frame
the list used to assign numbers to the individuals in the population
sampling
using a smaller number of people to gather results that may be applied to a larger population of people
sampling without replacement
once an individual is selected, he/she is removed from the population and cannot be chosen again
random sampling
the process of using chance to select individuals from a population to be included in the sample
stratified sample
separating the population into nonoverlapping groups called strata and then obtains a simple random sample from each stratum.
the individuals within each stratum should be homogenous (similar) in some way
which sampling method does not require a frame?
systematic sampling
why are convenience samples not advised?
they are not probability samples; individuals who participate are often self-selected, so the results are not likely to be representative of the population
cluster sample
obtained by dividing the population into groups and selecting all individuals from within a random sample of the groups
stratified sample
obtained by dividing the population into homogeneous groups and randomly selecting individuals from each group