The worksheet below is designed to illustrate the importance of taking random samples. Over repeated random samples, the differences between samples will "average out" by piling up in an approximately normal distribution around the true mean or proportion.
There are twelve participants to choose from (names A, B, C, ... , L) and you will select six of them at random. You can change their Gender (M or F), their Heights, or their Ages in the spreadsheet.
You can enter the number of random samples you wish to take in the input box so you can see what happens over repeated samples. A dot plot is created for the mean height or mean age of each sample, or the proportion of females in each sample. Use the checkboxes to select which dot plot to view. The red vertical line in each dot plot shows the true population mean or proportion.
