residuals for the guessed regression line and the actual regression line.
• ### Statistics Formula Reviews

This page contains links to 5 review sheets with formulas, properties, definitions and rules for basic descriptive and inferential statistics and probability concepts. The review pages are in pdf format. Key Words: Hypothesis Testing, ANOVA, Descriptive Statistics, Regression, Correlation, Nonparametric Tests, Probability Distributions, Counting, Central Limit Theorem.
• ### **National Library of Virtual Manipulatives: Scatterplot

This Java Applet of a scatterplot allows you to enter data, move data points, define the range of values, and view graph value information.