Section 6.3.1 Probability Models

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Section 6.3.1Probability Models

• AP Statistics
• toddfadoir.com/apstats

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Venn Diagrams Disjoint Events
S
A
B
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Venn Diagrams Disjoint Events
S
A
B
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Venn Diagrams Non-disjoint Events
S
B
A
A and B
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Venn Diagrams Non-disjoint Events
S
B
A
A and B
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Example

• Deborah and Matthew are awaiting the decision
  about a promotion. Deborah guesses her
  probability of her getting a promotion at .7 and
  Matthews probability at .5.

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Example

• Deborah and Matthew are awaiting the decision
  about a promotion. Deborah guesses her
  probability of her getting a promotion at .7 and
  Matthews probability at .5.

D
M
.5
.7
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Example

• Since there is not enough information to do the
  problem, lets add information. Deborah thinks
  the probability of both getting promoted is .3

D
M
.5
.7
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Example

• Whats the probability of only Deborah getting
  promoted P(D-M)?
• P(M-D)?
• P(Dc)?
• P(Mc)?
• P(Dc and Mc)?

D
M
.5
.7
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Different Look
Matthew Matthew
Promoted Not Promoted Total
Deborah Promoted .3 .7
Deborah Not Promoted
Total .5
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Different Look
Matthew Matthew
Promoted Not Promoted Total
Deborah Promoted .3 .7
Deborah Not Promoted
Total .5 1.0
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Different Look
Matthew Matthew
Promoted Not Promoted Total
Deborah Promoted .3 .4 .7
Deborah Not Promoted .2
Total .5 1.0
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Different Look
Matthew Matthew
Promoted Not Promoted Total
Deborah Promoted .3 .4 .7
Deborah Not Promoted .2 .3
Total .5 .5 1.0
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Different Look
Matthew Matthew
Promoted Not Promoted Total
Deborah Promoted .3 .4 .7
Deborah Not Promoted .2 .1 .3
Total .5 .5 1.0
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Assignment

• Exercises 6.46-6.53, all