Which term describes a value—usually numerical—that describes a population?

Which term describes a value—usually numerical—that describes a population?

• A. Statistic
• B. Sampling error
• C. Parameter
• D. Sample

Answer: (C)

A parameter is a numerical value that describes a characteristic of an entire population. It represents something like the population mean or population variance, the true values that define the whole group. Parameters are usually unknown because we can’t measure every member of the population, so we use statistics—numbers calculated from a sample—to estimate them. For example, the sample mean provides an estimate of the population mean. The difference between the statistic and the true parameter arises from sampling variability and is called sampling error. A sample, by contrast, is just the subset we actually observe. So the term that describes a population value is parameter.

A parameter is a numerical value that describes a characteristic of an entire population. It represents something like the population mean or population variance, the true values that define the whole group. Parameters are usually unknown because we can’t measure every member of the population, so we use statistics—numbers calculated from a sample—to estimate them. For example, the sample mean provides an estimate of the population mean. The difference between the statistic and the true parameter arises from sampling variability and is called sampling error. A sample, by contrast, is just the subset we actually observe. So the term that describes a population value is parameter.