Explanation:
At the beginning of the course, we
discuss the relative frequency approach to defining
probability. If a random experiment is repeated N times, and
event A occurs N(A) times, then the relative frequency
of event A is given by r(A)=N(A)/N . The probability of A, denoted
as Pr(A), is defined as the limit of r(A) as
N goes to infinity.
To experiment with this applet, first set the number of trials (default is 10) and the probability of heads (default is p=0.5 for a fair coin). You can do this by sliding the bars or by entering the numbers from the key pad (be sure to confirm your entries by hitting the return key). Click on the Start button and the animation will start. An internal random number generator determines whether the next flip is a head or a tail based on a chance mechanism and the chosen p. Every time a coin is flipped, both N and N(A) registers are updated and the resulting r(A) calculated. The top right window displays the running r(A) curve as a function of N. It can be seen that as N increases, r(A) stabilizes and approaches the value of p that is pre-selected. The program can be terminated or expedited at any time by clicking the Stop button.
Experiment it yourself!
Click here to run the experiment using
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