>> How about smoothing the percentages, and then take the second
>> derrivative to find the inflection point?
> This solution is what I've been using so far. The only difference is that
I am smoothing the 1st derivative, since its
> the one I want to be smooth, smoothing the percentages curve does not
produce good results.
I've noticed something:
What I am using is something like:
"The fist value where the 2nd derivative changes its sign" To find the f''(x)=0
But you have suggested the max value of the 2nd derivative.
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