sampling error

This term is a technical expression used primarily in statistics and research methodology. It describes a natural discrepancy that occurs when a sample is used to represent a larger population, rather than a mistake made by the researcher. It is distinct from non-sampling error, which refers to flaws in data collection, such as biased questioning or data entry mistakes.

In professional reports, it is often discussed in the context of the margin of error. Because it is an inherent property of sampling, the goal of a researcher is not to eliminate sampling error entirely—which is impossible without a full census—but to minimize it by increasing the sample size or improving the sampling method.