Question

Suppose a famous person reads every 12th letter of the 45 thousand letters coming in weekly. What type of sampling design is the person using in this​ case? Explain your answer.
What type of sampling is​ used?
A.
The person is using simple random sampling because a random letter is chosen each week.
B.
The person is using cluster​ sampling, where each week is a cluster of letters.
C.
The person is using convenience sampling because the letter chosen is the easiest one to get.
D.
The person is using stratified​ sampling, where the strata are the days of the week.
E.
The person is using systematic sampling because the sample is chosen using a fixed periodic interval.

Answer 1

A) This is not a case of simple random sampling as there is a rule for sampling here, we are selecting every 12th letter here. Simple random sampling would have been selecting any of the letters without any rule.

B) There are no clusters or a specific groups of letters defined here, therefore this cannot be a cluster sampling

C) it is not convenience sampling as all the letters as such are already given, no rule would have been required.

D) For stratified sampling we select a sample of items from each group, again there is no group defined here, and therefore stratified sampling is also incorrect.

E) As we are making the selection with specific rules, therefore this is a case of systematic sampling.