Comparator Hypothesis

The comparator hypothesis, also known as comparator theory, is a Pavlovian behaviorist model regarding the relationship between performance and associative learning that was first proposed by Ralph Miller.

This hypothesis proposes that competition effects are evident during the time of the performance or test and NOT during the actual learning phase. This means that while undergoing conditioning the organism acquires not only the conditioned stimulus (CS) and unconditioned stimulus (US) associations but also a contextual/environmental and US association -- during a test a response to a CS will only occur if the association between the CS-US is stronger than the contextual-US pairing. The comparator hypothesis allowed for explanations and modifications for other behaviorist models such as the Rescorla-Wagner model.