Which statement best describes the relationship between a sample and a population?

Which statement best describes the relationship between a sample and a population?

• A. A sample is a subset of the population
• B. A population is a subset of the sample
• C. A sample includes all members of the population
• D. A population is defined by the sample

Answer: (A)

In statistics, the population is the entire group you’re interested in studying, while a sample is a subset drawn from that population and used to learn about the whole group. So the best description is that a sample is a subset of the population. This distinction lets researchers collect manageable data and then make inferences about population parameters like averages or proportions. The other ideas don’t fit: a population isn’t a subset of the sample, because that would imply the group is smaller than the data you collected. A sample including all members of the population would be the whole population itself—a census, not a sample. And defining a population by the sample reverses the relationship; the population should be defined by the group of interest, not by the data you happened to collect from a sample.

In statistics, the population is the entire group you’re interested in studying, while a sample is a subset drawn from that population and used to learn about the whole group. So the best description is that a sample is a subset of the population. This distinction lets researchers collect manageable data and then make inferences about population parameters like averages or proportions.

The other ideas don’t fit: a population isn’t a subset of the sample, because that would imply the group is smaller than the data you collected. A sample including all members of the population would be the whole population itself—a census, not a sample. And defining a population by the sample reverses the relationship; the population should be defined by the group of interest, not by the data you happened to collect from a sample.