How to choose "Nlocmin,Nlocmax" in non linear regression and curve fitting?
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How can one choose "Nlocmin and Nlocmax" values for non linear regression using ANN feedforwardnet in the code mentioned by Greg sir??
Link to the thread
2. Estimate, by trial and error, the minimum number of hidden nodes necessary for successfully approximating the underlying input-output transformation. For a smooth function with Nlocmin local minima and Nlocmax local maxima, a reasonable lower
bound is H >= 2*max(Nlocmin,Nlocmax). Sometimes it is prudent to count endpoint extrema as 1/2 a local extremum. The addition of real-world noise, interference and measurement error should not change that minimum number. However, the contamination may make it difficult to identify the significant error-free extrema.
Greg Heath on 28 Mar 2015
Edited: Greg Heath on 28 Mar 2015
Plot the target and count the number of local extrema.
This will only work for relatively smooth functions.
Otherwise use the search over
Hmin:dH:Hmax < Hub
with a preference for Hmax << Hub
For details, search NEWSGROUP and ANSWERS using
Hope this helps
Thank you for formally accepting my answer