A Note on Selectors and Greedoids

This note deals with relations between selectors studied by Henry Crapo and a special class of greedoids introduced by these authors in a previous paper. We show that selectors are greedoids with the interval property and that a second property of Crapo, which he calls ‘locally free’ is the interval property without upper bound. In the last section of the paper we show that retract sequences of posets are general greedoids, but not selectors

Polymatroid greedoids

AbstractThis paper discusses polymatroid greedoids, a superclass of them, called local poset greedoids, and their relations to other subclasses of greedoids. Polymatroid greedoids combine in a certain sense the different relaxation concepts of matroids as polymatroids and as greedoids. Some characterization results are given especially for local poset greedoids via excluded minors. General construction principles for intersection of matroids and polymatroid greedoids with shelling structures are given. Furthermore, relations among many subclasses of greedoids which are known so far, are demonstrated

A note on selectors and greedoids

SIGLEPublished in Europ. J. Combinatorics (1985)6, 59-67 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

A note on selectors and greedoids

SIGLEDEGerman