Departamento de Análise

Round-robin tournaments rank participants according to their results in all games, considering that all victories have the same value. However, our understanding is that victories against strong opponents have more value than those against weak opponents. Hence, such tournaments should consider this interpretation in their final rankings, using centrality measurements that evaluate the influence of an element based on its neighbours centralities. In this context, we use eigenvector and layer centralities to evaluate team performance in the 2014 Guanabara Cup, considering this understanding.

... and its Applications 423 (2007) 119 135 www.elsevier.com/locate/laa Walks and regular integral graphs Dragan Stevanovi ca, , Nair MM de Abreu b , Maria AA de Freitas b , Renata Del-Vecchio ca University of Ni , Serbia and Montenegro b Federal University of Rio de Janeiro ...

In this article, we construct graphs that are simultaneously integral, Laplacian integral and signless Laplacian integral. The graphs with this property, known in the literature, are regular or bipartite, unless by a few exceptions. We obtain infinite families of such graphs, that are neither regular nor bipartite, from join of regular graphs

ABSTRACT Let G be a simple graph and A=A(G), L=L(G) and Q=Q(G) the adjacency, the Laplacian and the signless Laplacian matrices of G, respectively. For each of the associated matrices of G, M=A, L, or Q, we call M-spectrum of G the spectrum of the matrix M. In this work we present the KK n j graphs, obtained from two copies of the complete graph K n by adding j edges, 1≤j≤n, between a vertex of one of the copies and j vertices of the other. We obtain M-spectral properties of this graph based on its clique number and its edge connectivity.

RESUMO A suavização da fronteira DEA foi proposta em 2002 para resolver o problema das múltiplas soluções ótimas para as DMUs extremo-eficientes na fronteira DEA clássica. Essa técnica substitui a fronteira original, linear por partes, por uma fronteira continuamente diferenciável, que passa pelas mesmas DMUs extremo-eficientes. Para escolher a fronteira que mais se aproxima da fronteira original, as funções objetivo dos diversos modelos de suavização existentes na literatura utilizam a topologia baseada no comprimento de arco (ou sua generalização multidimensional). Em 2014, foi proposto um modelo que utiliza outra função objetivo para a suavização da fronteira DEA, baseada na área (ou sua generalização multidimensional) das fronteiras. O presente trabalho estuda a topologia implicitamente utilizada nesse modelo, e também compara as características básicas das duas topologias da suavização. ABSTRACT Smooth DEA was first proposed in 2002 to solve the classic DEA problem of multiple optimal solutions for extreme-efficient DMUs. This technique replaces the original piecewise linear frontier by a new frontier with derivatives at all points that contains the same extreme-efficient DMUs. Most smooth models use the arc length based topology (or its multidimensional generalization) to determine the smooth frontier that is closest to the original DEA frontier. However, in 2014, the authors proposed a smooth model with a different objective function, based on the frontiersárea (or its multidimensional generalization). The present work studies the topology implicitly used in the new smooth model, and compares the basic characteristics from both topologies.

ABSTRACT According to the Brazilian Institute of Geography and Statistics, 40 million people worked in the black market in 2012. This result certainly represents an improvement on the informal employment calculated in 2001, but it is still extremely high by international standards. This article aims to contribute to this discussion by presenting the Siena Micro-Simulation Model (SM2) that is able to reproduce the Brazilian National Accounts System data, and to simulate, on a regional and national scale, the policies adopted to combat informal employment. SM2 has been widely used by EUROSTAT in other European countries, and enables not only conversion of gross to net income, but accounts for changes in the current tax rates and the implementation of the new tax burden. Based on the excellent results in terms of social insurance contributions, total taxes and disposable income, we can use the SM2 as a wide tool to simulate public policies in Brazil.