sampling Flashcards
(30 cards)
What is a population in research?
The large group of individuals a researcher is interested in studying.
Why do researchers use samples instead of entire populations?
Due to practical and economic reasons.
What is a sample?
A smaller group selected from the population for investigation.
What makes a good sample?
It should be representative of the target population.
Why is it difficult to get a truly representative sample?
Populations have diverse characteristics, making full representation hard.
What is a sampling technique?
A method used to produce a representative sample.
What is a random sample?
A sample where all members of the population have an equal chance of being selected.
How is a random sample selected?
List all members, assign numbers, and use a lottery method to pick (e.g. picking numbers out of a hat).
What is a systematic sample?
Every nth member of the population is selected.
What is a sampling frame?
A list of people in the target population used for selection.
What is a stratified sample?
A sample that reflects proportions of people in certain subgroups (strata).
How is a stratified sample created?
Identify strata, calculate proportions, and randomly select within strata.
What is an example of stratified sampling?
Dividing participants by cities and selecting in proportion to city size.
What is an opportunity sample?
A sample of people who are available and willing at the time of the study.
What is a volunteer sample?
Participants select themselves to be part of the sample.
What is a major issue with random sampling?
It is time-consuming and may still be unrepresentative.
Why is systematic sampling objective?
The system determines who is chosen, not the researcher.
What is a limitation of stratified sampling?
Strata may not reflect all ways that people differ.
Why is opportunity sampling convenient?
It is quick and doesn’t require a complete population list.
What is a downside of opportunity sampling?
It suffers from bias and poor generalizability.
What is researcher bias?
When a researcher selects participants based on preference.
What is volunteer bias?
Bias from participants who volunteer being different from the general population.
What motivates volunteer sample participants?
Curiosity and desire to help, possibly affecting results.
What method might be used to recruit a volunteer sample?
Adverts in newspapers or public notices.
