Psychology with Mr. Duez CH 6: Learning - Operant Conditioning --- Schedules of Reinforcement
Operant conditioning (instrumental conditioning) involves an organism’s learned response in order to obtain a reward.
The response is an action not typically associated with obtaining a particular reward.
B.F. Skinner (Rats/Pigeons) pioneered the study of operant conditioning, although the phenomenon 1st was discovered by Edward L. Thorndike (Cats), who proposed The Law of Effect, which states that a behavior is more likely to recur if reinforced. Skinner ran many operant-conditioning experiments. He often used a specially designed testing apparatus known as a Skinner Box.
Behaviorists use various “Schedules of Reinforcement”: Specific pattern of reinforcers over time. In a continuous reinforcement schedule, every correct response that is emitted results in a reward. This produces rapid learning, but also results in rapid extinction, where extinction is a decrease & eventual disappearance of a response once the behavior is no longer reinforced.
Schedules of reinforcement in which not all responses are reinforced are called partial (or intermittent) reinforcement schedules.
RATIO = After a certain NUMBER of responses.
INTERVAL = After a certain TIME period.
Fixed-Ratio schedule: Reward always occurs after a fixed number of responses.
Produces strong learning, but the learning extinguishes relatively quickly.
Variable-Ratio schedule: Ratio of responses to reinforcement is variable & unpredictable. Reinforcement can come at any time. Takes longer to condition a response; however the learning that occurs is resistant to extinction.
Fixed-Interval schedule: Reinforcement is presented as a function of fixed periods of time, as long as there is at least one response.
Variable-Interval schedule: Reinforcement is presented at differing time intervals, as long as there is at least one response. Variable-interval, like variable-ratio, is more difficult to extinguish than fixed schedules.
Chart demonstrates the different response rate of the 4 simple schedules of reinforcement, each hatch mark designates a reinforcer being given.
When & how often we reinforce a behavior can have a dramatic impact on the strength and rate of the response.
In real-world settings, behaviors are probably not going to be reinforced each and every time they occur. For situations where you are purposely trying to train & reinforce an action, such as in the classroom, in sports or in animal training, you might opt to follow a specific reinforcement schedule.
Some schedules are best suited to certain types of training situations. In some cases, training might call for starting out with one schedule & switching to another once the desired behavior has been taught.
Schedules of Reinforcement Examples: For each example below,
decide whether the situation describes
fixed ratio (FR), fixed interval (FI) or
variable ratio (VR), variable interval (VI)
schedule of reinforcement situation.
Note: Examples are randomly ordered, & there are not equal numbers of each schedule of reinforcement.
F or V
R or I
Getting paid $10 for every 20 puzzles solved.
Studying for a class that has surprise quizzes.
Slot machines are based on this schedule.
Speed traps on highways.
Selling a product door to door.
The boss hands out a sales bonus check every time he’s in a good mood.
Getting a paycheck at the end of every 2-week pay period.
End of the year “Holiday Bonus” check.
Angelina gives Brad a kiss after the end of every lap he swims in the pool.
Torchy’s Taco loyalty card: Free taco after 10 taco purchases.
A child screams and cries at the candy counter--sometimes it works & mom buys him candy.
Annual Black Friday Promotion: Free iPod with a purchase of an iPhone at Walmart.
Getting a strike in bowling.
Random drug testing in the NFL - Summer, Fall, Winter dates for random players.
Fixed = Specific
Variable = Unpredictable
Ratio = Number #
Interval = Time Period
FR: Fixed Ratio = Specified Number # of Responses
FI: Fixed Interval = Specified Number # during Time Period
VR: Variable Ratio = Unpredictable Number # of Responses
VI: Variable Interval = Unpredictable Time Period