Now move your mouse slowly from left to right over the rectangle.
    Select the distribution that you want to sample from.
This is a simulation of randomly selecting thousands of samples from a chosen distribution. The purpose of this simulation is to explore the Central Limit Theorem.  You will learn how the population mean and standard deviation are related to the mean and standard deviation of the sampling distribution. 

First you will be asked to choose from a Uniform, Skewed Left or Right, Normal, or your own made up distribution.  The distribution is set to range from 0 to 400.  To choose your own distribution, select "User".  Then move your mouse to the far left of the distribution box and slowly move it to the far right.  When you have arrived at the far right, the distribution will be set.  Then you will be asked for the sample size.  For example, if you click on "n = 25" the computer will select thousands of samples with sample size 25.  It will compute the means of each of the thousands of samples and draw a histogram of these means.  The computer will show you the mean and standard deviation of the original distribution and the approximate mean and standard deviation of the the sampling distribution.  Then click on the "to scale" button to set the y-axis scale for the population distribution to be the same as the y-axis scale for the sampling distribution. 

Compare and contrast the means and standard deviations.  Also, what do you notice about the sampling distribution?  This demonstrates the Central Limit Theorem.

Click here for more information about the Central Limit Theorem.
Questions, Comments, Suggestions:  email Larry Green (DrLarryGreen@gmail.com) at Lake Tahoe Community College