FREQUENCY DISTRIBUTION OF INTERRESPONSE TIMES DURING VI AND VR REINFORCEMENT.

KINTSCH (1965) watched how fast responses came after each reinforcer on VI and VR schedules.

The team measured the tiny gaps between responses, called inter-response times (IRTs).

They wanted to see if timing patterns differ once the first post-reinforcer response is out of the way.

After the first response, the IRT pictures looked almost the same under VI and VR.

There was no clear chain effect; one short gap did not predict the next.

In plain words, the two famous schedules feel the same to the organism once responding is rolling.

Delamater et al. (1986) later showed adult humans also treat VR like VI plus a feedback loop, giving the same response rate.

Lincoln et al. (1988) then wrapped both schedules into one math model, turning the 1965 observation into equations you can plug into a spreadsheet.

Davison et al. (1984) warn that concurrent VI VR "matching" can be an artifact of the schedule itself, so equal IRTs do not always mean equal choice rules.

If VI and VR produce the same micro-timing, you can pick either schedule for ease of use without fear of hidden response drag.

Swap in VR when you need faster acquisition, stay with VI when you want steady maintenance, and expect similar post-reinforcer pauses either way.