Probabilistic Sampling

A sampling method in which every member of a population has a known, non-zero probability of being selected for the sample. In accessibility evaluation, probabilistic sampling of web pages allows auditors to make statistically valid generalisations about the overall accessibility of a website based on the evaluated sample. This contrasts with the non-probabilistic approach used in WCAG-EM, where auditors manually select pages, introducing potential bias and preventing confident extrapolation of results to unexamined pages.