In this paper, we propose an oligopolistic model of electricity market of Mexico and analyze numerical experiments based upon this model. Presently, the Mexican electricity market is presented by the state-regulated monopoly, so a competition market is not yet established. Our work can be evaluated as an empirical study of possible liberalization effects for Mexico. An oligopolistic market stru...

Many researchers show that “market institutions” are an ideal means to exchange and allocate resources under the assumptions of perfect and symmetric information and perfect competition. However, in the real world, we observe many instances in which these assumptions are not satisfied due to imperfect competition, incomplete information, transaction costs, and externalities. In this study we fo...

This paper studies the effect of differences in the rate of technological progress between sectors on the relative sizes of those sectors in terms of revenues. There are two sectors: a stagnant sector, where productivity does not change over time, and a progressive sector, where costs decrease over time due to exogenous technological progress. We consider a conjectural variation approach to com...

The complement of a graph G is denoted by G. χ(G) denotes the chromatic number and ω(G) the clique number of G. The cycles of odd length at least five are called odd holes and the complements of odd holes are called odd anti-holes. A graph G is called perfect if, for each induced subgraph G of G, χ(G) = ω(G). Classical examples of perfect graphs consist of bipartite graphs, chordal graphs and c...

The Strong Perfect Graph Conjecture (SPGC) was certainly one of the most challenging conjectures in graph theory. During more than four decades, numerous attempts were made to solve it, by combinatorial methods, by linear algebraic methods, or by polyhedral methods. The rst of these three approaches yielded the rst (and to date only) proof of the SPGC; the other two remain promising to consider...

The pre-coloring extension problem consists, given a graph G and a subset of nodes to which some colors are already assigned, in finding a coloring of G with the minimum number of colors which respects the pre-coloring assignment. This can be reduced to the usual coloring problem on a certain contracted graph. We prove that pre-coloring extension is polynomial for complements of Meyniel graphs....

The construction of joins and secant varieties is studied in the combinatorial context of monomial ideals. For ideals generated by quadratic monomials, the generators of the secant ideals are obstructions to graph colorings, and this leads to a commutative algebra version of the Strong Perfect Graph Theorem. Given any projective variety and any term order, we explore whether the initial ideal o...

The pre-coloring extension problem consists, given a graph G and a subset of nodes to which some colors are already assigned, in nding a coloring of G with the minimum number of colors which respects the pre-coloring assignment. This can be reduced to the usual coloring problem on a certain contracted graph. We prove that pre-coloring extension is polynomial for complements of Meyniel graphs. W...

Abstract This paper establishes relationships between static Nash equilibria and dynamic Markov perfect equilibria of tariff and quota retaliation games. In supermodular games where tariffs are strategic complements, the steady state of every, symmetric Markov perfect equilibrium must have lower tariffs than in the static equilibrium. If tariffs are strategic substitutes, tariffs in the dynamic...

Spatial pattern of trees can possibly indicate stand history, population dynamics, and species competition. This research was investigated in the Chahartagh forest reserve, Ardal region, chaharmehal and Bakhtiari Province, Central Zagros forest, and southwest Iranian state. In this study 53 hectare of the study area was selected and perfect inventory.  Information includes the position and kind...