As the process runs, further sample means are plotted on the control chart.

The sample mean is thus more efficient than the sample median.

An alternative to the sample mean is the sample median.

The sample mean is used as an estimate of the population mean.

Note that the result of this will be different from the sample mean of the ungrouped data.

Thus the sample mean is a random variable, not a constant, and consequently has its own distribution.

The sample mean could serve as a good estimator of the population mean.

For example, the sample mean is the usual estimator of a population mean.

For example, consider two surveys of household income that both result in a sample mean of $50,000.

The sample mean may differ from the population mean, especially for small samples.