Does leaving a currency union reduce international trade? We answer this question using a large annual panel data set covering 217 countries from 1948 through 1997. During this sample a large number of countries left currency unions; they experienced economically and statistically significant declines in bilateral trade, after accounting for other factors. Assuming symmetry, we estimate that a ...

Abstract This paper describes the incorporation of uncertainty in diagnostic reasoning based on the set covering model of Reggia et. al. extended to what in the Artificial Intelligence dichotomy between deep and compiled (shallow, surface) knowledge based diagnosis may be viewed as the generic form at the compiled end of the spectrum. A major undercurrent in this is advocating the need for a st...

A set of points and a positive integer m are given and our goal is to cover the maximum number of these point with m disks. We devise the first output sensitive algorithm for this problem. We introduce a parameter ρ as the maximum number of points that one disk can cover. In this paper first we solve the problem for m = 2 in O(nρ + ρ log ρ)) time. The previous algorithm for this problem runs in...

We consider a problem of minimizing the number of batches of a fixed capacity processing the orders of various sizes on a finite set of items. This batch consolidation problem is motivated by the production system typical in raw material industries in which multiple items can be processed in the same batch if they share sufficiently close production parameters. If the number of items processed ...

This paper examines the consequences of using “real-time” data for business cycle analysis in Germany based on a novel data set covering quarterly real output data from 1968 to 2001. Real-time output gaps are calculated. They differ considerably from their counterparts based on the most recent data. Moreover, they are not rational forecasts of the final series. The consequences of using real-ti...

Set multi-covering is a generalization of the set covering problem where each element may need to be covered more than once and thus some subset in the given family of subsets may be picked several times for minimizing the number of sets to satisfy the coverage requirement. In this paper, we propose a family of exact algorithms for the set multi-covering problem based on the inclusionexclusion ...

The Set Covering Problem is a classic combinatorial problem which is looking for solutions to cover needs on a geographic area. In this paper, we applied new ideas to solve The Set Covering Problem. Intelligent Water Drop is a nature inspired algorithm based on water drops behavior on natural river systems and the events that change the nature of water drop and the river environment. It observe...

Aguilera et al. [DiscreteAppl.Math. 121 (2002) 1–13] give a generalization of a theorem of Lehman through an extension P̄j of the disjunctive procedure defined by Balas, Ceria and Cornuéjols. This generalization can be formulated as (A) For every clutter C, the disjunctive index of its set covering polyhedron Q(C) coincides with the disjunctive index of the set covering polyhedron of its blocker...

In this note, we present a simple combinatorial factor 8 algorithm for approximating the minimum hitting set of a family R = {R1, . . . ,Rn} of axis-parallel rectangles in the plane such that there exists an axis-monotone curve γ separating the same two opposite corners of each rectangle Ri (say, the lower left and upper right corners).

We prove a downward separation for Σ2-time classes. Specifically, we prove that if Σ2E does not have polynomial size non-deterministic circuits, then Σ2SubEXP does not have fixed polynomial size nondeterministic circuits. To achieve this result, we use Santhanam’s technique [16] on augmented Arthur-Merlin protocols defined by Aydinlioğlu and van Melkebeek [1]. We show that augmented ArthurMerli...