Operant Conditioning• A type of learning in which behavior is

strengthened if followed by reinforcement or diminished if followed by punishment.

Edward Thorndike

• Law of Effect: rewarded behavior is likely to recur.

• 1905

Thorndike’s Puzzle Box

B.F. Skinner(March 20, 1904 – August 18, 1990)

Operant Conditioning ChamberSkinner Box 1948

Skinner Reinforcement Schedules

• Continuous Reinforcement: every time rat does a behavior he gets food.

• Fixed ratio: if rat presses lever three times he gets food.

• Fixed interval: if rat presses lever once during a fixed time period – 30 seconds, he gets food.

Even if he presses lever 100 times he get only one food pellet.

Skinner Reinforcement Schedules

• Variable ratio: first it take 3 lever presses to get food, then 10, then 1, then 15, and so on.

(focus on animal’s behavior)• Variable interval: the administrator of the food

keeps changing the time period to receive food. First 20 seconds, then 45 seconds, then 10 seconds and so on.

(focus on time period for rewards)

Classical v. Operant• They both use acquisition, discrimination, SR,

generalization and extinction.•Classical Conditioning is automatic (respondent behavior). Dogs automatically salivate over meat, then bell- no thinking involved.

•Operant Conditioning involves behavior where one can influence his/her environment with behaviors which have consequences (operant behavior).

Shaping

• A procedure in Operant Conditioning in which reinforcers guide behavior closer and closer towards a goal.

REINFORCEMENT PUNISHMENTPo

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Reinforcer• Any event that STRENGTHENS the behavior it follows. A

stimulus or event that affects the likelihood that a behavior will REPEATED

Two Types of Reinforcement:

Positive and Negative

Types of Reinforcements:Positive Reinforcement

• Anything that increases the likelihood of a behavior by following it with a response.

• Something ADDED

Types of Reinforcements:Negative Reinforcement

• Anything that increases the likelihood of a behavior by following it with the removal of an undesirable event or state

• Taking away something you don’t like in order to make a behavior more likely

Wearing seat belt to stop dinging

Faking sick to leave school

Sleep if tiredRunning inside with cold weather

“I won’t make you do your chores IF you come to your grandmother’s this weekend instead of hang with your friends”NOT THE SAME AS PUNISHMENT!!

Punishment

Adding or subtracting something you don’t like in order to make a behavior less likely.

Unpleasant and negative consequence (stimulus) is added or removed to stop behavior

DECREASE an undesirable behavior.

Two types of PunishmentsPositive and Negative

Type of PunishmentPositive Punishment

Direct Delivery of Punishment- An averse stimulus is delivered /added IMMEDIATELY following a behavior.

Spanking “I’ll smack you across the face if you don’t stop talking

back to your mother. “ Jail The teacher reprimands you with a detention for

breaking the dress code

Type of PunishmentNegative Punishment

Omission Training/Response Cost

Removing (stimulus) something enjoyable with intent to DECREASE behavior.

A positive event or object is usually removed

Time outsTaking car awayTaking phone awayTake away privileges.

.

TRY IT!!a. Billy likes to campout in the backyard. He camped-

out on every Friday during the month of June. The last time he camped out, some older kids snuck up to his tent while he was sleeping and threw a bucket of cold water on him. Billy has not camped-out for three weeks

1. What behavior was changed? 2. Was the behavior strengthened or weakened? 3. What was the consequence? 4. Was the consequence added or subtracted?Positive Reinforcement, Negative Reinforcement, Response

Cost/Negative Punishment, Positive Punishment

l. What behavior was changed? camping-out

2. Was the behavior strengthened or weakened? weakened (eliminate positive and negative reinforcement)

3. What was the consequence? having water thrown on him

4. Was the consequence added or subtracted? Added

ANSWER: Since a consequence was added and the behavior was weakened, the process was Positive Punishment.

Try It!b. Every time Madge raises her hand in class she is called on.

She raised her hand 3 time during the first class, 3 times in the second and 4 times during the last class.

l. What behavior was changed? 2. Was the behavior strengthened or weakened?3. What was the consequence? 4. Was the consequence added or subtracted? • Positive Reinforcement, Negative Reinforcement, Negative

Punishment /Response Cost, Positive Punishment

1. What behavior was changed? Hand raising

2. Was the behavior strengthened or weakened? Strengthened

3. What was the consequence? Being called on

4. Was the consequence added or subtracted? Added

ANSWER: Since the consequence was added and the behavior was strengthened, the process is positive reinforcement.

