<Li> Reinforcement hierarchy is a list of actions, rank - ordering the most desirable to least desirable consequences that may serve as a reinforcer . A reinforcement hierarchy can be used to determine the relative frequency and desirability of different activities, and is often employed when applying the Premack principle . </Li> <Li> Contingent outcomes are more likely to reinforce behavior than non-contingent responses . Contingent outcomes are those directly linked to a causal behavior, such a light turning on being contingent on flipping a switch . Note that contingent outcomes are not necessary to demonstrate reinforcement, but perceived contingency may increase learning . </Li> <Li> Contiguous stimuli are stimuli closely associated by time and space with specific behaviors . They reduce the amount of time needed to learn a behavior while increasing its resistance to extinction . Giving a dog a piece of food immediately after sitting is more contiguous with (and therefore more likely to reinforce) the behavior than a several minute delay in food delivery following the behavior . </Li> <Li> Noncontingent reinforcement refers to response - independent delivery of stimuli identified as reinforcers for some behaviors of that organism . However, this typically entails time - based delivery of stimuli identified as maintaining aberrant behavior, which decreases the rate of the target behavior . As no measured behavior is identified as being strengthened, there is controversy surrounding the use of the term noncontingent "reinforcement". </Li>

The rate of a behavior increases because a stimulus is removed following that behavior