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A Genetic Programming-Driven 6 b$ W0 b+ L# W* D
Data Fitting Method
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/ s2 `0 [& M" U6 mData fifitting is the process of constructing a curve, or a set of mathematical functions, that has) i4 Z# M3 M. |0 E! o; F0 B2 o% L
the best fifit to a series of data points. Different with constructing a fifitting model from same type of function,3 ]- N* c9 p2 z+ a7 [
such as the polynomial model, we notice that a hybrid fifitting model with multiple types of function may have# T6 I3 J( ~2 l1 Y$ L `
a better fifitting result. Moreover, this also shows better interpretability. However, a perfect smooth hybrid
* d! b$ h x- V, lfifitting model depends on a reasonable combination of multiple functions and a set of effective parameters.9 q& M( u: c7 F0 e: b5 R
That is a high-dimensional multi-objective optimization problem. This paper proposes a novel data fifitting! W) P( T N2 o$ C
model construction approach. In this approach, the model is expressed by an improved tree coding expression3 u. ]$ \1 m+ R* r
and constructed through an evolution search process driven by the genetic programming. In order to verify7 Q# }4 V9 S, U$ }8 U8 Y
the validity of generated hybrid fifitting model, 6 prediction problems are chosen for experiment studies. The s% i4 P$ q7 O b" R9 s
experimental results show that the proposed method is superior to 7 typical methods in terms of the prediction5 m5 \+ j) ~: y/ E) K) ~2 f' [
accuracy and interpretability
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