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471.
472.
We introduce an optimal stopping problem for selling an asset when the fixed but unknown distribution of successive offers is from one of n possible distributions. The initial probabilities as to which is the true distribution are given and updated in a Bayesian manner as the successive offers are observed. After receiving an offer, the seller has to decide whether to accept the offer or continue to observe the next offer. Each time an offer is observed a fixed cost is incurred. We consider both the cases where recalling a past offer is allowed and where it is not allowed. For each case, a dynamic programming model and some heuristic policies are presented. Using simulation, the performances of the heuristic methods are evaluated and upper bounds on the optimal expected return are obtained. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
473.
474.
Many authors contend that ethnic extremism coupled with political manipulation were the primary factors behind the Rwandan genocide. Yet, to oversimplify the cause of this tragedy makes one blind to the complicated nexus that generated the outcome. Even though this genocide was quick in its execution, the events that lead to this massacre took years to unfold. We argue that the evolution of human capital and the competition for scarce resources contributed to the genocide. 相似文献
475.
Sean M. Maloney 《Small Wars & Insurgencies》2013,24(1):27-44
Analytical focus on military operations in Iraq continue to overshadow analysis of the war in Afghanistan as it enters its sixth year. It is now possible to discern several clearly-delineated periods of coalition counterinsurgency and stabilization operations. What is the nature of the war and how has it evolved? Has there been success so far in Afghanistan? 相似文献
476.
Dennis M. Rempe 《Small Wars & Insurgencies》2013,24(3):24-61
In October 1959 the Eisenhower administration dispatched a CIA Special Team to survey the violence problem in Colombia. This article, part one of a two‐part series, examines this first significant attempt by a US administration to influence that nation's internal security situation. It investigates the Special Team's actions and analyses its recommendations for transforming Colombia's conventionally‐orientated security forces. The Team's survey, which focuses on counter‐insurgency tactics, civil action, intelligence operations, psychological warfare, and covert action, is the foundation from which Colombia's modern internal security structures are derived. 相似文献
477.
Christopher M. Faulkner Joshua E. Lambert Jonathan M. Powell 《Small Wars & Insurgencies》2013,24(3):641-659
ABSTRACTThis paper challenges recent claims that competitive market dynamics incentivize Private Military and Security Companies (PMSCs) to fully commit to providing effective services, thereby reducing the duration of civil war. Our assessment of a most-likely case scenario for this argument – Sierra Leone – reveals four critical problems. First, there is rarely direct competition, even if numerous companies are present. Second, the presence of multiple PMSCs usually represents a collaboration among subsidiaries providing distinct services, often under the same corporate umbrella. Third, data aggregation obfuscates the overlap of PMSC presence, inflating the amount of perceived competition. Finally, we raise concerns regarding how quantitative analyses can conflate conflict intensity with conflict termination. 相似文献
478.
A. S. Andreou ? K. E. Parsopoulos ? M. N. Vrahatis § G. A. Zombanakis 《Defence and Peace Economics》2013,24(5):481-495
The issue that this paper tackles is the assessment of the relative security benefits that Cyprus and Greece derive in the context of their cooperation on defence matters. This form of cooperation, known as the ‘Integrated Defence Space Doctrine’, aims at defending their interests in the Aegean Sea and the broader East Mediterranean theatre. The paper relies heavily on earlier research on this topic, which deals with the Greek–Cypriot alliance facing an arms race against Turkey, and uses a coefficient especially designed to assess the optimal levels of security and the associated defence expenditure of the two allies. A comparison of the relative security coefficient values for the two allies suggests that the security benefit that Greece derives thanks to its alliance with Cyprus exceeds the corresponding Cypriot benefit by far. Given the importance assigned to human resources by this index, in conjunction with the demographic problems of Greece, this conclusion justifies the recent Greek defence policy revision, emphasizing quality, capital equipment and flexibility of forces. This revision aims at satisfying the security requirements of the alliance and the increasing demands of an arms race against Turkey. 相似文献
479.
Carl Lundgren 《The Nonproliferation Review》2013,20(2):361-374
Nuclear optimists and pessimists disagree on whether the odds of nuclear war are low or high. This viewpoint assesses the odds of nuclear war over the past sixty-six years, exploring three pathways to nuclear war: an international crisis leading directly to nuclear war, an accident or misperception leading to nuclear escalation or nuclear retaliation against an imaginary attack, and a general conventional war leading to nuclear war. The assessment is based on the application of Bayes's theorem and other statistical reasoning and finds that the expected probability of nuclear war during this historical period was greater than 50 percent. This level of risk is unacceptably high. It is therefore urgent that effective measures be taken to substantially reduce the risk of nuclear war. 相似文献
480.
Dennis M. Gormley 《The Nonproliferation Review》2013,20(2):123-139
ABSTRACTThe dangers and risks of employing a Conventional Prompt Global Strike (CPGS) capability greatly exceed the benefits. More suitable, if less prompt, alternatives exist to deal with fleeting targets. Even a niche CPGS capability—consisting of approximately twenty systems—carries risks, to say nothing of proposals to develop hundreds or more. Most dangerously, CPGS could stir the pre-emption pot, particularly vis-à-vis states that correctly perceive to be within the gunsights of US CPGS weapons; other states, too, may feel emboldened to emulate this US precedent and undertake their own form of prompt, long-range strike capability. Compressed circumstances surrounding such a scenario could foster unwanted erratic behavior, including the misperception that the threatening missile carries a nuclear weapon. But the true Achilles's heel of the CPGS concept is the unprecedented demands it places on the intelligence community to provide decision makers with “exquisite” intelligence within an hour timeframe. Such compressed conditions leave decision makers with virtually no time to appraise the direct—and potentially unintended—consequences of their actions. 相似文献