This applet simulates sampling from a population with a mean of 50 and a standard deviation of 10. For each sample, the 95% and 99% confidence intervals on the mean are computed based on the sample mean and sample...

This applet allows you to explore the validity of confidence intervals on a proportion with various values for sample size (N) and population proportion (Pi). After you specify N, Pi, the level of confidence, and the...

This material is a detailed exercise for students in introductory statistics. Students are asked to collect a random sample of data from a real estate website; conduct descriptive statistics (including confidence...

This website, created by Richard Lowry of Vassar College, calculates the z-ratio and associated one-tail and two-tail probabilities for the difference between two independent proportions. The page is very flexible in...

This page, created by Richard Lowry of Vassar College, calculates the standard error of a sampling distribution of sample means when users input the mean and standard deviation of the population and the sample size. This...