Conditional probabilities are used to measure the
impact of a cause on your behavior. This lecture introduces you to the
calculation of conditional probability.
 Define probability
 Test for conditional independence among various causes of your behavior
 Make a causal model of what leads to your behavior
 Measure the impact of a cause on your behavior using probability
statements
 Read introduction to probability concepts
More►
 Lecture on measuring impact of a cause:
Advanced learners like you, often need different ways of understanding a topic. Reading is just one way of understanding. Another way is through writing about what you have
read. The enclosed assessment is designed to get you to think more about the concepts taught in this session.
 What is the definition of probability?
 What is definition of conditional probability?
 How is the impact of a cause on the effect measured?
 What is meant by shrinking universe and how is this concept useful
in calculation of probabilities?

Every week ask a question
or comment on the lecture.
Comment► Ask►
 Calculate the probability of sleeping early, probability of
exercising and conditional probability of exercise after sleeping
late from the following Table:

Morning exercise

No morning exercise

Total 
Sleep early

0.60

0.20


Sleep late

0.05

0.15


Total 



Table5: Joint
probability of exercise and sleeping early


A person has hypothesized that there are two
causes of his exercise: sleeping early and having an
appointment with a buddy to exercise with, He has collected
two weeks of data presented in Table 6. Calculate which cause
is more likely to lead to exercise.
See it done►
SWF►
Day 
Sleeping
early 
Planning with buddy 
Exercise 
1 
Yes 
No 
No 
2 
Yes 
No 
No 
3 
Yes 
No 
No 
4 
No 
No 
No 
5 
No 
No 
No 
6 
No 
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 
12 
No 
Yes 
Yes 
Table 6: A Causal Diary of Exercise 
 Use of conditional probability in measuring impact of causes
PubMed►
 Analytical prevention of relapse
PubMed►
This page is part of the course on
Lifestyle Management This page was last edited on
10/22/11 by Farrokh Alemi, Ph.D ©Copyright protected.
