Measuring Impact of a Cause

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Measuring Impact of a Cause

• Farrokh Alemi Ph.D.

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Definition

• Ratio
• Prevalence of event
• Universe of possibilities

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Daily Probability of Exercise
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Daily Probability of Exercise
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Daily Probability of Exercise
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Probability Scale
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Axioms of Probability

• Is a positive number between 0 and 1
• The sum of the probabilities is 1
• Probability of two exclusive events is sum of the
  probability of each

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Venn Diagram
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Venn Diagram
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Probability of Exercise

• Days of exercise divided by total days
• Success divided by planned

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Combination of Events
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Combination of Events
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Probability of both events occurring together
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Probability of exercise in evening or morning
Amorning exercise Bevening exercise
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Impact of a Cause

• P(EffectCause)

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Impact of a Cause

• P(Effect Cause)
• P(B A)

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Impact of a Cause

• P(Effect Cause)
• P(B A)

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Impact of a Cause
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Impact of a Cause
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Numerical Example
 
  Morning exercise No morning exercise Total
Sleep early 15 12 27
Sleep late 2 1 3
Total 17 13 30
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Numerical Example
 
  Morning exercise No morning exercise Total
Sleep early 15 12 27


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Numerical Example
 
  Morning exercise Total
Sleep early 15 27


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Calculation from Diary data
Day Sleeping early Planning with buddy Exercise
1 Yes No No
2 Yes No No
3 Yes No No
4 No No Yes
5 No No No
6 Yes No No
7 No No No
8 Yes Yes Yes
9 Yes Yes Yes
10 Yes Yes Yes
11 Yes Yes Yes
12 Yes No Yes
13 No Yes Yes
14 No Yes Yes
15 No Yes Yes
16 No Yes Yes
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Calculation from Diary data
Day Sleeping early Planning with buddy Exercise
1 Yes No No
2 Yes No No
3 Yes No No
4 No No Yes
5 No No No
6 Yes No No
7 No No No
8 Yes Yes Yes
9 Yes Yes Yes
10 Yes Yes Yes
11 Yes Yes Yes
12 Yes No Yes
13 No Yes Yes
14 No Yes Yes
15 No Yes Yes
16 No Yes Yes
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Calculation from Diary data
Day Sleeping early Planning with buddy Exercise
1 Yes No No
2 Yes No No
3 Yes No No


6 Yes No No

8 Yes Yes Yes
9 Yes Yes Yes
10 Yes Yes Yes
11 Yes Yes Yes
12 Yes No Yes




9 days
26
Calculation from Diary data
Day Sleeping early Planning with buddy Exercise
1 Yes No No
2 Yes No No
3 Yes No No


6 Yes No No

8 Yes Yes Yes
9 Yes Yes Yes
10 Yes Yes Yes
11 Yes Yes Yes
12 Yes No Yes




9 days
5 days
27
Calculation from Diary data
Day Sleeping early Planning with buddy Exercise
1 Yes No No
2 Yes No No
3 Yes No No


6 Yes No No

8 Yes Yes Yes
9 Yes Yes Yes
10 Yes Yes Yes
11 Yes Yes Yes
12 Yes No Yes




9 days
5 days
28
Take Home Lesson

• Conditional Probability Measured Impact of a Cause