Schedules of reinforcement• Refers to the: frequency & manner in which

desired response is reinforced. • Continuous reinforcement - reinforcing every

correct response• Essential during acquisition phase, • Leads to the most rapid acquisition • Once a correct response consistently occurs, a

different reinforcement schedule can be used i.e.• Partial reinforcement – reinforcing some, not all

correct responses

Fixed Ratio• Reinforcement given after a set

(fixed), unvarying # (ratio) of desired responses

• Often used in work for commission or rate of production – e.g. $10 for every 100 newspapers sold

• Produces the fastest response rate and is effective in increasing worker output

• Although response rate is erratic• Less resistant to extinction than

variable ratio

Delivery of food pellet after every fifth pressing of response lever (i.e..

a fixed ratio)

Variable Ratio• Reinforcer given after irregular (variable) # of correct responses

(ratio)• E.g. average of 10 for every 100 correct responses – but randomly

given• Produces a steady response rate• More effective than fixed ratio, because of uncertainty of

reinforcement• More resistant to extinction than Fixed ratio

e.g. poker machines

Fixed interval• Delivery of reinforcer after set

period of time after correct response made.

• Produces erratic response rate • i.e. high the time just before

reinforcer is due; low the time just after that.

• E.g. getting paid $10 per hour worked

• Less resistant to extinction that variable interval

Variable interval• Reinforcer given after irregular

(variable) periods after correct response (e.g. on average every 10 sec’s – but with variations from 4 to 16 sec’s)

• Results in a low but steady response rate

• More resistant to extinction than fixed interval

Partial Schedules of Reinforcement summary