gowni nwm kys Flashcards
systematic sampling
Individuals are selected at regular intervals from the sampling frame. The intervals are chosen to ensure an adequate sample size. so sampling every nth person
so every nth person
simple random sampling
In this case each individual is chosen entirely by chance and each member of the population has an equal chance, or probability, of being selected. so just random people
stratified sampling
In this method, the population is first divided into subgroups (or strata) who all share a similar characteristic called strata
clustered sampling
subgroups of the population are used instead of individuals
convenience sampling
the easiest method of sampling, because participants are selected based on availability and willingness to take part
quota samping
this method of sampling is often used by market researchers. Interviewers are given a quota of subjects of a specified type to attempt to recruit. For example, an interviewer might be told to go out and select 20 adult men, 20 adult women, 10 teenage girls and 10 teenage boys so that they could interview them about their television viewing. Ideally the quotas chosen would proportionally represent the characteristics of the underlying population.
purposive sampling
relies on the selection of the researcher when choosing who to ask to participate. Researchers may implicitly thus choose a “representative” sample to suit their needs, or specifically approach individuals with certain characteristics
snowball sampling
this method is commonly used in social sciences when investigating hard-to-reach groups. Existing subjects are asked to nominate further subjects known to them, so the sample increases in size like a rolling snowball. For example, when carrying out a survey of risk behaviours amongst intravenous drug users, participants may be asked to nominate other users to be interviewed.
