[From Rick Marken (941104.1400)]
Bruce "the animist" Abbott (941104.1500 EST) --
The aliens have completed their work on ECOLI4, and have asked me to transmit
it to Enterprise.
Tell the aliens that ECOLI4 still contains no reinforcement. The stimulus
effects just go back one extra trial. That is, the change in response
probability depends on the current input (dNut) and the prior input
(NutSave) but there is no differential change in the probability of the
response depending on what response was actually made after the prior
stimulus - - ie. there is no reinforcement. Because there is no
reinforcement, E. coli still does its biased random walk to the target; that
is, it controls.
Show the aliens my post (941103.2100) and tell them that they will have a
reinforcement model if they implement the method of updating
pTumbleGivenSplus and pTumbleGivenSminus (I didn't notice the "p"'s before)
that I described in that post. [Hint: in order to do this, the program will
have to keep track, not only of the prior stimulus, but of the response to
that stimulus].
Tell the aliens that they'll know that they've got the reinforcement
model right when E. coli just does a random walk around the screen, sometimes
getting to the target by chance but usually not.
May the force be with you.
Oops. Wrong movie.
Best
Leonard