The ‘PayOff’ table below shows the times taken to travel from one point to another in a particular city. It is possible to make this journey on either a motorway ‘M’ or a high class ordinary road ‘A’. Journey times are in either case affected by weather conditions and the driver of a coach chooses to take the high class road in preference to the motorway when the latter is jammed with traffic. The probability that the motorway will be jammed has been assessed as 0.15.
| DECISION ALTERNATIVES | STATES OF NATURE |
|
| M CLEAR S1
| M JAMMED S2
| A | d1
| 30 | 30 | M | d2
| 25 | 45 |
For the weather conditions the probabilities for clear (C), overcast (O), and rain (R) are as follows:
P(C êS1) = 0.8 | P(O êS1) = 0.2 | P(R êS1) = 0.0 | P(C êS2) = 0.1 | P(O êS2) = 0.3 | P(R êS2) = 0.6 |
Calculate the probability of each weather condition and the conditional probability that the motorway M will be clear S1, or jammed S2, given each weather condition.
Calculate the probability of each weather condition and the conditional probability that the motorway M will be clear S1, or jammed S2, given each weather condition.
晴天的概率是不是1/3? P (S1/ C)倒是可以求出来，问题是题目有些糊涂 | 
