Research Methods : Sampling methods

Why do we need to take samples

Researchers can’t study everyone in the target population so they take a sample of them

What is opportunity sampling and e.g.

Selecting people that are available at the time. e.g. interviewing people on the street

What’s a pro and con of opportunity sampling

P= Quick ,convenient , saves time and money

C=Researcher bias —>unconsciously choses ppl who might prove ur hypothesis, sample won’t be representative of target audience

What is random sampling

Every member of a target population has an equal chance of being selected

What r the pros and cons of random sampling

P=no researcher bias

C=time consuming ,might be impossible that everyone has an = chance, might still get a bias sample

What is stratified sampling

When a target population is divided into distinct subgroups (stratas) based on shared characteristics (e.g age) and participants are then randomly selected from each subgroup to make up the sample

What are the pros and cons of stratified sampling

P= avoids researcher bias and representative sample obtained

C=working out the stratas and sample is time consuming

What is systematic sampling

When every nth member of the target population is selected till the sample size is made up

What are the pros and cons of systematic sampling

P= avoids researcher bias, quite representative

C= need to locate a large list of ppl

What is volunteer sampling

When individuals have chosen to be involved in a study

What are the pros and cons of volunteer sampling

P=avoids researcher bias, quick and ethical (ppl have given their consent)

C= unrepresentative (only the ppl who see the ad have a chance to be in the sample)