Exercise 2: Identifying Probability and Nonprobability Sampling Methods in Studies
1. Probability, simple random sampling. Each department was in the target was identified
by a number that had been selected from a random numbers table.
2. Yes, the sample is representative. Probability sampling allows every person or element of
the study population to be represented without researcher bias and minimizes sampling error.
3. Nonprobability, convenience sampling. In convenience sampling, subjects are enrolled in
the study until the target sample size is reached. Convenience sampling does not allow for the
opportunity to control for sampling errors and biases.
4. Nonprobability, network or snowball sampling. Network or snowball sampling makes use
of social networks and the fact that friends often have common characteristics. The selected
individuals were asked to locate other substance abusers they knew to participate in the
study.
5. Probability; stratified random sampling. Stratified random sampling is used when the
researcher knows some of the variables within a population that will affect the representatives
of the sample.
1. Probability, simple random sampling. Each department was in the target was identified
by a number that had been selected from a random numbers table.
2. Yes, the sample is representative. Probability sampling allows every person or element of
the study population to be represented without researcher bias and minimizes sampling error.
3. Nonprobability, convenience sampling. In convenience sampling, subjects are enrolled in
the study until the target sample size is reached. Convenience sampling does not allow for the
opportunity to control for sampling errors and biases.
4. Nonprobability, network or snowball sampling. Network or snowball sampling makes use
of social networks and the fact that friends often have common characteristics. The selected
individuals were asked to locate other substance abusers they knew to participate in the
study.
5. Probability; stratified random sampling. Stratified random sampling is used when the
researcher knows some of the variables within a population that will affect the representatives
of the sample.
