A tighter formulation of the <Emphasis Type=Italic>p</Emphasis>-median problem

Given a set of clients and a set of potential sites for facilities, the p-median problem consists of opening a set of p sites and assigning each client to the closest open facility to it. It can be viewed as a variation of the uncapacitated facility location problem. We propose a new formulation of this problem by a mixed integer linear problem. We show that this formulation, while it has the same value by LP-relaxation, can be much more efficient than two previous formulations. The computational experiment performed on two sets of benchmark instances has showed that the efficiency of the standard branch-and-cut algorithm has been significantly improved. Finally, we explore the structure of the new formulation in order to derive reduction rules and to accelerate the LP-relaxation resolution.     

National Defense,Environmental Regulation,and Overhead Democracy: A View from the “Greening” of the U.S. Military

This study examines the patterns of politics accompanying efforts to hold the United States military accountable to U.S. environmental and natural resources (ENR) laws in the post-Cold War era. This analysis (1) uses three cases to describe what happened, and why, (2) to test several propositions related to military accountability to ENR laws in the post-Cold War era; (3) to offer a typology of tactics used that may help inform future research on intragovernmental regulation more generally; and (4) argues that public agencies have a responsibility to comply with the regulatory processes that hold them accountable to U.S. ENR laws.     

Country-specific institutional effects on ownership: concentration and performance of continental European firms

This paper examines the effect of country-specific institutional constructs on the relationship between ownership concentration and performance for firms in the eight Continental European countries of Austria, Belgium, Germany, Spain, France, Italy, the Netherlands and Portugal. Using data from publicly-traded firms owned by other companies (i.e., blocks), measures of the quality of investor and creditor protection and the effectiveness of legal institutions are applied. Employing a hierarchical moderated multiple regression analysis, differential validity is established for the relationship between ownership concentration and performance as measured by return on shareholders’ funds. This differential effect comes from creditor protection regimes and is consistent with a relational corporate governance model based on debt finance and concentrated ownership.     

When do Public Managers Imitate Each Other? Mimetic Decision Making in Contracting Decisions of Danish Municipalities

Using organizational new institutional theory, this paper explores a core mechanism underlying contracting decisions in public organizations. A central proposition of this branch of institutional theory is that uncertainty leads to organizational isomorphism. The present study investigates this proposition by asking: When does perceived uncertainty lead public managers to imitative behavior in contracting out decisions? Contrary to most previous studies, we apply an individual level approach and relate different types of perceived uncertainty of decision makers to mimetic decision making. We define mimetic decision making as when decision makers deliberately obtain information about other organizations in order to possibly imitate them. In a survey of Danish municipal managers facing important and complex contracting decisions, we test our hypotheses about three types of perceived uncertainty and mimetic decision making. The results show that technological uncertainty is strongly related to mimetic decision making among public managers. However, we do not find significant results for either volume uncertainty or performance uncertainty. The paper illustrates how uncertainty, through mimetic decision making, is connected to organizational isomorphism. It further highlights that future studies should pay attention to the multidimensionality of uncertainty and its consequences.     

Just-in-time scheduling with controllable processing times on parallel machines

We study scheduling problems with controllable processing times on parallel machines. Our objectives are to maximize the weighted number of jobs that are completed exactly at their due date and to minimize the total resource allocation cost. We consider four different models for treating the two criteria. We prove that three of these problems are NP\mathcal{NP} -hard even on a single machine, but somewhat surprisingly, the problem of maximizing an integrated objective function can be solved in polynomial time even for the general case of a fixed number of unrelated parallel machines. For the three NP\mathcal{NP} -hard versions of the problem, with a fixed number of machines and a discrete resource type, we provide a pseudo-polynomial time optimization algorithm, which is converted to a fully polynomial time approximation scheme.     

From Bureaucracy to Debureaucratization?

More than previous mild recessions, the current global crisis calls into question the merits of a model that held sway for almost three decades. Celebrated in the nineties in a “National Bestseller”, which even President Clinton considered to be a “blueprint” “for all officials to read”, the book—Reinventing Government—preached the reform of government in private sector ways. In stark contrast to Bureaucracy, which they considered “Bankrupt”. Authors Osborne and Gaebler (1993) promoted Debureaucratization, which they summed up as decentralization, deregulation, downsizing and outsourcing. It is time to revisit the assumptions of the Osborne-Gaebler model that has demonstrably failed. More than the model, however, the ways of its promotion in the market of ideas invites a word of caution. It prompted simplistic distortions, which typically followed from superficial analyses of Weber’s seminal opus (Timsit 2008:864–875). This paper reconsiders these two contrasting models, though not in “black” and “white”. Rather, the two are explored in dialectical terms, as outcomes of shifting ideologies, often taken to extremes.     

Median problems with positive and negative weights on cycles and cacti

This paper deals with facility location problems on graphs with positive and negative vertex weights. We consider two different objective functions: In the first one (MWD) vertices with positive weight are assigned to the closest facility, whereas vertices with negative weight are assigned to the farthest facility. In the second one (WMD) all the vertices are assigned to the nearest facility. For the MWD model it is shown that there exists a finite set of points in the graph which contains the locations of facilities in an optimal solution. Furthermore, algorithms for both models for the 2-median problem on a cycle are developed. The algorithm for the MWD model runs in linear time, whereas the algorithm for the WMD model has a time complexity of  O(n²)\mathcal{O}(n^{2}) .     

Federalism and the Implementation of Environmental Policy: Changing Trends in Canada and the United States

In a federal system of government, powers are shared by the national and sub-national units in accordance with the provisions of the Constitution. However, the process of policy implementation may differ on the basis of allocation of power and the nature of the system. Canada and the United States of America adopted federal systems of government, and faced similar pressures for implementing policies on environmental issues. Yet, the degree of success and outcome appear to be different due to variations in the strength of the respective federalist systems. An analysis of the various aspects of the federal system in the two countries reveals noticeable differences in institutional configurations, relationship between national and sub-national units, and variances in intra-institutional relations. All these have contributed to a divergence in the past, but there is an emerging trend of convergence as both the Canadian and American governments are gradually moving away from their existing patterns of policy implementation toward a new approach involving private-sector initiatives and self-enforcement with strong inclinations toward voluntarization, corporatization and marketization.     

The impact of institutional changes on corporate governance mechanisms in transition economies

We examine how institutional changes affect corporate governance in transition economies. We develop a transition model that specifies three stages of the transition process including the early, intermediate, and late. We develop a framework for assessing the effectiveness of widely recognized corporate governance mechanisms (CGMs) in and across these stages. Our general proposition is that as transition economies move from early, to intermediate, to late stages, effective CGMs tend to be those that are based on state administrative control power, social networks and private orders, and market forces and formal institutions, respectively. Our study has contributions and implications regarding the transition economies and the impacts of institutions on corporate governance.