**Orador :: **Prof Charles Johnson (The College of William and Mary, VA, USA)

**Título ::** Reciprocal Matrices and Ranking

**Data :: **3 de Outubro de 2023, 12h

**Local :: **

presencial: Sala de Seminários do DMAT

online: https://videoconf-colibri.zoom.us/j/93344876599?pwd=ejkrZ3FpYkh0NE1YV3NCdGFMOGw3QT09

**Resumo:: ** If $A=(a_{ij})$ is a positive matrix, it is called "reciprocal" if $a_{ji}=\frac{1}{a_{ij}}$, all $1\leq i,j,\leq n$. The entries are intended as pairwise, ratio comparisons among $n$ items. We mention several examples. The goal is to deduce a positive vector $w$ from $A$ to be used either ordinally or cardinally to rank the $n$ items. Such vector should be chosen from among "efficient" vectors, which will be defined. The efficient vectors will be discussed, as well as applications.