Positive and negative generalization gradients obtained after equivalent training conditions.

Abstract
Positive and negative gradients were compared on the dimension of angular orientation (tilt) following discrimination training with the presence of a vertical line being positive and its absence being negative for one group of pigeons, and the opposite discrimination for another group. The gradients were initially very similar in form, although the negative gradient became flatter in the course of testing. Equivalent training conditions therefore produced similar positive and negative gradients; previously obtained differences between gradients of acquisition and extinction are presumably due to differences in pretest training procedures. (PsycINFO Database Record (c) 2006 APA, all rights reserved)