标题: Joint Probability Question (from Schweser) [打印本页] 作者: hanvinh 时间: 2011-7-13 16:42 标题: Joint Probability Question (from Schweser)
Schweser says the answer is A, but I think it's C. Isn't a joint probably a situation of "A" given "B", thus both have to occur?
Which of the following is a joint probability? The probability that a:
A)stock pays a dividend and splits next year.
B)company merges with another firm next year.
C)stock increases in value after an increase in interest rates has occurred.
Your answer: C was incorrect. The correct answer was A) stock pays a dividend and splits next year. A joint probability applies to two events that both must occur.作者: ftwcfa 时间: 2011-7-13 16:42
Yes, it can be quite confusing.
Maybe easier way to retain this is thru their symbols.
Joint Probability is: P(AB)
Probability of A given B is: P(A|B)
And relationship between the two is: P(AB) = P(A|B) * P(B)
Hope this helps.作者: jim8z3 时间: 2011-7-13 16:42
Keyword for joint probability is "and" while keywords for conditional are "given that", "after" etc.作者: ramdabom 时间: 2011-7-13 16:42
P(A|B) means B has happened, A may or may NOT happen. P(AB) means both happen作者: johnnyBuz 时间: 2011-7-13 16:42
narayanan87 Wrote:
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> P(A|B) means B has happened, A may or may NOT
> happen. P(AB) means both happen
Correction.
Probability is just the chance of something occurring, the figure by itself tells us nothing about whether the event has occurred.
