Resource Library

This Department of Energy website provides weekly average gasoline prices for several regions, states and cities. The averages are produced from a weekly survey of around 800 retail gasoline stations. The site includes information on data collection methods, survey methodology and historical data.

An independent, nonpartisan resource on trends in American public opinion. Gives examples of recent polls, margins of error, questions asked, and sample sizes.

A short discussion of what outliers are and their helpfulness in analyzing data.

This page provides survey data on the sexual activity of male and female subjects and discusses choosing appropriate statistics to describe the data as well as reporting bias. It also links to a Chance article about the same study.

These are MIT's epidemiology database pages. Mortality data for the United States from 1890-1997, Japan from 1951-1994, and Massachusetts, New York, Pennsylvania, Illinois, California, Texas and Florida dating back to the late 1950's are provided.

This demonstration allows you to view the binomial distribution and the normal approximation to it as a function of the probability of a success on a given trial and the number of trials. It can be used to compute binomial probabilities and normal approximations of those probabilities.

This free online video program "shows how to improve the accuracy of a survey by using stratified random sampling and how to avoid sampling errors such as bias. While surveys are becoming increasingly important tools in shaping public policy, a 1936 Gallup poll provides a striking illustration of the perils of undercoverage."

This online, interactive lesson on random samples provides examples, exercises, and applets concerning sample mean, law of large numbers, sample variance, partial sums, central limit theorem, special properties of normal samples, order statistics, and sample covariance and correlation.

This Java applet tutorial prompts the user to input the components of a hypothesis test for the mean. Hints are provided whenever the user enters an incorrect value. Once the steps are completed and the user has chosen the correct conclusion for accepting or rejecting the null hypothesis, a statement summarizing the conclusion is displayed. The applet is supported by an explanation of the steps in hypothesis testing and a description of one-tailed and two-tailed tests.

This pdf file gives definitions for average, standard deviation, and relative standard deviation, and works through a short problem as an example.