Scientia Sinica Mathematica
Complexity of Sobolev imbeddings and integration in the deterministic and randomized settings
Peixin Ye
Abstract
This paper reformulates the problems of approximation of imbedding and integration from anisotropic Sobolev classes B(Wrp([0, 1]d)) in the deterministic, randomized and average case settings, and obtains the exact orders of the n-th minimal error of these problems in all three settings. The results show that in the case of B(Wrp([0, 1]d)) being not imbedded into the space of continuous functions C([0, 1]d), the randomized and average case error are essential smaller than the deterministic ones. Quantitatively, this maximal gain for imbedding problem amounts to the factor n-1+ε for any ε > 0, and for integration problem the gain is up to factor n-1 which is also the maximal speedup over the deterministic algorithms observed so far in natural numerical problems.