# One Numerical Variable

• ### Confidence Intervals

This site gives an explanation of, a definition for and an example of confidence intervals. It covers topics including inference about population mean and z and t critical values.
• ### Random Number Generator

As quoted on the site, "This website ... offers the possibility to download true random numbers generated using a quantum random number generator upon demand. Users can specify the length of the random number sequence and their upper boundary."

• ### Linear Regression Calculator

This is a virtual linear regression calculator. It allows students to enter data points, experiment with where the line of best fit might be, and then lets them see the correct line of best fit as well as the outliers. You can click through the introduction.
• ### Games of Chance

This online, interactive lesson on games of chance provides examples, exercises, and applets which include Poker, Poker dice, Chuck-a-Luck, Craps, Roulette, The Monty Hall Problem, lotteries, and Red and Black.
• ### Introduction to Statistics: Mean, Median, and Mode

The goal of this lesson is to introduce the concepts of mean, median and mode and to develop understanding and familiarity with these ideas. The activity lets students explore mean and median in an efficient way and the discussion helps them to formalize their knowledge of measures of center.
• ### Sampling Distribution Generator for Sample Mean Differences

This page generates a graph of the sampling distribution of the difference between two means and displays the probabilities associated with that distribution. Users enter the population standard deviation and the sample sizes, Na and Nb. The applet also calculates the standard error of the sample mean difference.

• ### Sampling Distribution Generator for r (Correlation Coefficient)

This page generates a graph of the sampling distribution of r, the Pearson correlation coefficient. Upon opening, the applet prompts for sample size greater than 6. The applet also displays the probabilities associated with the distribution.

• ### t-Distribution Generator

Generate a graphic and numerical display of the properties of the t-distribution for values of df between 4 and 200, inclusive.

• ### Poisson Sampling Distribution Generator

This page generates a Poisson distribution, as approximated by the Binomial. After clicking continue, users must enter the sample size (n>39) and probability of success (between 0.0 and 0.2, inclusive). A graph of the Poisson distribution with mean=np is shown as well as a table of the Poisson probabilities. Key Word: Poisson Calculator.

• ### Poisson Sampling Distribution Generator (with Specific Mean)

This page generates a histogram of a Poisson distribution and the associated table of probabilities. Upon opening the page, users will be prompted to enter the mean of the distribution (between 0.01 and 20.0, inclusive). Key Word: Poisson Calculator.