Sampling Methods Flashcards
What is the difference between simple random sampling and systematic sampling?
Simple random sampling involves selecting subjects purely by chance, while systematic sampling selects every nth item in a list.
How do you perform stratified sampling?
Stratified sampling involves dividing the population into strata and sampling from each stratum proportionally or equally.
What is cluster sampling, and when is it used?
Cluster sampling groups subjects into clusters and randomly selects entire clusters, used for efficiency in large populations.
Explain the concept of multistage sampling.
Multistage sampling involves multiple levels of sampling, such as selecting clusters first and then subjects within those clusters.
What are the advantages of using probability sampling methods?
Probability sampling methods ensure that every member of the population has a known and non-zero chance of being selected.
What is non-probability sampling, and when might it be used?
Non-probability sampling does not give all members of a population a chance to be included and is used when probability sampling is not possible.
How do you calculate the sample size for a survey?
Sample size is calculated based on the desired level of precision, confidence level, and the variability in the population.
What are the potential biases in convenience sampling?
Convenience sampling can lead to underrepresentation or overrepresentation of particular groups within the sample.
How does purposive sampling differ from random sampling?
Purposive sampling involves selecting subjects based on specific characteristics, differing from random sampling which does not consider the characteristics of the subjects.
What is snowball sampling, and in what types of research is it useful?
Snowball sampling involves existing study subjects recruiting future subjects from among their acquaintances, useful in hard-to-reach populations.
Why is sampling important in research?
Sampling allows researchers to make inferences about a larger population without needing to survey everyone.
What methods can be used to ensure representativeness in a sample?
Representativeness can be ensured by using random sampling methods and by stratifying the sample to reflect population characteristics.
How can sampling error be minimized?
Sampling error can be minimized by increasing the sample size and using efficient sampling techniques.
What is quota sampling, and how does it work?
Quota sampling involves selecting people to meet certain quotas on characteristics, ensuring the sample reflects certain features of the population.
What role does sampling frame play in sampling?
The sampling frame is a list from which the sample is drawn, and its quality can significantly affect the sample’s accuracy.
How do you handle non-response in surveys?
Non-response can be handled by follow-ups, incentives, and adjusting the weights in the analysis to account for the missing responses.