STAT7055
WORKSHOP SLIDES
Week 3
Week 3
STAT7055 - Workshop Slides 2 / 7
Week 3
Week 3 Announcements
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Zoom).
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STAT7055 - Workshop Slides 3 / 7
Week 3
Topic 2 Review
◮ Useful approach for probability problems.
1. Read through the problem carefully and define some
appropriate events.
2. Write down the information given in the problem
(i.e., the probabilities) in terms of the events you
have defined.
3. Write down the probability you want to find.
4. Determine which probability rule(s) will be most
useful to calculate that probability.
STAT7055 - Workshop Slides 4 / 7
Week 3
Week 3 Workshop
◮ Adrian loves cats and likes to help out the local
animal shelter by adopting kittens that are currently
living at the shelter. Anytime Adrian adopts a
kitten, there is an equal probability that it is male or
female and the sex of the kitten is independent from
adoption to adoption. Adrian currently has two
kittens that were adopted from the shelter. Adrian’s
friend asks him whether he has a male kitten, to
which Adrian answers that he does. What is the
probability that the other kitten is female?
STAT7055 - Workshop Slides 5 / 7
Week 3
Week 3 Workshop
◮ Monty Hall problem. You are on a game show
where you are given the choice of three suitcases,
only one of which contains a million dollars. You
choose a suitcase, but before you open it, the game
show host opens one of the other two suitcases and
shows you that it’s empty (we can assume the host
knows which suitcase contains the million dollars).
You are now given a choice to either stay with the
suitcase you originally chose, or to switch to the
other unopened suitcase. What should you do?
STAT7055 - Workshop Slides 6 / 7
Week 3
Week 3 Workshop
◮ What happens if you were instead given a choice of
four suitcases, only one of which contains a million
dollars? Back in the first situation with three
suitcases, what happens if, after you choose a
suitcase, this time the host chooses one of the other
two suitcases randomly and shows you that it’s
empty?
STAT7055 - Workshop Slides 7 / 7