Sampling

sampling

the process of selecting units from the population of interest

population

the group you want to generalise to and the group you sample from in a study

generalising

the process of making an inference that the results observed in a sample would hold in the population of interest

theoretical population

a group which, ideally, you would like to sample from and generalise to

accessible population

a group that reflects the theoretical population of interest and that you can get access to when sampling

sampling frame

the list from which you draw your sample

sample

the actual units you select to participate in your study

simple random sampling

a method of sampling that involves drawing a sample from a population so that every possible sample has an equal probability of being selected

stratified random sampling

a method of sampling that involves dividing your population into homogeneous subgroups and then taking a simple random sample in each subgroup

systematic random sampling

a sampling method where you determine randomly where you want to start selecting in the sampling frame and then follow a rule to select every x the element in the sampling frame list

cluster (area) random sampling

a sampling method that involves dividing the population into groups called clusters, randomly selecting clusters, and then sampling each element in the selected clusters

multistage sampling

the combining of several sampling techniques

sampling distribution

the theoretical distribution of an infinite number of samples of the population of interest in your study

normal curve

a common type of distribution where the values of a variable have a bell-shaped histogram or frequency distribution

census study

doesn’t pick a sample, tries to study the whole population

respondent-driven sampling

A nonprobability sampling method that combines chain-referral or snowball sampling, with a statistical weighting system that helps com pensate for the fact that the sample was not drawn randomly

response

a specific measurement value that a sampling unit supplies

statistic

a value that is estimated from data

population parameter

the mean or average you would obtain if you were able to sample the entire population

standard deviation

an indicator of the variability of a set of scores in a sample around the mean of that sample

standard error

the spread of the averages around the average of averages in a sampling distribution

sampling error

error in measurement associated with sampling