Schedules of Reinforcement Flashcards
Now that we have discussed
reinforcement . . .
* It is time to discuss how reinforcements can and
should be delivered
* If you were going to reinforce your puppy for going
to the bathroom outside, how would you do it?
* Would you give him a doggie treat every time?
Some of the time?
* Would you keep doing it the same way or would
you change your method as you go along?
Now that we have discussed
reinforcement . . .
* It is time to discuss how reinforcements can and
should be delivered
* If you were going to reinforce your puppy for going
to the bathroom outside, how would you do it?
* Would you give him a doggie treat every time?
Some of the time?
* Would you keep doing it the same way or would
you change your method as you go along?
Schedules of reinforcement
- A schedule of reinforcement is the response
requirement that must be met in order to obtain
reinforcement. - Each particular kind of reinforcement schedule
tends to produce a particular pattern and rate of
performance - In other words, it is what you have to do to get the
reward! - Example: Does a dog have to roll over just once to get a
reward, or does he have to roll over more than once
before he’s given his reward?
Continuous
- Continuous – A continuous reinforcement schedule
(CRF) is one in which each specified response is
reinforced - Example: every time the dog rolls over he gets a treat
every time a child hangs up her coat she gets praised - Useful for strengthening newly learned behaviors or
when using shaping procedures to train a behavior. - Leads to rapid increases in the rate of the behavior
(begins to occur very frequently). - Not very common in a natural environment.
- Intermittent
- Intermittent
- An intermittent reinforcement schedule is one in which
only some responses are reinforced (not every
response) - Example: every third time the dog rolls over he gets
reinforced. - Useful for maintaining behaviors that are already
established - They can be based on the number of responses made
(ratio) or the time between reinforcement (interval) - They can also be fixed or variable.
Types of intermittent schedules
- Ratio Schedules
- Reinforcement given
after a number of nonreinforced responses - Fixed Ratio
- Variable Ratio
- Interval Schedules
reinforcement - given for a responses
that occurs after a
certain amount of time
has passed - Fixed Interval
- Variable Interval
- Fixed ratio schedule (FR) -
- Fixed ratio schedule (FR) - reinforcement is given after a
fixed number of nonreinforced responses (predictable) - Examples:
- FR4 schedule - a salesperson receives a bonus after
every 4 sales - FR1 schedule - take a break after reading a chapter in
the text - FR50 schedule - a rat received a food pellet after every
50 bar presses. - “piecework” - paid by number of pieces sewn together
- Schedules can be dense (e.g., FR5) or lean (e.g.,FR 50)
Fixed Ratio
Fixed Ratio
* Characteristic pattern
* Short pause following each reinforcer
* Higher ratio requirements produce longer pauses after
reinforcement
* e.g., FR50 has longer break before responding again than
FR25
* Can stretch the reinforcement ratio (e.g., FR1, FR2, FR4,
FR6, FR10)
* Ratio strain – when requirement increases too quickly
behavior becomes erratic or disrupted
* Movement from “dense” to “lean” schedules should be done gradually.
Variable ratio
- Variable Ratio (VR): Reinforcer given after variable
amount of non-reinforced responses (less predictable) - VR10 schedule, on average every 10 responses are
reinforced but number of responses might vary
between 1 and 20 - Examples
- VR6 schedule - a gambling machine pays off every 6
spins on average, but payoff trial cannot be predicted - VR50 schedule - a food pellet is dispensed on average
every 50 bar-presses, but exact trial cannot be
predicted - Salesperson working on commission
- Characteristic pattern:
- High and steady rate of response
- Little or no postreinforcer pausing (especially when
minimum requirement is low) - Behaviors on this type of schedule tend to be very
persistent - This includes unwanted behaviors like begging,
gambling - “Stretching the ratio” “schedule thinning” means
starting out with a very dense, rich reinforcement
schedule and gradually decreasing the amount of
reinforcement - The spouse, gambler, or child must work harder
and harder to get the reinforcer
Fixed interval
- Fixed Interval (FI): Reinforcement obtained on first
response after a fixed, predictable period of time - Example
- FI 2min – a rat receives food on the first lever press
following a 2 minute interval - FI75min - glancing at the clock during class. After
75 minute interval, you are rewarded by being
allowed to leave.
FI
- Characteristic Pattern:
- “scallop pattern” – FI schedules produce an
upwardly curved rate of responding with increased
rate of responding as the interval nears its end - Example: study more and more as a test
approaches. - Noticeable post-reinforcement pause
- Example: don’t study much after a test has just
occurred
Variable interval
- Variable Interval (VI): Reinforcer given for the first response
after a varying, unpredictable amount of time - VI 30 sec schedule- on average the first response after every
30 seconds is reinforced but the time of reinforcement
might vary between 1 sec & 1 min - Examples
- VI 2min - a food pellet is dispensed on the first bar-press
following a 2 minute interval (on average) but exact time
bar-press cannot be predicted - VI 15min – Hilary’s boyfriend, Michael, gets out of school
and turns on his phone some time between 3:00 and 3:30
(the aver age is after 15 minutes) – the “reward ” of his
answering his phone puts her calling behavior on a VI
schedule, so she calls every few minutes until he answers
VI
- Characteristic Pattern:
- Moderate steady rate of response
- little or no post-reinforcement pause
- Example: Presses of the “redial” button on the
telephone are sustained at a steady rate when you
are trying to reach your parents and get a “busy”
signal on the other end of the line
Schedules of Reinforcement
- Fixed-ratio
- FIXED NUMBER of
responses - Variable-ratio
- VARYING NUMBER of
responses - Usually an average
Schedules of Reinforcement
- Fixed-interval
- FIXED TIME has passed since last reward
- Variable-interval
- VARYING AMOUNTS OF TIME has passed
since last reward
F-R: Fixed Number
V-R: Varying Number
F-I: Fixed Time
V-I: Varying Time
F-R: Fixed Number
V-R: Varying Number
F-I: Fixed Time
V-I: Varying Time
