On d-orthogonality of the Sheffer systems associated to a convolution semigroup

  • Authors:
  • Célestin C. Kokonendji

  • Affiliations:
  • University of Pau, France and Laboratoire de Mathématiques Appliquées, CNRS FRE 2570-Département STID, Avenue de l'Université, 64000 Pau, France

  • Venue:
  • Journal of Computational and Applied Mathematics
  • Year:
  • 2005

Quantified Score

Hi-index 7.29

Visualization

Abstract

In this note we investigate which Sheffer polynomials can be associated to a convolution semigroup of probability measures, usually induced by a stochastic process with stationary and independent increments. From a recent kind of d-orthogonality (d ∈ {2,3....}), we characterize the associated d-orthogonal polynomials by the class of generating probability measures, which belongs to the natural exponential family with polynomial variance functions of exact degree 2d-1. This extends some results of (classical) orthogonality; in particular, some new sets of martingales are then pointed out. For each integer d ≥ 2 we completely illustrate polynomials with (2d-1)-term recurrence relation for the families of positive stable processes.