Jump to content

Parametric statistics

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Stonemaccas (talk | contribs) at 05:12, 19 September 2006. The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Parametric inferential statistical methods are mathematical procedures for statistical hypothesis testing which assume that the distributions of the variables being assessed belong to known parametrized families of probability distributions. In that case we speak of parametric model.

For example, analysis of variance assumes that the underlying distributions are normally distributed and that the variances of the distributions being compared are similar. The Pearson product-moment correlation coefficient assumes normality.

While parametric techniques are robust – that is, they often retain considerable power to detect differences or similarities even when these assumptions are violated – some distributions violate the assumptions so markedly that a non-parametric alternative is more likely to detect a difference or similarity.

Examples of parametric tests include: