Samples
A sample that is truly random
simple random sample
test for a population proportion
z test
np
mean
μ
true mean
curve with most values in the center
normal distribution
samples taken at a regular interval
systematic sample
test for a population mean
t test
square root of np(n-p)
standard deviation
lowercase sigma
true standard deviation
graph with mot values on the right
left skewed
a population is broken up into groups and each group is sampled from
stratified sample
test for homogeneity or independence
chi square test
statistic +/- (critical value)(standard error of statistic)
confidence interval
p
probablility
graph showing min, max, med, q1, q3
box and whisker plot
a population is broken into groups and whole groups are sampled
cluster sample
test to find difference in proportions
2 sample z test
(1-p)x-1p
geometric distribution
n
number
graph showing data points on a number line
dot plot
a sample of samples
sample distribution
test to find if the difference in mean is 0 or not
matched pairs t test
sum of (observed-expected)2/expected
chi square
z*
critical value
graph with 2 sets of numbers seperated by a line to make one number with a key
stem and leaf plot