Flashcards in CH 5 Deck (13):
Rules of probabilities
1. P(E) must be greater than or equal to 0 and leas than or equal to 1. E = event
2. Sum must = 1
Typically less than 5% probability
Not so unsual
Probability of 1
Probability of 0
P(E) = ?
number of possible outcomes for E / number of total outcomes
E^c = ?
the complement of E (all outcomes in the sample space S that are not outcomes in the event E.
General addition rule to find probability
P(E or F) = P(E) + P(F) - P(E and F)
Multiplication rule (when E and F are independent)
P(E and F) = P(E) x P(F)
Complement rule = at least one
P(E^c) = 1 - P(E)
Example: P(at least 1 nonfiction) = 1 - P(all 4 fiction)
Notation P(F| E) = ?
Probability that the event F occurs, given that the event E has occurred.
Conditional probability rule
P(F| E) = P(E and F) / P(E)