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On the Improved Rates of Convergence for Matern-type Kernel Ridge Regression, with Application to Calibration of Computer Models

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 Added by Yan Wang
 Publication date 2020
and research's language is English




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Kernel ridge regression is an important nonparametric method for estimating smooth functions. We introduce a new set of conditions, under which the actual rates of convergence of the kernel ridge regression estimator under both the L_2 norm and the norm of the reproducing kernel Hilbert space exceed the standard minimax rates. An application of this theory leads to a new understanding of the Kennedy-OHagan approach for calibrating model parameters of computer simulation. We prove that, under certain conditions, the Kennedy-OHagan calibration estimator with a known covariance function converges to the minimizer of the norm of the residual function in the reproducing kernel Hilbert space.



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