文摘
We prove lower bounds for the approximation error of the variation-diminishing Schoenberg operator on the interval pan id="mmlsi1" class="mathmlsrc">pan class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0885064X15000813&_mathId=si1.gif&_user=111111111&_pii=S0885064X15000813&_rdoc=1&_issn=0885064X&md5=179ecf511fd06a3767d0870b242ab09c" title="Click to view the MathML source">[0,1]pan>pan class="mathContainer hidden">pan class="mathCode">pan>pan>pan> in terms of classical moduli of smoothness depending on the degree of the spline basis. For this purpose we use a functional analysis framework in order to characterize the spectrum of the Schoenberg operator and investigate the asymptotic behavior of its iterates.