Tom Trollen's
GBS221 Links

Rice Virtual Lab in Statistics:

Descriptive Statistics  A Java applet which shows histogram of a changeable data set and calculates several descriptive statistics (mean, median, standard deviation, skew, and deviations worksheet).

Normal Approximation to the Binomial Distribution  A Java applet which shows how well the Normal Distribution approximates a specified Binomial Distribution.

Regression by Eye A Java applet which shows a scatter plot and allows you to eyeball the location of the least squares regression equation and the correlation coefficieint.

Guessing Correlations A Java applet which shows scatter plots that you match to correlation coefficients.

Least Squares A Java applet in which you can see how changes in the slope and/or intercept affect the sum of the squared residuals.

Gallup Organization Home page of one of the world's most respected polling organizations

How Polls are Conducted Discusses how Gallup conducts polls and the steps they take to obtain unbiased results

Public Agenda Online

Best Estimates: A Guide to Sample Size and Margin of Error

20 Questions Journalists Should Ask About Poll Results

ABC News: Poll Vault A year's worth of their polls

Washington Post

Poll Vault Lots of polls, searchable

Data Directory Links to many different organizations that publish polls on the web

International Communications Research Marketing research company; view results of polls they've conducted for their clients

Polling Report Online

Answers To Questions We Often Hear From the Public A nice summary of polling methodology

Download and install to read PDF files.

Center for Drug Evaluation and Research This branch of the US Food and Drug Administration is responsible for evaluating the safety and effectiveness of over-the-counter and prescription drugs.

US Census Bureau

Statistical Abstract Statistical information describing population, transportation, government, commerce (Adobe Acrobat files).