The Rice Virtual Lab in Statistics
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In this demonstration you specify the number of events (N) and the probability of success for any one event (p) and push the "OK" button. The initial graph shows the probability distribution associated with flipping a fair coin 12 times defining a head as a success. The vertical lines represent the probabilites of obtaining each of the 13 possible outcomes (0-12 heads). As you would expect, the most likely outcome is 6 heads. This probability distribution is called the binomial distribution.

The blue distribution represents the normal approximation to the binomial distribution. It is a very good approximation in this case. The higher the value of N and the closer p is to .5, the better the approximation will be.

Vary N and p and investigate their effects on the sampling distribution and the normal approximation to it.

visits since 11/6/96.