P-value Applet Instructions

The applet displays a coin with unknown probability of heads. Your job is to determine whether the coin is fair (i.e. the probability of heads is equal to the probability of heads).

Use the buttons to toss the coin once or 100 times. The outcomes are displayed in the box to the right of the coin. The coin will show the result of the most recent toss.

Under the box, the display indicates the number of times the coin has been tossed, the number of heads observed, and the number of heads that we would expect to observe if the coin is fair.

Lower down, the display indicates the distance between the observed number of heads and the number that would be expected if the coin were fair. Below this, the applet displays the probability of getting results like these if the coin is fair. This probability is computed from the binomial distribution.