Information-based complexity
Complexity and information
Constructing Randomly Shifted Lattice Rules in Weighted Sobolev Spaces
SIAM Journal on Numerical Analysis
Component-by-component construction of good lattice rules
Mathematics of Computation
Tractability of Approximation for Weighted Korobov Spaces on Classical and Quantum Computers
Foundations of Computational Mathematics
Multivariate L∞ approximation in the worst case setting over reproducing kernel Hilbert spaces
Journal of Approximation Theory
On the power of standard information for multivariate approximation in the worst case setting
Journal of Approximation Theory
On the approximation of smooth functions using generalized digital nets
Journal of Complexity
Interpolation lattices for hyperbolic cross trigonometric polynomials
Journal of Complexity
Multidimensional pseudo-spectral methods on lattice grids
Applied Numerical Mathematics
Journal of Approximation Theory
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We study multivariate approximation for continuous functions in the average case setting. The space of d variate continuous functions is equipped with the zero mean Gaussian measure whose covariance function is the reproducing kernel of a weighted Korobov space with the smoothness parameter @a1 and weights @c"d","j for j=1,2,...,d. The weight @c"d","j moderates the behavior of functions with respect to the jth variable, and small @c"d","j means that functions depend weakly on the jth variable. We study lattice rule algorithms which approximate the Fourier coefficients of a function based on function values at lattice sample points. The generating vector for these lattice points is constructed by the component-by-component algorithm, and it is tailored for the approximation problem. Our main interest is when d is large, and we study tractability and strong tractability of multivariate approximation. That is, we want to reduce the initial average case error by a factor @e by using a polynomial number of function values in @e^-^1 and d in the case of tractability, and only polynomial in @e^-^1 in the case of strong tractability. Necessary and sufficient conditions on tractability and strong tractability are obtained by applying known general tractability results for the class of arbitrary linear functionals and for the class of function values. Strong tractability holds for the two classes in the average case setting iff sup"d"="1@?"j"="1^d@c"d","j^s="1@?"j"="1^d@c"d","j^t/log(d+1)