Which statement best describes a population parameter?

Which statement best describes a population parameter?

• A. A fixed descriptive value of the entire population.
• B. A descriptive value based on a sample.
• C. A random variable representing population data.
• D. A measure of sampling error.

Answer: (A)

A population parameter is a fixed value that describes a characteristic of the entire population. This means it remains constant for that population, even though we usually don’t know its exact value and must estimate it from samples. In contrast, a descriptive value based on a sample is a statistic, which can vary from sample to sample because different samples yield different estimates. A random variable representing population data would describe the data you could observe in the population, but the parameter itself is not random. A measure of sampling error refers to how far an estimate is from the parameter, not the parameter itself. So the best description is a fixed descriptive value of the entire population.

A population parameter is a fixed value that describes a characteristic of the entire population. This means it remains constant for that population, even though we usually don’t know its exact value and must estimate it from samples. In contrast, a descriptive value based on a sample is a statistic, which can vary from sample to sample because different samples yield different estimates. A random variable representing population data would describe the data you could observe in the population, but the parameter itself is not random. A measure of sampling error refers to how far an estimate is from the parameter, not the parameter itself. So the best description is a fixed descriptive value of the entire population.