When you are ready to collect some data, select the number of trials and click on the "Start Test" button below. After a brief pause, a coloured circle will appear. You should click as close to the centre of the circle as you can, and as quickly as you can. Each time you click another circle will appear elsewhere in the window.
Select guide if you want the centre of each circle to be marked.
Your results will be displayed as follows:
The colour of the circle, as red or green
The distance your click was from the centre of the circle, measured in points on the screen.
The time it took to click, measured in seconds.
The data is formatted for easy pasting into most statistics packages. Here are some problems that you can investigate:
There are many interesting problems that can be asked using data generated by this applet. Make up your own problem, gather the data, and then answer the question.
(This applet was inspired by an exercise in ActivStats.)