Discriminant Function Analysis - Effect Size

Effect Size

Some suggest the use of eigenvalues as effect size measures, however, this is generally not supported. Instead, the canonical correlation is the preferred measure of effect size. It is similar to the eigenvalue, but is the square root of the ratio of SSbetween and SStotal. It is the correlation between groups and the function. Another popular measure of effect size is the percent of variance for each function. This is calculated by: (λx/Σλi) X 100 where λx is the eigenvalue for the function and Σλi is the sum of all eigenvalues. This tells us how strong the prediction is for that particular function compared to the others. Percent correctly classified can also be analyzed as an effect size. The kappa value can describe this while correcting for chance agreement.

Read more about this topic:  Discriminant Function Analysis

Famous quotes containing the words effect and/or size:

    An actor must communicate his author’s given message—comedy, tragedy, serio- comedy; then comes his unique moment, as he is confronted by the looked-for, yet at times unexpected, reaction of the audience. This split second is his; he is in command of his medium; the effect vanishes into thin air; but that moment has a power all its own and, like power in any form, is stimulating and alluring.
    Eleanor Robson Belmont (1878–1979)

    Delusions that shrink to the size of a woman’s glove,
    Then sicken inclusively outwards:
    . . . the incessant recital
    Intoned by reality, larded with technical terms,
    Each one double-yolked with meaning and meaning’s rebuttal:
    For the skirl of that bulletin unpicks the world like a knot....
    Philip Larkin (1922–1986)