Chapter 6
Developing Behavioral
Persistence Through the
Use of Intermittent
Reinforcement
Intermittent Reinforcement
Basic Definitions
 Continuous Reinforcement opposite of
extinction
 Intermittent Reinforcement between
extinction and continuous reinforcement
schedules
 Schedule of Reinforcement

Intermittent Reinforcement


Acquisition and Maintenance phases of
learning: use continuous during acquisition,
then intermittent schedules during maintenance.
Advantages of Intermittant over Continuous
reinforcer effective longer (satiation slower).
 more
resistant to extinction.
 individuals work more consistently on certain int.
schedules.
 persists more when transferred to natural reinforcers.
Ratio Schedules


Fixed Ratio: start with low ratio, move higher
gradually enough to avoid Ratio Strain .
Characteristics:
1) high rate of response until reinforcement
2) higher ratios increase Postreinforcement
Pause
3) high resistance to extinction
Example: piece-rate pay
Ratio Schedules

Variable Ratio : Use average ratio to define the
schedule.

Characteristics:
1) high steady rate of response
2)very little postreinforcement pause.
3)high resistance to extinction

Ratios can be increased less gradually without ratio
strain.
Examples: slot machines, asking for date, golf shot,
solitaire

Ratio Schedules

When to use Ratio Schedules?
1) To generate high rate of response
2) When each response can be monitored.
Simple Interval Schedules
Fixed-Interval : ex. FI 2-minute.
Characteristics:
1) response rate increases gradually until
reinforcement.
2) postreinforcement pause (higher FI
value=longer pause
 Examples: picking up a paycheck,
checking mail

Simple Interval Schedules



Variable-Interval Schedule : use average
interval to define
Characteristics:
1) moderate response rate
2) little post-reinforcement pause
3) higher resistance to extinction than FI
Examples: checking mail (if delivered
inconsistently) or answering machine
Simple Interval Schedules
When to use simple interval
schedules?
Rarely, due to:
 post-reinforcement pause for FI,
 lower response rates overall for VI
 continuous monitoring required for both
after the end of an interval, waiting for the
first behavior to occur.

Limited Hold
When to do limited hold?
Whenever possible, to:
1) improve response rate to that similar to
ratio scales,
2) eliminate post-reinforcement pause and
increase resistance to extinction.

Limited Hold
Add Limited Hold to interval schedules to
eliminate postreinforcement pause. (FI 1
minute/LH 10 seconds)

Response rates to interval schedules
with limited hold are like ratio schedules:
FI/LH like FR and VI/LH like VR.

Limited Hold
More resistant to extinction
Examples.
 Timer Game for kids (VI /LH),
 waiting for bus (FI/LH),
 watching TV (VI/LH),
 hitchhiking (VI/LH),
 calling friend (VI/LH)

Duration Schedules
Duration Schedules Fixed-Duration and
Variable-Duration
 Characteristics:
1) Continuous behavior
2) FD has post-reinforcement pause
3) FD mod R.T.E., VD High R.T.E.
Examples: hourly pay (FD), melting solder
(FD), rubbing sticks together (VD)

Duration Schedules
When to use?
 When target behavior can be measured
continuously and reinforced based on
duration. FR better than FD, ex. dusting







Concurrent Schedules of Reinforcement
We respond to concurrent (competing)
schedules of reinforcement all the time…what
determines which reinforcers we respond to?
How do we prioritize our time (behavior)?
immediacy of reinforcement
magnitude of reinforcement
response effort required
schedule of reinforcement
Chapter 7
Types of Intermittent Reinforcement
to Decrease Behavior
Intermittent Reinforcement to Decrease
Behavior
Differential Reinforcement of Low
Rates (DRL)
 Some behaviors are tolerable or even
good at low rates but not at high rates.

Examples: talking, confrontation, visits,
talking out in class…
Intermittent Reinforcement to Decrease
Behavior


Limited responding DRL: for undesirable
behavior (reinforce if behavior is less than a
certain limit within a certain time)
Spaced-responding DRL: for desirable
behavior that needs to be decreased to
acceptable levels (e.g. giving answer in class).
If behavior has not occurred for a specific
interval, reinforce first instance of behavior
after interval ends, then start non-reinforcing
interval again.
Intermittent Reinforcement to Decrease
Behavior

Differential reinforcement of Zero
Responding (DRO)
Reduction of DRL limit to zero
Sometimes called Differential reinforcement of
other responding because any other behavior
besides the target behavior to eliminate is OK
and is thus reinforced after a certain interval.
This can create a problem of reinforcing other
undesirable behaviors, so we can use…
Intermittent Reinforcement to Decrease
Behavior
Differential Reinforcement of
Incompatible Responding (10)

Find a desirable behavior which
cannot be done at the same time as the
undesirable behavior (see table pg. 93

This eliminates the problem of
reinforcing undesirable behaviors as
mentioned above.

Chapter 8
Doing the Right Thing at the Right Time
and Place: Stimulus Discrimination and
Stimulus Generalization
Stimulus Discrimination and Stimulus
Generalization
Stimulus Discrimination Learning

Stimulus Discrimination : emitting
behavior in certain context, and not others.

ABCs of behavior: Antecedent (stimulus
context), behavior, consequences
Stimulus Discrimination and Stimulus
Generalization
Stimulus Control : degree of correlation
between stimulus and subsequent response
 Discriminative stimuli
SD or stimulus for reinforcement
Sdelta or “
“ extinction
Examples:
swearing with friends, friends are SD
swearing at Grandparents, GPs are Sdelta

Stimulus Discrimination and Stimulus
Generalization
Stimulus Generalization
Physical Similarity: stimulus class
Common characteristics: stimulus
class, concept
Equivalence class
Stimulus Discrimination and Stimulus
Generalization
Factors determining effectiveness of
Stimulus Disc. Training
1) Distinct Signals: not easily confused,
high attention value, salient
2) Minimizing opportunities for error
structure environment carefully to avoid
responses to Sdeltas
3) Maximize number of trials:
4) Use Rules: Describe the contingencies