Set the population size, then set the sample size n and click the SAMPLE button to take a sample. Click RESET to move all the balls back from the Sample area into the "Population hopper".
Click the "Quiz Me" button to complete the activity.
A sample selected in such a way that every sample of the desired size is equally likely to be chosen is called a simple random sample (SRS). This applet lets you randomly sample a population of lotto balls, where the population size can be set anywhere between 1 and 144.
Set the size of your "population" of lotto balls in the applet to 10. What is the mean value of this population?
If you choose three random samples of this population, what would you expect the average sample mean to be?
Take three random samples of 3 balls each from your population of 10 balls. After taking each sample, enter the sample's mean below (accurate to one decimal place):
Sample 1:
Sample 2:
Sample 3:
Now calculate the average sample mean of your three samples. Was this average equal to the expected value (5.5)? If not, does this surprise you?