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341.
    
The issue of guns or butter is one of the most fundamental economic questions, yet there is no consensus on a theoretical framework for examining it. Over the last decade, a version of a simple Keynesian macroeconomic model has been applied a number of times to examining the link between defence spending and economic growth in a range of countries. There are reasons for doubting the soundness of this model as a basis for empirical work.  相似文献   
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We review some critical comments upon our earlier paper in this journal and respond to these. We also critically evaluate a proposed alternative methodology giving reasons why our own provides a more robust approach for examining the nexus between military spending and economic growth in South Asia.  相似文献   
344.
    
Economic reconstruction typically takes place after the end of war. Yet recently, economic reconstruction has been viewed as a means to ‘win hearts and minds’ during ongoing conflict. Drawing on a variety of reconstruction experiences from Afghanistan and Iraq, we identify four ‘reconstruction traps’ that result from the incentives and constraints faced by actors involved in economic reconstruction during ongoing conflict. These traps include: 1. the credible commitment trap, 2. the knowledge trap, 3. the political economy trap, and 4. the bureaucracy trap. Avoiding these traps is critical for successful economic reconstruction; and we discuss potential strategies for doing so.  相似文献   
345.
In 2004, stretched by wartime deployments, the US Army countered declining retention by increasing re‐enlistment bonuses and implementing stop‐loss to prevent soldiers from separating at the end of their enlistment. We estimate the effects of bonuses, deployment, and stop‐loss on re‐enlistment between FY 2002 and 2006. We estimate that the baseline propensity to re‐enlist fell by 20%. However, we find that deployed soldiers are more likely to re‐enlist and that the estimated effects of re‐enlistment bonuses are similar to those estimated in peacetime. We evaluate the reasons for our findings, and calculate the cost effectiveness of re‐enlistment bonuses.  相似文献   
346.
    
We investigate the problem in which an agent has to find an object that moves between two locations according to a discrete Markov process (Pollock, Operat Res 18 (1970) 883–903). At every period, the agent has three options: searching left, searching right, and waiting. We assume that waiting is costless whereas searching is costly. Moreover, when the agent searches the location that contains the object, he finds it with probability 1 (i.e. there is no overlooking). Waiting can be useful because it could induce a more favorable probability distribution over the two locations next period. We find an essentially unique (nearly) optimal strategy, and prove that it is characterized by two thresholds (as conjectured by Weber, J Appl Probab 23 (1986) 708–717). We show, moreover, that it can never be optimal to search the location with the lower probability of containing the object. The latter result is far from obvious and is in clear contrast with the example in Ross (1983) for the model without waiting. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009  相似文献   
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Suppose that failure times are available from a random sample of N systems of a given, fixed design with components which have i.i.d. lifetimes distributed according to a common distribution F. The inverse problem of estimating F from data on observed system lifetimes is considered. Using the known relationship between the system and component lifetime distributions via signature and domination theory, the nonparametric maximum likelihood estimator N(t) of the component survival function (t) is identified and shown to be accessible numerically in any application of interest. The asymptotic distribution of N(t) is also identified, facilitating the construction of approximate confidence intervals for (t) for N sufficiently large. Simulation results for samples of size N = 50 and N = 100 for a collection of five parametric lifetime models demonstrate the utility of the recommended estimator. Possible extensions beyond the i.i.d. framework are discussed in the concluding section. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
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We consider the single machine parallel batch scheduling problems to minimize makespan and total completion time, respectively, under precedence relations. The complexities of these two problems are reported as open in the literature. In this paper, we settle these open questions by showing that both problems are strongly NP‐hard, even when the precedence relations are chains. When the processing times of jobs are directly agreeable or inversely agreeable with the precedence relations, there is an O(n2) time algorithm to minimize the makespan. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004  相似文献   
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ABSTRACT

The debate concerning the Nigerian terrorist Boko Haram is typically simplified across two false dichotomies. First, it is treated as either a local conflict in northeast Nigeria with its epicentre in Borno State or part of a broader conflict in Northwest Africa (and beyond), encompassing northern Cameroon, southern Chad, Niger, and reaching into Libya and Mali. The second dichotomy concerns whether it is animated by local material conditions on the ground, or is part of a broader anti-West jihad. The Boko Haram insurgency is not that simple. It is, rather, a multidimensional conflict and can change overtime.  相似文献   
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