EBD 601 Ch.6

cluster sampling

sampling in which intact groups, not individuals, are randomly selected

stratified sampling

a purposive process of selecting a sample: The population is subdivided into subgroups, and participants are strategically selected from each subgroup

sampling bias

systematic sampling error; two major sources of sampling bias are samples including only volunteers and sampling based on available groups

target population

the population to which the researcher would ideally like to generalize study results. Compare accesible population

simple random sampling

the process of selecting a sample in such a way that all individuals in the defined population have an equal & independent chance of selection for the sample

systematic sampling

sampling in which individuals are selected from a list by taking every Kth name, where K equals the number of individuals on the list (population size) divided by the number of subjects desired for the sample

purposive sampling

process of selecting a sample that is believed to be representative of a given population. Also called judgment sampling

nonprobability sampling

process of selecting a sample using a technique that does not permit the researcher to specify the probability, or chance, that each member of a population will be selected for the sample. Also called nonrandom sampling

accessible population

the population from which the researcher can realistically select subjects. Also called available population. Compare target population

conveinence sampling

process of including whoever happens to be available in a sample (volunteers). Also called accidental sampling or haphazard sampling

data saturation

a point in qualitative research at which so much data are collected that it is very unlikely that additional data will add new info

sampling error

expected, chance variation in variables that occurs when a sample is selected from a population

generalizable

applicability of research findings to settings & contexts different from the one in which they were obtained

cluster

any location that contains an intact group with similar characteristics (population members)

qualitative sampling

process of selecting a small number of individuals for a study in such a way that the selected individuals can help the researcher understand the phenomenon under investigationta

table of random numbers

a list of multidigit numbers, arranged in a table, that have been randomly generated by a computer to have no defined patterns or regularities; used in sampling. Also called table of random digits

probability sampling

process of selecting a sample using a sampling technique that permits the researcher to specify the probability, or chance, that each member of a defined population will be selected for the sample

quota sampling

process of selecting a sample based on required, exact number (quotas) of persons of varying characteristics