"An experiment was performed to test four alternative interpretations of the influence of judges' attitudes on equal-appearing interval scale values. The experimental design involved manipulation of the item series as well as judges' attitudes . . . perceptual vigilance and assimilation-contrast, can account for the obtained main effect due to judges' attitudes . . . adaptation level, can account for that effect, as well as the observed effect due to item series. Only . . . variable series, can account for both main effects and the significant interaction . . . between judge's attitudes and item series." (PsycINFO Database Record (c) 2006 APA, all rights reserved)