TRY IT!!c. When Greg follows a direction / command he earns a

point. At the end of each day, he can "buy" free time, TV. privileges, etc. with his points. When he misbehaves or doesn't follow a command, he loses points. Greg used to call his mom names. Since he has been on the point system, his name calling has been reduced to almost zero.

1. What behavior was changed? 2. Was the behavior strengthened or weakened? 3. What was the consequence? 4. Was the consequence added or subtracted?Positive Reinforcement, Negative Reinforcement, Response

Cost/Negative Punishment, Positive Punishment

1. What behavior was changed? Calling his mom names

2. Was the behavior strengthened or weakened? Weakened (eliminate positive and negative reinforcement)

3. What was the consequence? Losing points

4. Was the consequence added or subtracted? Subtracted

ANSWER: Since the consequence was subtracted and the behavior was weakened, the process is negative punishment / response cost.

TRY IT!!d. John does not go to the dentist every 6-months

for a checkup. Instead, he waited until a tooth really hurts, then goes to the dentist. After two emergency trips to the dentist, John now goes every 6-months.

1. What behavior was changed? 2. Was the behavior strengthened or weakened? 3. What was the consequence? 4. Was the consequence added or subtracted?Positive Reinforcement, Negative Reinforcement, Response

Cost/Negative Punishment, Positive Punishment

1. What behavior was changed? going to the dentist

2. Was the behavior strengthened or weakened? strengthened (eliminate response cost / negative punishment)

3. What was the consequence? tooth no longer hurting

4. Was the consequence added or subtracted? Subtracted

ANSWER: Since the consequence was subtracted and the behavior was strengthened, the process is negative reinforcement.

Reinforcement SchedulesTiming and Frequency are important

Continuous Reinforcement• Reinforcing the desired response every time it occurs.

Rewards follow every correct response!!• + = great for new behaviors• - = easy to extinguish

Quick Acquisition

Quick Extinction

Partial Reinforcement

• Reinforcing a response only part of the time. Rewards follow only some correct responses

• The acquisition process is slower.

• Greater resistance to extinction.

• Ratio and Interval

Skinner’s Reinforcement Schedules(Partial Reinforcements)

• Ratio - refers to the amount of times a behavior must be performed before it is reinforced.

• Interval- refers to the amount of time that has passed before reinforcement occurs

Fixed Variable

Ratio

Interval

.

Fixed-ratio Schedules• A schedule that reinforces where a response is given only after a

specified number of responses. Reinforcement is given after the subject performs a behavior a fixed # of times.

Example: I give cookie monster a cookie every FIVE times he sings “C is for cookie”.

Variable-ratio Schedule• A schedule of reinforcement that

reinforces a response after anunpredictable number of responses. The number of

times the subject must

perform a behavior

before being rewarded is

unknown or random.

Example: I give Homer a donut at random times when he says “DOH!!!”

Fixed-interval Schedule• A schedule of

reinforcement that reinforces a response only after a specified time has elapsed.

Example: Waiting for a bus. Buses are supposed to arrive at stops at fixed intervals, and the passenger will miss the bus if they are not there at the time the bus arrives.

Variable-interval Schedule• A schedule of

reinforcement that reinforces a response at unpredictable time intervals. A behavior is only reinforced if performed after an unknown amount of time has passed.

Pop Quizzes

Fixed(predictable)

Variable(changes, random)

Ratio

paying a worker every time they make 10 items.

Collecting Tokens in a Video Game: In many video games, you have to collection so many tokens in order to receive some type of prize.

slot machine at a casino.

Sales bonuses: Call centers often offer random bonuses to employees. Workers never know how many calls they need to make in order to receive the bonus, but they know that they increase their chances the more calls or sales they make

Interval

A weekly paycheck is a good example of a fixed-interval schedule. The employee receives reinforcement every seven days

Quiz every Friday

Rats get food every 60 seconds with bar push

Don’t study until Thursday night

Fishing requires a great deal of patience because the fisherman never knows when a fish will get caught on the hook.

Pop quiz

Checking Your Email: Typically, you check your email at random times throughout the day instead of checking every time a single message is delivered

Study little all week

Reinforcement