# Measurements Properties & Issues

• ### Getting What You Pay For: The Debate Over Equity in Public School Expenditures

This article addresses a dataset on public school expenditures and SAT performance. Key Words: Multiple regression; Omitted variable bias; Partial correlation; Scatterplot.
• ### Dataset Example: Televisions, Physicians, and Life Expectancy

This article describes a dataset on life expectancies, densities of people per television set, and densities of people per physician in various countries of the world. The example addresses correlation versus causation and data transformations. Key Word: Prediction.
• ### Can a difference be important if it is not significant?

This short article discusses the difference between "important" and "statistically significant." The data used come from a study comparing male faculty salaries to female faculty salaries.
• ### What are outliers in the data?

This excerpt from Engineering Statistics Handbook gives a definition for and examples of outliers. A sub-page also discusses Grubbs' Test for Outliers
• ### Box Model

This virtual applet simulates randomly drawing numbers from a box. You can choose which numbers you would like to choose from and the number of draws. The applet has the option to show theoretical probability and displays the results in histogram form.
• ### Statgraphics Software Program

As taken from the web site: "STATGRAPHICS Centurion is designed for anyone who wishes to do serious data analysis without investing weeks learning how to use a statistical package. It contains over 150 statistical procedures, covering everything from summary statistics to design of experiments. Yet you don't need to be a statistician to use the program. Everything is completely menu-driven, and there are tools such as the StatWizard and StatAdvisor to help you use the program most effectively." This program is available in three editions:Standard, Professional, and Enterprise.

• ### Religious Fundamentalism and Optimism

This example is designed to test whether religiosity is correlated with optimism. The page describes the study, has a link to the data set, and describes the method of analysis. Analysis includes ANOVA and regression.
• ### One-way Anova of PTSD Data

This page was written as instructions for a SAS lab assignment, but the example can be used with other programs. The study compares three treatments for rape victims against each other and a control group to see which treatment is most effective at reducing Post Traumatic Stress Disorder symptoms.