Unit 7 Flashcards
1
Q
Which symbols do you use for Statistics (Samples) *Note the S!
A
- x bar: mean
- s: standard deviation
- s^2: variance
- p hat: proportion
2
Q
Which symbols do you use for Parameters (Populations) *Note the P!
A
- u: mean
- o: standard deviation
- o2: variance
- p: proportion
3
Q
What do you do when a question gives you variance?
A
Square it to turn it into s.d.
4
Q
If you draw random samples of size n from a population with a mean of u and an s.d. of o, then:
- The “mean of x bar” =
- The “s.d. of x bar” =
A
- u
- o/square root of n
5
Q
What is the central limit theorem?
A
When n is large, the sampling distribution of the sample mean is approximately normal.
(Used when n > 30)
