Re: feedback

Anders Sandberg (asa@nada.kth.se)
22 Sep 1997 09:12:59 +0200


Damien Broderick <damien@ariel.ucs.unimelb.edu.au> writes:

> The term is regularly abused in the general English-speaking culture. New
> Age types, and many others, are always smiling gratefully when they receive
> what they call `positive feedback' (meaning, for them, encouragement or
> praise) and recoiling from the dreaded `negative reinforcement' (meaning,
> they suppose, disapproval). In fact, positive feedback is nothing more
> than returning a part of the system's output in such a way that the output
> *increases*, while negative feedback uses part of the system's current
> output to *restrict* or *lower* continuing output. (So, in a restricted
> sense, smiling at each other *is* `positive feedback', since it makes us
> feel good and improves our mood.)

To further elaborate (not to beat anybody over the head), feedback
and reinforcement are different things. While feedback is having the
output or results of a system affect the system back, reinforcement
is signals which teach the system. The classic form of negative reinforcement
is being given electric shocks when doing certain things: this will
make us less likely to do them (negative feedback would be that doing
these things causes us pain, with no need for external control).
Positive reinforcement is the opposite, we get rewarded for doing
certain things.

As a neuroscientist I'm constantly using these terms, so I thought it
might be a good idea to explain them. I have the feeling that too many
of us "experts" use terms on this list that few other readers understand.
Thus:

I HEREBY SWEAR THAT IF SOMEBODY ASKS ME WHAT I MEAN WITH A TERM I HAVE
USED IN A POSTING TO THIS LIST, I WILL TRY TO EXPLAIN IT AS CLEARLY AS
POSSIBLE.

-- 
-----------------------------------------------------------------------
Anders Sandberg                                      Towards Ascension!
asa@nada.kth.se                            http://www.nada.kth.se/~asa/
GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y