CALIFORNIA STATE UNIVERSITY, HAYWARD
STATISTICS DEPARTMENT

Statistics 1000 Elements of Probability and Statistics

MINI-PROJECT 2a

Flip a coin 100 times. Stop after each time you have accumulated 10 more flips (i.e. after 10 flips, 20 flips, 30 flips, etc.) and compute the proportion of heads using all of the flips up to that point. Plot that proportion versus the number of flips. Comment on how the plot relates to the relative-frequency interpretation of probability.

To help organize you project consider making as table such as this.

Flip # 10 20 30 40 50 60 70 80 90 100

# of H 4 6 2 … ??

cumulative # of H 4 10 12 … ??

relative frequency 4/10 10/20 12/30 ??/100

0.40 0.50 0.40

To plot the data in Minitab, type the proportions at the bottom of the table into c1. Then click Graph > Time Series Plot. Click c1 and OK.