Sampling Techniques Flashcards
What is opportunity sampling?
Taking the sample from people available at the time the study is carried out and who fit the criteria you are looking for.
What are the advantages of opportunity sampling?
Suitable for studying generic processes e.g. memory.
Sometimes the only option - when on a field experiment.
Less time consuming - you just approach people who fit your criteria.
What are the disadvantages of opportunity sampling?
Can lead to a biased sample e.g. people from similar backgrounds.
People may not wish to participate.
What is random sampling?
Everyone in the population has an equal chance of being chosen. This involves identifying everyone in the target population and then selecting the number of participants needed.
What are the advantages of random sampling?
One of the most unbiased selection.
Efficient when using a computer.
What are the disadvantages of random sampling?
Compiling list is time consuming.
May become self selecting.
What is self selected sampling?
Consists of participants becoming part of a study because they volunteered when asked or in response of and advert.
What are the advantages of self selected sampling?
Wide reaching.
More ethical - volunteers have chosen to participate.
Researchers can specify characteristics.
Easier to manage participants.
What are the disadvantages of self selected sampling?
Not representative of non-volunteers / target population.
Participants are more willing / obedient - may change their behaviour.
What is stratified sampling?
Classifying the population into categories and then choosing a sample which consists of participants from each category in the same proportion as they are in the population.
What are the advantages of stratified sampling?
Researcher controls the categories.
Eliminates the effect of the variable on which the sample is stratified.
What are the disadvantages of stratified sampling?
Very time consuming - have to know the categories and proportions of the target population, etc.
Hard to complete a concise list.
