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Developed by American psychologist B.F.Skinner Revolt against “no stimulus, no response” Called as operant conditioning as it is based on certain operation the organism has to carry out Also called instrumental conditioning as some action of the learner is instrumental in bringing about a change in the environment For a response to happen the presence of a stimulus is not essential Two types of responses or behaviours In respondent behaviour the responses are elicited by known stimuli. In operant behaviour responses are emitted by unknown stimuli In respondent behaviour the stimulus precedes the response and is responsible for causing the behaviour. In operant behaviour stimulus is unknown Experiment • Skinner designed a special apparatus known as Skinner’s box • He placed a hungry rat in the box • Pressing of a bar in the box to get food is the desired response • The rat was rewarded for each of its proper attempts for pressing the lever • The lever press response was rewarded and whenever it repeated it was again rewarded and finally rat learned the art of pressing the lever Definition • Skinner designs operant conditioning as a process in which the behaviour of an organism is an emitted rather than elicited one and is strengthened in the sense of becoming more likely or frequent to occur, through reinforcement. • The basic law type R conditioning is that, “if the occurrence of an operant is followed by the presentation of a reinforcing stimulus, the strength of that operant is increased Reinforcement o o o The concept of reinforcement is the central idea in operant conditioning Any thing which has the effect of strengthening successful behavior is known as reinforcer Reinforcement in Skinner’s view is a process in which the stimulus follows a response and increases the probability of that response to appear again Types of Reinforcers A reinforcer is the stimulus whose presentation or removal increases the probability of a response reoccurring. There are two types of reinforcer – positive and negative. A positive reinforcer is any stimulus, the introduction or presentation of which increase the likelihood of a particular behavior. eg: praise, prize, smile, encouragement, rewards, awards. Negative reinforcer is any stimulus the removal or withdrawal of which increases the likelihood of a particular behavior. Eg: reproof, critical remarks etc. Schedules of Reinforcement The term schedule of reinforcement refers to the particular pattern according to which reinforcers follow responses. Continuous reinforcement schedule: reinforce every correct response Fixed interval reinforcement schedule: reward a right response made only after an interval of time. Variable interval reinforcement schedule: reinforcement is given at varying intervals of time Fixed ratio reinforcement schedule: reinforcement is given after a fixed number of response Shaping Through shaping it is possible to speed up operant conditioning and can condition quite complex response. In some situation where the desired responses do not occur at random, efforts are made for eliciting the appropriate responses. Shaping is a sort of gradual nurturing of correct responses. It is a method of successive approximations since the steps are approximations of the final responses. Skinner shaped the behavior of a pigeon – by teaching it to walk in a figure 8 to get food. Classical Conditioning It helps in the learning of respondent behaviour S conditioning as it emphasize on stimulus There is pairing of UCS and CS Reinforcement comes first The essence of learning is stimulus substitution Operant Conditioning It helps in the learning of operant behaviour R conditioning as it emphasize on response There is no pairing of UCS and CS, but pairing of a response and the reinforcing stimulus which follows Reinforcement is provided after the response is made by the organism The essence of learning is response modification