Question

What is overmatching versus undermatching? Give an example of overmatching and undermatching (with hypothetical proportions) that might occur on a concurrent VI 20-sec VI 30-sec schedule (which means that you must first work out the expected proportions with these schedules).

Answer 1

The Matching law states that the response and the attainment of reinforces,on same specific schedule,are same in proportion with each other,A test pigeon represented with VI 30-sec and VI 60-sec schedules,would emit almost double the number of responses on the VI 30-sec schedule than on the other schedule.This is because the VI 30-sec schedule provides a higher rate of reinforcement.
But ,at times,there can be deviations from matching.these can be of three types,namely,undermatching,overmatching and bias from matching.
Undermacthing occurs when there is not much difference between the two alternate schedules in terms of response proportions by the test pigeon when compared with the predicted values.the proportion of responses occurring for the poorer and the richer schedules does not vary much or simply it is less different.
Example: by the matching law, the proportion of responses VI 20-sec and VI 30-seccan be easily predicted to be 0.57 and 0.43.but if these come out to be 0.50 and 0.50,respectively.then,one can see that there is less difference between the two and this has happened because of undermatching.