+1 862 207 3288 Purchase Behavior for Big-Screen Televisions
Planned To Purchase
Actually Purchased
Yes
No
Total
Yes
200
50
250
No
100
650
750
Total
300
700
1000
In the above table, households are classified according to whether they planned to purchase and whether they actually purchased big-screen
televisions. Draw the Decision Tree for this example.
Purchase Behavior Regarding Plasma Screen Televisions and DVR.
Purchased Plasma Screen
Purchased DVR
Yes
No
Total
Plasma Screen
38
42
80
Not Plasma Screen
70
150
220
Total
108
192
300
Using the cross-classified data above, construct the decision tree. Use your Decision Tree to find the probability that a household
purchased a DVR, given that the household purchased a plasma-screen television.
(Note: the probability formulas for question 2 are listed below)
The probability of A given B is equal to the probability of A and B divided by the probability of B.
P(A/B) = P(A and B)/P(B)
The probability of B given A is equal to the probability of A and B divided by the probability of A.
P(B/A) = P(A and B)/P(A)
Where:
P(A and B) = joint probability of A and B
P(A) = marginal probability of A
P(B) = marginal probability of B
