Abstract: This paper estimates upper and lower bounds for the approximation rates of iterated Boolean sums of multivariate Bernstein polynomials. Both direct and inverse inequalities for the approximation rate are established in terms of a certain -functional. From these estimates, one can also determine the class of functions yielding optimal approximations to the iterated Boolean sums. [Copyright &y& Elsevier]
Abstract: In the present paper, we investigate the convergence and the approximation order of the localized Szsz–Mirakjan operators, and obtain some new results to improve the results due to Omey [Note on operators of Szsz–Mirakjan type, J. Approx. Theory 47 (1986) 246–254]. [Copyright &y& Elsevier]