TY - JOUR PB - IEEE JF - IEEE Transactions on Information Theory IS - 1 SN - 0018-9448 N2 - A variational norm associated with sets of computational units and used in function approximation, learning from data, and infinite-dimensional optimization is investigated. For sets Gk obtained by varying a vector y of parameters in a fixed-structure computational unit K(-,y) (e.g., the set of Gaussians with free centers and widths), upper and lower bounds on the GK -variation norms of functions having certain integral representations are given, in terms of the £1-norms of the weighting functions in such representations. Families of functions for which the two norms are equal are described. ID - eprints1719 EP - 558 VL - 57 A1 - Gnecco, Giorgio A1 - Sanguineti, Marcello UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=5673958&isnumber=5673678 Y1 - 2011/// KW - ${cal L}_1$-norm KW - Approximation schemes KW - convex hulls KW - infinite-dimensional optimization KW - upper and lower bounds KW - variation with respect to a set AV - none SP - 549 TI - On a Variational Norm Tailored to Variable-Basis Approximation Schemes ER -