Ch6/7 probability normal distributions and z scores

in a normal distribution 50% of all data

fall above the mean median and mode and 50% fall below these measures

sampling error

the extent to which sample mean selected from the same population differ from one another. this difference which occurs by Chance, is measured by the standard error of the mean

the law of large numbers explained

the larger the sample size the smaller the standard error

the larger the standard deviation in the population

the larger the standard error

theoretical sampling

the order of selecting individual matters, and each individual selected is replaced before sampling again

experimental sampling

the order of selecting individuals does not matter, and each individual selected is not replaced before selecting against

the central limit theorem explained

this shape of a sampling distribution of sample means tends toward a normal distribution, regardless of the distribution in the population