Least-absolute-value estimators for one-way and two-way tables

This paper concerns itself with the problem of estimating the parameters of one-way and two-way classification models by minimization of the sum of the absolute deviations of the regression function from the observed points. The one-way model reduces to obtaining a set of medians from which optimal parameters can be obtained by simple arithmetic manipulations. The two-way model is transformed into a specially structured linear programming problem, and two algorithms are presented to solve this problem. The occurrence of alternative optimal solutions in both models is discussed, and numerical examples are presented.     

A note on the limitations of goal programming as observed in resource allocation for marine environmental protection

After first formulating the problem of the Marine Environmental Protection program of the Coast Guard as a multiple-objective linear program, we investigate the applicability and limitations of goal programming. We point out how the preemptive goal-programming approach is incompatible with utility preferences. Then we observe the tendency of optimal solutions for standard linear goal programs to occur at extreme points. We also note problems of more general approaches, such as dealing with additively separable approximations to preferences.     

From the sea to outer space: The command of space as the foundation of spacepower theory

Colin Gray once lamented the absence of a ‘Mahan for the final frontier’ and spacepower theory in strategic studies. This article proposes the command of space as the fundamental concept of spacepower theory, and that Mahan himself has much to offer in the endeavour of spacepower theory-making than has hitherto been realised. The theory is advanced by tempering versions of the ‘command of space’, stressing its educational intent, and explaining the nuanced sub-concepts of space control and denial through understanding some precedents set by seapower theory. In the process, aspects of Mahanian and Corbettian seapower theory are unified.     

The United States and Latin America: Shaping an elusive future

This article presents a regional overview of US‐Latin American security relations, focusing on those countries where US national security interests are most likely to be endangered over the next two decades. The author examines the current US strategy of ‘shaping’ the Latin security environment, with a view to assessing the strength and weaknesses of this approach. The article presents some policy recommendations, including the recommendation that the US do more to redress the historical imbalance in Latin American civil‐military relations by strengthening civilian institutions. It also argues that at the regional level a major effort be made to recapture momentum toward the creation of a Free Trade Association of the Americas.     

Dynamic service rate control for a single‐server queue with Markov‐modulated arrivals

We consider the problem of service rate control of a single‐server queueing system with a finite‐state Markov‐modulated Poisson arrival process. We show that the optimal service rate is nondecreasing in the number of customers in the system; higher congestion levels warrant higher service rates. On the contrary, however, we show that the optimal service rate is not necessarily monotone in the current arrival rate. If the modulating process satisfies a stochastic monotonicity property, the monotonicity is recovered. We examine several heuristics and show where heuristics are reasonable substitutes for the optimal control. None of the heuristics perform well in all the regimes and the fluctuation rate of the modulating process plays an important role in deciding the right heuristic. Second, we discuss when the Markov‐modulated Poisson process with service rate control can act as a heuristic itself to approximate the control of a system with a periodic nonhomogeneous Poisson arrival process. Not only is the current model of interest in the control of Internet or mobile networks with bursty traffic, but it is also useful in providing a tractable alternative for the control of service centers with nonstationary arrival rates. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 661–677, 2013     

‘Today we shall drink blood’: internal unrest in Nigeria

Despite some tentative internal peace agreements, Nigeria continues to face violence from multiple groups. This violence feeds upon itself, with segments of the population being mobilized both for self defense and for pressing their ideological and practical goals. These multiple sources of violence, which the Nigerian government appears unable to control to any significant degree, have a long term corrosive effect on the country's internal stability. There are few reasons to be sanguine as to any rapid changes to the level of overall violence or the relative number of armed groups, although their specific identities may shift. Nigeria represents a good case study of a country in which relatively low but persistent violence by a multiplicity of groups can have major impacts on internal security.     

Capacity and competence: full-spectrum counterinsurgency in the Horn of Africa

From 2006 to 2011, al Qaeda's East African proxy, al Shabaab, served as de facto ruling party of Somalia despite the efforts of the internationally recognized Transitional Federal Government (TFG). During these five years, a violent struggle between al Shabaab and the Burundian and Ugandan Peacekeepers of the African Union Mission in Somalia (AMISOM) resulted in thousands of dead civilians, hundreds of thousands of internally displaced persons, and a strategic environment inhospitable to reconciliation, recovery, or development. Beginning in August 2011, AMISOM was able to break the deadlock and force al Shabaab from Mogadishu, then subsequently, Kismayo, and ultimately to consolidate and reorganize in the Somali hinterland. In order to continue the momentum, the African Union and other partner nations must support the newly recognized Somali Federal Government (SFG), neutralize al Shabaab, and provide good governance to its constituents. Al Shabaab's revenue streams must be shut down and their offensive capability must be degraded while the strategic environment is shaped to ensure that conditions conducive to a revival do not exist. Failure to do so will likely see Somalia continuing to produce Islamic extremists and pirates to menace international maritime traffic in the Western Indian Ocean, destabilize East Africa, and adversely impact millions.     

BOOK REVIEWS

This study examines how young people who have joined the South African National Defence Force (SANDF) on the two-year Military Skills Development System (MSDS) contract experience military service, and the effect this has on their ability to readapt to civilian life. The first part of the study examines the theoretical debates associated with military socialisation and reintegration into civilian life. Hereafter, the findings are presented in terms of the experiences of MSDS privates serving in the infantry, those that have left, and the perceptions of employment agencies in terms of the marketability of military skills. The conclusion is reached that MSDS members experience their two years in the SANDF as life-changing, that this affects their ability to reintegrate back into civilian society, and that the skills acquired during military training is of limited market value. The conclusion is reached that more needs to be done to assist these young military veterans to adapt to civilian life and to augment their military experience with more marketable skills to enable them to find gainful employment.