Unit 4 Test Flashcards
General Additon Rule
P(AUB) = P(A) U P(B) - P(AnB)
Or rule
Disjoint Events
Multiplication Rule
P(A) x P(BIA)
And rule
Independent Events
How to make a Venn Diagram for probabilites involving “and” and “or”
And: They over lap and have a middle for and
Or: The two circles will never cross
Law of Large Numbers
Law of averages does not exist
Complement Rule
At Least
P(BIA)=P(AnB)/P(B)
Find the opposite of what you are looking for a subract it from 1
Geometric Models
number until next sucess
Binomial Models
How many successes in a certain number of trials
Find conditional probabiliitites
Use the tree and multiplication rule
Events are disjoint
AKA Mutually Exclusive
2 events cannot happen at the same time
How do you determine if events are independent
P(AIB)=P(A)
E(x)
Mulitply x by probability to find the probability of it
How do you find expected values?
Sum of XP(x)
How do you find Variance and what is it?
expected value of SD
(x-average)^2 x P + …
What does P(BIA) mean?`
The probability of B occuring if A has already happened
Discrete
you know all the outcomes
Continuous
A range or limitless outcomes
How do you find the SD with VARS?
Square root the VAR
How do you add SDs?
SD^2 + SD^2
Benoulli Trials
Only 2 outcomes, must sample less than 10%, probablity is independent of each other
How do you find the mean and SD for geometric models?
Mean: 1/p
SD: squareroot failure/p^2
How do you find mean and SD in bionomial models?
mean: np
SD: square root npq
What does q mean?
Probability of failures
When do you use pdf?
for an individual answer
When do you use cdf?
Adding the numbers
How do you do normal model?
Find the z score ( x-mean/ SD) and plug it into INVNORM (use binomial SD and mean)
