Systematic random sampling Research population Sampling frame Sample

Systematic random sampling Research population Sampling frame Sample those who can be included in the research A list of names which make up a research population The smaller, sub-group who we actually research A representative sample It is a cross section of the population they are interested in A representative sample will give you generalisability Every nth person is chosen from a sampling frame. Stratified random sampling A random sample is taken from particular social categories, e. g. age, gender, race, etc. , which make up the population being studied. Quota is mainly used by market researchers in the street. For example, they may be under instructions to stop and interview a quota of housewives aged between 25 and 40 years of age Purposive Participants are selected according to the needs of the study (hence the alternate name, deliberate sampling); applicants who do not meet the profile are rejected. Opportunity It consists of taking the sample from people who are available at the time the study is carried out and fit the criteria your are looking for. Snowball is mainly used in areas in which it is difficult to find a sample because behaviour is seen as deviant by society, e. g. a researcher interested in heroin addiction may find an addict willing to introduce him or her to other addicts. Volunteer A voluntary sample is made up of people who self -select into the survey.