Portfolio Analysis of Layered Security Measures

Layered defenses are necessary for protecting the public from terrorist attacks. Designing a system of such defensive measures requires consideration of the interaction of these countermeasures. In this article, we present an analysis of a layered security system within the lower Manhattan area. It shows how portfolios of security measures can be evaluated through portfolio decision analysis. Consideration is given to the total benefits and costs of the system. Portfolio diagrams are created that help communicate alternatives among stakeholders who have differing views on the tradeoffs between security and economic activity.     

基于工作过程的高职商务英语课程体系构建研究

针对目前我国高职商务英语课程体系存在的问题,在社会和市场广泛调研的基础上,从典型工作任务归纳、学习领域课程开发、学习情境设计和配套设施建设四个方面提出高职商务英语课程体系构建方案。     

Accepting and Negotiating Service Users' Choices in Mental Health Transition Meetings

Across Western welfare regimes, policies emphasize that service users should have more choices regarding their services. This article examines how service choices are presented, responded to and decided in interactions between service users and professionals in mental health transition meetings. Choice is often associated with consumerist user involvement ideas, but in mental health choice also relates to the democratic user involvement approach and to shared decision making between professionals and service users. The results of the study show that professionals construct service users as consumers by offering service options in choice making sequences, expecting users to make appropriate choices. Service users mostly act like consumers by responding to these choice options. However, the study also demonstrates that the professionals do not always accept the user's first choice but respond to them as non‐preferred. Sometimes, they also suggest choices on behalf of the users. In these ‘non‐accepting’ sequences, choices are negotiated in interaction between the parties, rather than users acting as autonomous choice makers. The sequences are based on two kinds of professional reasoning: first, the professional‐led needs assessment and, second, the structure of the service package that the user is being offered. This negotiation has elements of shared decision making and the ‘logic of care’. But it also has elements of paternalist control which challenge both consumerist and democratic service user involvement and suggests consideration of more collectively oriented service user actions.     

Simultaneous sparse model selection and coefficient estimation for heavy-tailed autoregressive processes

We propose a sparse coefficient estimation and automated model selection procedure for autoregressive processes with heavy-tailed innovations based on penalized conditional maximum likelihood. Under mild moment conditions on the innovation processes, the penalized conditional maximum likelihood estimator satisfies a strong consistency, O_P(N^?1/2) consistency, and the oracle properties, where N is the sample size. We have the freedom in choosing penalty functions based on the weak conditions on them. Two penalty functions, least absolute shrinkage and selection operator and smoothly clipped average deviation, are compared. The proposed method provides a distribution-based penalized inference to AR models, which is especially useful when the other estimation methods fail or under perform for AR processes with heavy-tailed innovations [Feigin, Resnick. Pitfalls of fitting autoregressive models for heavy-tailed time series. Extremes. 1999;1:391–422]. A simulation study confirms our theoretical results. At the end, we apply our method to a historical price data of the US Industrial Production Index for consumer goods, and obtain very promising results.     

How to conduct a Narrative Policy Framework study

The Narrative Policy Framework has a growing number of researchers seeking to apply the framework in policy process scholarship. This article is intended to assist those interested in conducting an NPF study that is ‘clear enough to be wrong’ (Sabatier, 2000). While graduate programs offer critical methodological training, this article focuses on the specific application of the NPF to research inquiries about the role of policy narratives in the policy process. We approach our discussion by examining various decisions in the research process and include a detailed discussion of specifying the model and obtaining narrative data. We also point out areas for further investigation.     

Strategy as engagement: What organization strategy can learn from military strategy

Strategy process and practice research has illuminated the internal dynamics of strategy work – at the cost of backgrounding processes and practices that relate to engagement with external actors. In this conceptual paper, we argue for an extension of this body of work by shifting the focus of research from internal practices and processes towards externally oriented practices of engagement. We do so by critically building on the military strategy literature and develop the concept of strategy as engagement. This concept suggests understanding the role of strategy as bridge between policy and tactics; the importance of grand strategy as the making of policy; and the need to focus attention on tactics as distributed collective action. Thus, we contribute to strategy process and practice research through 1) extending its repertoire to practices of engagement and 2) broadening its epistemic foundation through a critical reading of military strategy.     

Time varying long memory parameter estimation for locally stationary long memory processes

The semiparametric estimators of time varying long memory parameter are investigated for locally stationary long memory processes. The GPH estimator and the local Whittle estimator are considered. Under some mild regularity assumptions, the weak consistency and the asymptotic normality of the estimators are obtained. The finite sample performance of the estimators is discussed through a small simulation study.     

Expansion and estimation of Lévy process functionals in nonlinear and nonstationary time series regression

In this article, we develop a series estimation method for unknown time-inhomogeneous functionals of Lévy processes involved in econometric time series models. To obtain an asymptotic distribution for the proposed estimators, we establish a general asymptotic theory for partial sums of bivariate functionals of time and nonstationary variables. These results show that the proposed estimators in different situations converge to quite different random variables. In addition, the rates of convergence depend on various factors rather than just the sample size. Finite sample simulations are provided to evaluate the finite sample performance of the proposed model and estimation method.     

Against the De Minimis Principle

According to the class of de minimis decision principles, risks can be ignored (or at least treated very differently from other risks) if the risk is sufficiently small. In this article, we argue that a de minimis threshold has no place in a normative theory of decision making, because the application of the principle will either recommend ignoring risks that should not be ignored (e.g., the sure death of a person) or it cannot be used by ordinary bounded and information-constrained agents.