SAMPLING?

Learning Research methodology can be very confusing.  A chapter on a simple subject like sampling can challenge your mind because there are just so many types of it.  So, today I would like to share a little bit of knowledge on this matter.

Population   -   The large group to which one hopes to apply the                                results. 

Sample        -   The group on which information is obtained.

Target population - actual population to which a researcher would really like to generalize is rarely available.

Accessible population - The population to which a researcher is is able to generalize.

Simple random sample - each and every member of the population has an equal and independent chance of being selected.

Nonrandom sample - a sample in which a complete list of respondents is not available, so the respondents are selected based on other characteristics.

Stratified random sampling - a population sample that requires the population to be divided into smaller group, called strata.

Cluster random sampling - researcher divides the population into separate group, called clusters.  Then, a simple random sample of clusters is selected from the population

Two stage random sampling - combination of cluster random sampling with individual random sampling.