Clustering on antimatroids and convex geometries
نویسندگان
چکیده
The clustering problem as a problem of set function optimization with constraints is considered. The behavior of quasi-concave functions on antimatroids and on convex geometries is investigated. The duality of these two set function optimizations is proved. The greedy type Chain algorithm, which allows to find an optimal cluster, both as the most distant group on antimatroids and as a dense cluster on convex geometries, is described. Key-Words: Quasi-concave function, antimatroid, convex geometry, cluster, greedy algorithm
منابع مشابه
Several Aspects of Antimatroids and Convex Geometries Master's Thesis
Convexity is important in several elds, and we have some theories on it. In this thesis, we discuss a kind of combinatorial convexity, in particular, antimatroids and convex geometries. An antimatroid is a combinatorial abstraction of convexity. It has some di erent origins; by Dilworth in lattice theory, by Edelman and Jamison in the notions of convexity, by Korte{Lov asz who were motivated by...
متن کاملMathematical Morphology and Poset Geometry
The aim of this paper is to characterize morphological convex geometries (resp., antimatroids). We define these two structures by using closure operators, and kernel operators. We show that these convex geometries are equivalent to poset geometries. 2000 Mathematics Subject Classification. 37F20, 06A07.
متن کاملA greedy algorithm for convex geometries
Convex geometries are closure spaces which satisfy anti-exchange property, and they are known as dual of antimatroids. We consider functions defined on the sets of the extreme points of a convex geometry. Faigle– Kern (1996) presented a greedy algorithm to linear programming problems for shellings of posets, and Krüger (2000) introduced b-submodular functions and proved that Faigle–Kern’s algor...
متن کاملQuasi-concave functions on antimatroids
In this paper we consider quasi-concave set functions defined on antimatroids. There are many equivalent axiomatizations of antimatroids, that may be separated into two categories: antimatroids defined as set systems and antimatroids defined as languages. An algorthmic characterization of antimatroids, that considers them as set systems, was given in [4]. This characterization is based on the i...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2003