| ||||

SMABS 2004 Home Organization About Jena Sponsors Links Imprint / Contact SMABS Home |
## Contributions: Abstract## Myths and paradoxes in the realm of classical test theory
The construction of most psychological tests is based on two principles: aggregation and the elimination of items with low item-scale correlations. It is shown that this practice cannot be justified by the formulas of classical test unless very strong assumptions hold. If the items under consideration are not It is argued that this hitherto unnoticed kind of attenuation paradox is likely to occur in practice whereas the constellations discussed so far are practically irrelevant. Paradoxical effects of item selection with regard to item-scale correlations are also discussed. It is concluded that the conventional method of scale construction is not founded on statistical theorems but on (more or less implicit) assumptions that are logically inconsistent. Therefore, this practice should rather be called naïve than classic. |