Stats II Flashcards
What are the three different definitions of probability?
Classical
Frequentist
Subjectivist
What is the equation for probability?
p(x) = f(x) / sample space
What is a sample space?
All possible outcomes
Sum of frequencies = ?
Sample space
Over the long run, the relative frequency of an event is what?
The probability of its occurrence
What is a relative frequency?
Probability for each outcome in the distribution
What are the three operations?
Intersection
Union
Complement
What is the additive law?
probability of mutually exclusive events (disjoint) is the sum of their probabilities
When is the additive law not applicable?
When the two events in questions are not mutually exclusive
What is the general rule of addition?
need to subtract the intersection of two events
What is the special rule of multiplication?
Events are independent, then multiply their probabilities
or = independent or dependent?
Independent
Sum of probabilities of ALL disjoint events = ?
1
What is the prior probability?
The probability that is known prior to the calculation of Bayes theorem
What is posterior probability?
The probability that is calculated in Bayes theorem
What is a collection of one or more outcomes of an experiment?
An event
A compound event is what?
Event that has multiple operations within it
What are mutually exclusive events/disjoint?
When they cannot occur simultaneously
What is the additive law?
The probability of two disjoint events occurring is the sum of their probabilities
What is the general rule of addition?
If two events A and B are not mutually exclusive, then the probability that both occur is the sum of their probabilities, minus in the intersection of the two
What is the general rule of multiplication?
If we know that an event A has already occurred, the probability that two events A ad B will both occur is equal to the probability of A, times the probability of B, given A.
What is the special rule of multiplication?
If A and B are independent events, then the probability that both occur is the product of their probabilities