🚀 go-pugleaf

[From Bruce Abbott (990507.1010 EST)]

>Richard Kennaway (990507.1439 BST) --

>I'm not clear on what these mean.  Assuming an experiment involving
>lever-pressing to get food-pellets, with each lever yielding identical
>pellets, is Ra the rate of delivery of pellets per unit time, or per press?

Ra is the rate of delivery of pellets per unit time.

>I think Bill's analysis in [(990506.1225 MDT)] took it as per unit time (in
>which case the matching law makes no sense -- Ra/rA is pellets per unit
>time/presses per unit time = pellets per press, a property of the lever
>independent of the rat).

Ra/rA would indeed be a property of the "lever" (schedule associated with
the lever) independent of the rat if the schedule in question were a ratio
schedule, which imposes a particular ratio of lever-presses per pellet
delivery.  On other schedules this ratio will depend on the rate of
lever-pressing.  For example, on a variable-interval schedule having a
maximum interval of 60 seconds, if the rat pressed at intervals of 60-s or
greater, there would be one press per reinforcement.  On the same schedule,
however, if the rat pressed at a rate of several times per second, then
depending on the mix of intervals in the schedule, it might be possible for
the rat to produce dozens or even hundreds of lever-presses per pellet.  In
that case the matching law states that the rate of pressing on each lever
would be adjusted by the subject so as to produce an equal ratio of
lever-presses per pellet across the schedules, within the limits of
experimental error.

To answer one of Dick Robertson's questions, the data are reported for
individual subjects (they are not group averages), but do represent average
rates over the duration of a session.

Regards,

Bruce