AP Statistics Unit 7

sampling distribution

collection of sample statistics (results from many samples of the same size

Higher n = …

less variability

population

all subjects under study EX: ALL REESE’S PIECES

sample

subset/subgroup of the population, relative to sample size
EX: 25 REESE’S PIECES

parameter of interest

characteristics of the population we want to know

p = proportion of orange

sample statistic

characteristic of sample

How to generate a random sample

Randbin (input features of data set)

Graphs for sampling distribution

y axis= # of samples (INCLUDE N=SAMPLE SIZE)

x axis= proportion of (what we are looking for)

up

true proportion/mean

standard deviation

-/pq/n

1:SRS

unbiased sampling method: representative of population

Independence of sample

If n is no more than 10% of the entire population, it is reasonable to assume independence of sampling (close enough to selection w/ replacement)

DONE SO WE CAN USE SD FORMULA

Normality/Sample size large enough

np >-10

nq>-10

the sample size is large enough to assume normality or normal distribution (at least 10 successes or failures for sound conclusions)

FOR STEPS,

write whether you have to assume or not BUT comment on it

To cut standard deviation by 1/3

9
STEPS:

mult 1/3

consider sqrt

1/9

consider ^-1

9

OR"

put in sqrt with a square attached

what calc function to use

normcdf