Identify the sampling techniques used, and discuss potential sources of bias (if
ID: 3049599 • Letter: I
Question
Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain. Lettuce is planted on a 55-acre field. The field is divided into one-acre subplots. A sample is taken from each subplot to estimate the harvest. What type of sampling is used? A. Stratified sampling is used, since the field is divided into subplots and a random sample is taken from each subplot. B. Convenience sampling is used, since the lettuce plants closest to the barn are sampled. C. Cluster sampling is used, since the field is divided into subplots, a number of subplots are selected, and every lettuce plant in the selected subplots is sampled. D. Simple random sampling is used, since each sample of lettuce plants of the same amount has the same chance of being selected. What potential sources of bias are present, if any? Select all that apply. A. It is possible that, due to sampling error, the sample will not be representative. B. Certain subplots may have more or fewer lettuce plants than others. Samples from these subplots may bias the overall sample. C. The sample only consists of the lettuce plants that are easiest to reach. This may not be representative of the entire population. D. There are no potential sources of bias.
Explanation / Answer
(1)
Correct option:
A. Stratified ampling is used, since the field is divided into subplots and a random sample is taken from each subplot.
EXPLANATION: In sratifiedsampling, the researcher divides the population into seperate groups, called strata and a random sample is drawn from each group.
(2)
Correct option:
B. Certain subplots may have more or fewer lettuce plants than others.Samples from the sesubplots may bias the overall sample.
EXPLANATION: Since the lettuce plants are not present uniformly in all subplots, taking one sample from each subplot may create bias. In such situations, quota sampling will avoid this bias.