If the food pellets are delivered when the lever is pressed in unpredictable occasions, this is called Partial reinforcement.
In the process of conditioning in psychology, an organism learns to associate a response with a particular stimulus. Each time the stimulus is presented, the organism is conditioned to respond in a certain way.
A situation whereby the rat receives food pellets for pressing a lever, but only on unpredictable occasions is called Partial reinforcement.
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