Abstract
We show that a large class of Bernstein-type operators usually considered in approximation theory diminish the total and the fine φ-variation, thus extending a classical result on 1-variation diminution concerning the Bernstein polynomials. Also, the closely related problem of approximation in φ-variation is thoroughly discussed. For these purposes, we use a probabilistic approach in which coupling methods play a fundamental role.
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Communicated by Vilmos Totik.
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Adell, J.A., de la Cal, J. Bernstein-type operators diminish the φ-variation. Constr. Approx 12, 489–507 (1996). https://doi.org/10.1007/BF02437505
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DOI: https://doi.org/10.1007/BF02437505