How to Predict Out of Range Output
- I have downloaded a trial version of EasyNN-plus and I am having a
hard time getting the type of response that I am looking for.
I am trying to use the NN to 'learn' a function based on observed
responses with the hope that I can then interrogate the NN to find a
region of the input space with expected good response.
Unfortunately, I cant find a way to have the NN predict an output
value outside the range of what it has already observed in the
training set. I assume this is due to the scaling that is employed,
but if I cant predict responses that are higher/lower that the
observed max/min in the training set it pretty much defeats my
Does anyone know a way around this? If I know where in the input
space to find min / max response I would interrogate that region for
the training set.
- On Tue, 01 Mar 2005 16:08:33 -0000, you wrote:
>Neural networks are useless at extrapolating. EasyNN-plus makes no
>Does anyone know a way around this? If I know where in the input
>space to find min / max response I would interrogate that region for
>the training set.
attempt to predict outputs outside the training range. Some other
applications try to extrapolate but are rarely successful.
There are some possibilities. The obvious one is to increase the
training range. This is sometimes possible using Tools > Extend
Learning... but can produce unexpected results. If the observed
responses can be ordered you may find that Action > Forecast... helps.
Steve Wolstenholme Neural Planner Software
EasyNN-plus. The easy way to build neural networks.