Let Fi h(k, n) be the ith ordered configuration space of all distinct points H1, . . . ,Hh in the Grassmannian Gr(k, n) of k-dimensional sub- spaces of Cn, whose sum is a subspace of dimension i. We prove that Fi h(k, n) is (when non empty) a complex submanifold of Gr(k, n)h of dimension i(n -...

A toric arrangement is a finite set of hypersurfaces in a complex torus, every hypersurface being the kernel of a character. In the present paper we prove that if TfW is the toric arrangement defined by the cocharacters lattice of a Weyl group fW, then the integer cohomology of its complement is...

Here the reader can find some basic definitions and notations in order to better understand the model for social choise described by L. Marengo and S. Settepanella in their paper: Social choice among complex objects. The interested reader can refer to [Bou68], [Massey] and [OT92] to go into more...

In this article we propose a new methodology for computing the aggregate productivity of an industry, its variations and decompositions of the latter into changes of individual productivities (within effect) and changes in industry composition (between effect). Current aggregate measures rely on...

The paper presents a new framework to assess firm level heterogeneity and to study the rate and direction of technical change. Building on the analysis of revealed short-run production functions by Hildenbrand (1981), we propose the (normalized) volume of the zonotope composed by vectors-firms...