Variable ratio reinforcement schedule

One approach is to find a means to reinforce the desired behaviour, preferably on a variable ratio schedule. One such example was reported from a factory in Liverpool (see Chapter 3). The introduction of a prize draw, based upon tokens collected for attendance, led to the reduction of absenteeism levels to almost zero. Other schemes have used cash bonuses for those attending on days chosen at random during the month. Both of these types of schemes use variable ratio reinforcement - one by means of a draw, the other by the random choice of the day on which attendance is rewarded. (It is worth noting that both also required attendance at the required starting time, thus also reinforcing punctuality.)... 

There are four simple schedules of reinforcement the fixed interval (FI) and the variable interval (VI), both of which are temporally based reinforcement schedules, and the fixed ratio (FR) and the variable ratio... 

Figure 9 Schematic cumulative records of performance on the fixed ratio (FR), variable ratio (VR), fixed interval (FI), and variable interval (VI) schedules of reinforcement. Responses are cumulated vertically over time. Each downward deflection of the pen represents reinforcement delivery horizontal lines indicate pausing. (Reproduced from Seiden LS and Dykstra LA (1977) Psychopharmacology A Biochemical and Behavioral Approach. New York, NY Van Nostrand Reinhold.)...

Variable ratio schedule delivers reinforcement after a changing number of responses... 

In the habit modality, response is mainly controlled by stimuli that precede rather than follow it (outcomes) (Dickinson, 1994). As a result of this, devaluation of response outcome fails to impair habit responding. Habit responding takes place as a result of exhaustive training on high ratio schedules or under variable interval schedules where reinforcement is loosely related to response (Dickinson, 1994). 

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