# Function Approximation With XCS: Hyperellipsoidal Conditions, Recursive Least Squares, and Compaction

@article{Butz2008FunctionAW, title={Function Approximation With XCS: Hyperellipsoidal Conditions, Recursive Least Squares, and Compaction}, author={Martin Volker Butz and Pier Luca Lanzi and Stewart W. Wilson}, journal={IEEE Transactions on Evolutionary Computation}, year={2008}, volume={12}, pages={355-376} }

An important strength of learning classifier systems (LCSs) lies in the combination of genetic optimization techniques with gradient-based approximation techniques. The chosen approximation technique develops locally optimal approximations, such as accurate classification estimates, Q-value predictions, or linear function approximations. The genetic optimization technique is designed to distribute these local approximations efficiently over the problem space. Together, the two components…

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