Collecting Baseball CD-ROMs

1
Collecting Baseball CD-ROMs
Outcome Space

1. AL Central
2. AL West
3. AL East

1. NL East
2. NL Central
3. NL West

• How many boxes of cereal must I buy, on average,
  in order to collect all 6 CD-ROMs?
• Go to the Collector Problem Applet and choose
  Dice (6) from the pull-down menu.
• Perform 10 trials, keeping track of the Total
  Drawn for each trial.
• Compute the average drawn per trial.

2
Section 1.2 Interpretations

• Frequency Interpretation
• Probabilities are mathematical approximations to
  long-run relative frequencies.
• The probability of an event A is the relative
  frequency of A in a large number of trials.
• Example Probability of heads on the toss of a
  coin.
• Let Pn(H) be the proportion of times H occurs in
  n tosses.
• As n gets large, Pn(H) ? P(H)

3
Section 1.2 Interpretations

• Subjective Interpretation
• A probability statement expresses the opinion of
  an individual regarding how certain an event is
  to occur.
• It doesnt always make sense to think in the
  context of repeated trials.
• Probability of a particular patient surviving
  breast cancer.
• Probability of a particular stock going up in
  value next year.
• Probability that Lydia (my daughter) will be a
  mathematician.
• Weather forecasting!