samples and populations 1 Flashcards
what is the range of probability
0.00 - 1.00
what is an analytic view in probability
the normal way of just once then doing maths and finding the probability
what is a frequentist view of probability
sampling with replacement in large number of draws and then find about 705` result in X
If an event can occur in A ways and can fail to occur in B ways and all outcomes are equally likely then what is the formula
p(event A) = A/(A+B)
p(event doesn’t occur) = B/(A+B)
what does mutually exclusive mean
Occurrence of one event precludes the occurrence of the another event
aka you cant be a part more than one year group
what does independent event mean
Occurrence of one event has no effect on the probability of the occurrence of another event
e.g. die rolling
what rule does mutual exclusion employ
additive rule
OR
what is the additive rule
the probability of occurrence of one event or another is equal to the sum of their separate probabilities
OR
what rule do independent events employ
multiplicative rule
AND
what is the multiplicative rule
The probability of the joint occurrence of two or more independent events is the product of their individual probabilities
AND
What is the AND vs OR probability rule
if AND is used then to work out prob of 2 events happening you MULTIPLY
if OR is used then to work out prob of either 2 happening you ADD probs
additive rule: what happens when p(A or B) are not mutually exclusive
Probability of the occurrence of some particular events is included twice, so one must subtract it from the total probability
p(A or B) = p(A) + p(B) – p(A and B)
Multiplicative rule: What happens if p(A and B) are not independent?
there’s a conditional probability: Probability of one event given the occurrence of another p(B|A)
e.g. without replacement= dependent events
define combinations; what do you use for them
Number of ways to arrange a subset of objects; computational formula
what is N in the computational formula
number of events
