Quiz 2 Guideline Summer 2016
CH5 : Sampling Methods
What is sampling?
Sampling refers to “ the process of selecting units (e.g., people) from a population of interest” Or the process of taking a small group of people or things from a larger group and used to represent the larger group.
Understanding Population, sample, and individual case
Target Population – the entire group of people about whom researchers needs to obtain information.
Sample - the selected group of people chosen from the population for participation in research.
A case refers to a person or an object living in the area.
Why do we need sampling?
Time and Money factors – sample provides researchers with needed information quickly and save money.
Large populations – a big size of population makes it difficult for researchers to collect all the data.
Help researchers to access to data – some populations are difficult to access . So, it is easier for researchers to access to a group of respondents rather than get access to whole population
Sampling Process
*** see how to calculate sample size by using formula and please remember formula
Sampling methods
Probability - is a sampling technique where the samples are gathered in a process that gives all the individuals in the population equal chances of being selected.
Random
Systematic
Stratified
Cluster
Non-probability - is a sampling technique where the samples are gathered in a process that does not give all the individuals in the population equal chances of being selected
Quota
Snowball
Purposive sampling
Convenience
*****Essay question