Keskihajontaan

Keskihajontaan is the illative form of the Finnish noun keskihajonta. Keskihajonta is a statistical term referring to a measure of dispersion that describes how far data points spread around the central value, typically the mean. In practical terms, it indicates how tightly or loosely data are clustered in relation to the center.

Linguistically, -aan in Finnish marks the illative case, which expresses direction toward or reference to a concept or object. Therefore keskihajontaan is not a separate concept by itself; it is the grammatical form used when the standard deviation is the target of discussion or action in a sentence. For example, you might encounter phrases like keskihajontaan liittyvät mittarit or keskihajontaan vaikuttavat tekijät.

In statistical use, keskihajonta is commonly distinguished as population keskihajonta (σ) and sample keskihajonta (s). The population standard deviation is defined as σ = sqrt( Σ (x_i − μ)^2 / N ), where μ is the population mean and N is the number of observations. The sample standard deviation is defined as s = sqrt( Σ (x_i − x̄)^2 / (n − 1) ), where x̄ is the sample mean and n is the sample size. These formulas quantify dispersion around the central tendency of the data and are fundamental in fields such as science, engineering, and economics.

See also: standard deviation, statistics, data dispersion.