Stats M. 3 Flashcards
probability is a number between…
0 and 1
probability can be expressed as…
fraction, decimal, or percentage
subjective probability
based on personal opinion
ex. there is a 30% chance that I will attend the next Miami hockey game
theoretical probability
based on formulas
ex. the probability of getting head when flipping a fair coin is 50% since there are two possible outcomes and both are equally likely
experimental probability
based on the results of a random experiment
ex. flip a coin 10 times and use the proportion of times you obtain heads to estimate the probability of getting heads
Law of large numbers
if we repeat an experiment a large # of times the results that we see experimentally should be closer and closer to what we would expect to see theoretically
sample space
collection of all possible outcomes
-tree diagrams
-venn diagrams
event
a subset of the sample space, a collection outcomes
-a single outcome (getting head on a coin flip)
-several outcomes (rolling an even number on a die)
-the entire sample space
-no outcome at all
complement
the subset of all outcomes within the sample space that are NOT in the event A of interest
intersection
(A and B) The event containing all of the elements that are common to both A and B
union
(A or B) The event containing all of the elements that belong to either A only, B only, or both A and B
mutually exclusive
events that have no outcomes in common
-cannot happen at the same time
Complements P(A^c)=
1-P(A)
Unions P(A or B)=
P(A)+P(B)-P(A and B)
Correct postive
test result indicates that the condition is present, and it is
