Practically significant relationships between two variables

Abstract

It is shown how effect sizes can be used to establish whether relationships between two variables are practically significant (important). This is done for populations as well as for samples. Four cases are distinguished: When both variables are nominal, both dichotomous, one dichotomous and the other on an interval scale and lastly both variables on an interval scale. Examples are given to illustrate the use of the suggested effect sizes. Opsomming Daar word aangetoon hoe effekgroottes gebruik kan word om te bepaal of verbande tussen twee veranderlikes prakties betekenisvol (belangrik) is. Dit word vir populasies sowel as vir steekproewe gedoen. Vier gevalle word onderskei: Wanneer albei veranderlikes nominaal, albei digotoom, een digotoom en die ander op ‘n intervalskaal en laastens albei veranderlikes op ‘n intervalskaal is. Voorbeelde word gegee om die gebruik van die voorgestelde effekgroottes te illustreer.