In this paper, we adopt various greedy result diversification strategies to the problem of feature selection for learning to rank. Our experimental evaluations using several standard datasets reveal that such diversification methods are quite effective in identifying the feature subsets in comparison to the baselines from the literature.

Dominance hierarchies are group-level properties that emerge from the aggression of individuals. Although individuals can gain critical benefits from their position in a hierarchy, we do not understand how real-world hierarchies form. Nor do we understand what signals and decision-rules individuals use to construct and maintain hierarchies in the absence of simple cues such as size or spatial l...

The lattice of flats of a matroid or combinatorial geometry can be regarded as a sublattice (with rank function) of the lattice of subsets of a set, having the property that, given an element of rank r of the lattice and a point outside it, a unique element of rank r+1 covers both. This paper develops a theory of permutation geometries, which are similarly defined objects in the semilattice of ...

Let R be a commutative ring with identity and Mbe a unitary R-module. In this paper we generalize the conceptmultiplicatively closed subset of R and we study some propertiesof these genaralized subsets of M. Among the many results in thispaper, we generalize some well-known theorems about multiplicativelyclosed subsets of R to these generalized subsets of M. Alsowe show that some other well-kno...

Generalized splines on a graph [Formula: see text] with edge labels in commutative ring are vertex labelings such that if two vertices share an text], the difference between lies ideal generated by label. When is integral domain, set of all finitely text]-module rank number text]. We find determinantal conditions subsets determine whether free module, and so, so-called “flow-up class basis” exi...

background: lymphocyte subsets enumeration is considered prominent in the management of primary and acquired immunodeficiency disorders. because of local variations due to race, age, gender, and environmental conditions on lymphocyte subsets, and to improve the accuracy of interpretation of laboratory findings, reference intervals must be determined in every population. objective: to establish ...

Blocks of a matroid are called hyperplanes. For various definitions and results connected with matroids, see [26]. Subsets of X , which are intersections of hyperplanes are called flats of a matroid. Each subset Y c_ X has a well-defined rank. If F is a flat of rank i and x e X \ F , then, there is a unique flat of rank (i + 1) which contains FU{x}. Rank of X is said to be the rank of matroid. ...

Abstract In this paper we study the existence of higher dimensional arithmetic progressions in Meyer sets. We show that case when ratios are linearly dependent over ${\mathbb Z}$ is trivial and focus on for which independent. Given a set $\Lambda $ fully Euclidean model with property finitely many translates cover , prove can find arbitrary length k independent if only at most rank -module gene...