Labor staffing and scheduling models for controlling service levels

The problems of labor staffing and scheduling have received substantial attention in the literature. We introduce two new models of the labor staffing and scheduling problems that avoid the limitations of existing models. Collectively, the models have five important attributes. First, both models ensure the delivery of a minimally acceptable level of service in all periods. Second, one model can identify the least expensive way of delivering a specified aggregate level of customer service (the labor staffing problem and a form of labor scheduling problem). Third, the other model can identify the highest level of service attainable with a fixed amount of labor (the other form of the labor scheduling problem). Fourth, the models enable managers to identify the pareto relationship between labor costs and customer service. Fifth, the models allow a degree of control over service levels that is unattainable with existing models. Because of these attributes, which existing models largely do not possess, we expect these models to have broad applicability in a wide range of organizations operating in both competitive and noncompetitive environments. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 719–740, 1997     

Optimal inventory policies for substitutable commodities with stochastic demand

In this article we consider a stochastic model for two products which have a single-period inventory structure and which can be used as substitutes for each other should the need arise. Substitution will occur with probability one, but at perhaps a different revenue level. We prove that the expected profit function is concave, allowing us to find optimal stocking levels for the two products. We compare optimum inventory levels for the case of single substitution with that where there is no substitution. It is demonstrated for the case of single substitution that total optimum order quantities can actually increase or decrease with the substitution revenue.     

On compounded bivariate poisson distributions

A unified treatment is given for a class of discrete distributions derived by compounding a bivariate Poisson with a bivariate discrete or continuous distribution. Using generating functions a number of interesting results are obtained for probabilities, moments, cumulants, factorial moments, and factorial cumulants. Conditional distributions and regression functions are also examined. Five illustrative examples are presented in detail. © 1994 John Wiley & Sons, Inc.     

State fragility and violent uprisings in Nigeria

Abstract

The emergence of the Islamic sect, Boko Haram, and its transformation into a terrorist organisation has dominated recent discourse in the fields of political science and security studies, both within and without the socio-politico enclave known as Nigeria. Much of the discussion has centred on the extra-judicial execution of its founder, Mohammed Yusuf, which purportedly intensified the radicalisation of the group, and whether or not the sect receives operational and/or financial support from foreign terrorist associations. The interest of others has been to forecast the possibility of the internationalisation of the group's activities. This paper aligns with those whose interest is to identify and proffer ways of resolving factors that predisposed the Nigerian state to the levels of violence perpetrated by Boko Haram, with a view to averting much greater crises in the future. It adopts some historicism in demonstrating that the responsibility for the deepening insecurity in the country resides in the Nigerian state structure, which has often been seen as willing to sacrifice the well-being of the many for the benefit of a few. On the whole, the paper utilises state fragility as the framework of analysis by identifying the incapacity of the state in effective service delivery, which has as a result created a situation of mass unemployment and extreme poverty that has fanned the Boko Haram uprising. It concludes that a sustainable solution to the crisis lies in addressing the root causes of inequality, unemployment and poverty, with which most Nigerians, particularly in the north, subsist.     

EXAMINING ISRAEL'S NPT EXCEPTIONALITY: 1998–2005

Israel's exceptional status as a nonsignatory to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) has been an increasingly salient issue, particularly during the intense debate over universality in the 1995 NPT Review and Extension Conference, and again following the Indian and Pakistani tests in 1998. This analysis argues that despite these events, Israel's diplomatic position has not weakened significantly in the past decade. The factors that have led to this outcome include changes in the political and strategic environment, including the Iraqi and Iranian NPT violations, and Israeli engagement in different fora such as the Conference on Disarmament (CD) and the United Nations, and in bilateral strategic dialogues with key powers. This report examines whether Israel's exceptional status is likely to be maintained in the face of recent developments in Iran and the precedent set by the U.S.-India nuclear cooperation agreement.