One of the characteristics of probability sampling is:

Concept

Probability sampling uses a chance-based selection rule. Each eligible unit has a known, non-zero probability of inclusion, so selection is not left to the researcher’s convenience or judgment.

This random mechanism is the defining feature; it supports probability-based estimates of sampling error and population inference.

Application

Among the listed values, random selection is the one that names this chance mechanism. Therefore it is the characteristic associated with probability sampling.

Contrast

• Population bias describes a mismatch between the target population and the population represented by the sampling frame; it is a source of distortion, not a selection mechanism.

• Sampling bias is systematic over- or under-representation caused by the selection process; probability designs are intended to control this risk rather than define themselves by it.

• Accidental selection chooses units encountered or readily available, which is a convenience-based non-probability approach.

Cross-check

A chance-based rule gives every eligible unit a known, non-zero inclusion probability. Replacing it with interviewer judgment or convenience removes that defining property.

Result

The characteristic is random selection.