Sampling Methods and Design Flashcards

What is the purpose of random sampling?

Answer: To ensure every member of the population has an equal chance of being selected

Random sampling gives each population member an equal selection probability, reducing selection bias and supporting generalizability.

What is stratified sampling?

Answer: Dividing the population into subgroups and sampling from each proportionally

Stratified sampling ensures representation of important subgroups by dividing the population into strata and sampling from each.

What is sampling bias?

Answer: A systematic error that results in a non-representative sample

Sampling bias occurs when the selection method systematically favors certain members over others, producing unrepresentative results.

What determines the minimum sample size needed for a study?

Answer: Desired confidence level, margin of error, and population variability

Sample size calculations consider the desired precision, confidence level, population variability, and effect size.

What is cluster sampling?

Answer: Dividing the population into clusters, then randomly selecting entire clusters to study

Cluster sampling randomly selects groups (clusters) rather than individuals, then studies all members within selected clusters.

Why is non-response bias a concern in survey research?

Answer: Non-respondents may differ systematically from respondents, skewing results

Non-response bias occurs when people who do not respond differ from those who do, potentially distorting findings.