Probability Flashcards
1
Q
in the long run, what is the relative frequency of an event equal to?
A
probability of its occurrence
2
Q
definition: union
A
either A or B, or both A and B
3
Q
definition: intersection
A
both A and B
4
Q
definition: complement
A
complement of A is the event “not A”
5
Q
what is the additive law of probability?
A
- probability that two events will occur is equal to the sum of the probabilities of the individual events
- must be mutually exclusive events (or else you need to subtract the overlapping probability)
6
Q
what is the general rule of multiplication of probability?
A
- if A has already occurred, the probability of A and B occurring = probability of A x B given A
- events must be dependent upon one another
7
Q
what rule is applied for the joint probability of independent events?
A
special rule of multiplication
8
Q
when is Bayes’ theorem used?
A
when events are not independent - to derive more precise probability
