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Many dynamic problems in economics are characterized by large state spaces which make both computing and estimating the model infeasible. We introduce a method for approximating the value function of high-dimensional dynamic models based on sieves and establish results for the (a) consistency, (b) rates of convergence, and (c) bounds on the error of approximation. We embed this method for approximating the solution to the dynamic problem within an estimation routine and prove that it provides consistent estimates of the modelik’s parameters. We provide Monte Carlo evidence that our method can successfully be used to approximate models that would otherwise be infeasible to compute, suggesting that these techniques may substantially broaden the class of models that can be solved and estimated.

Modelling and forecasting interval-valued time series (ITS) have received increasing attention in statistics and econometrics. An interval-valued observation contains more information than a point-valued observation in the same time period. The previous literature has mainly considered modelling and forecasting a univariate ITS. However, few works attempt to model a vector process of ITS. In this paper, we propose an interval-valued vector autoregressive moving average (IVARMA) model to capture the cross-dependence dynamics within an ITS vector system. A minimum-distance estimation method is developed to estimate the parameters of an IVARMA model, and consistency, asymptotic normality and asymptotic efficiency of the proposed estimator are established. A two-stage minimum-distance estimator is shown to be asymptotically most efficient among the class of minimum-distance estimators. Simulation studies show that the two-stage estimator indeed outperforms other minimum-distance estimators for various data-generating processes considered.

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

University rankings and metrics have become an increasingly prominent basis of student decisions, generalized university reputation, and the resources university’s attract. We review the history of metrics in higher education and scholarship about the influence of ranking on the position and strategic behavior of universities and students. Most quantitative analyses on this topic estimate the influence of change in university rank on performance. These studies consistently identify a small, short-lived influence of rank shift on selectivity (e.g., one rank position corresponds to ≤1% more student applicants), comparable to ranking effects documented in other domains. This understates the larger system-level impact of metrification on universities, students, and the professions that surround them. We explore one system-level transformation likely influenced by the rise of rankings. Recent years have witnessed the rise of enrollment management and independent educational consultation. We illustrate a plausible pathway from ranking to this transformation: In an effort to improve rankings, universities solicit more applications from students to reduce their acceptance rate. Lower acceptance rates lead to more uncertainty for students about acceptance, leading them to apply to more schools, which decreases the probability that accepted students will attend. This leads to greater uncertainty about enrollment for students and universities and generates demand for new services to manage it. Because these and other system-level transformations are not as cleanly measured as rank position and performance, they have not received the same treatment or modeling attention in higher education scholarship, despite their importance for understanding and influencing education policy.

Miller McPherson's approach to measuring the inherent duality of organizational forms and the environmental niches that they occupy is adapted and applied to an analysis of the institutional field of (outdoor) poverty relief organizations operating in New York City (1888–1917). In contrast to McPherson's approach that emphasizes how organizations are differentially arrayed within “Blau space,” this chapter focuses on how organizational forms are distributed across an institutional “logic space” that is itself dually ordered and defined by the kinds of organizational forms that are understood to exist. The resulting niche maps are employed to trace out the jurisdictional conflicts that erupted during the Progressive Era between two competing organizational forms – scientific charities and settlement houses – each of which embodied a particular vision and practice for delivering social relief to the poor.

This chapter describes how conversational computer agents have been used in collaborative problem-solving environments. These agent-based systems are designed to (a) assess the students’ knowledge, skills, actions, and various other psychological states on the basis of the students’ actions and the conversational interactions, (b) generate discourse moves that are sensitive to the psychological states and the problem states, and (c) advance a solution to the problem. We describe how this was accomplished in the Programme for International Student Assessment (PISA) for Collaborative Problem Solving (CPS) in 2015. In the PISA CPS 2015 assessment, a single human test taker (15-year-old student) interacts with one, two, or three agents that stage a series of assessment episodes. This chapter proposes that this PISA framework could be extended to accommodate more open-ended natural language interaction for those languages that have developed technologies for automated computational linguistics and discourse. Two examples support this suggestion, with associated relevant empirical support. First, there is AutoTutor, an agent that collaboratively helps the student answer difficult questions and solve problems. Second, there is CPS in the context of a multi-party simulation called Land Science in which the system tracks progress and knowledge states of small groups of 3–4 students. Human mentors or computer agents prompt them to perform actions and exchange open-ended chat in a collaborative learning and problem-solving environment.

In this paper, I compare Theodore Schatzki’s practice theory, the existential phenomenology of Martin Heidegger upon whom Schatzki drew in its formation, and my own theory of institutional logics which I have sought to develop as a religious sociology of institution. I examine how Schatzki and I both differently locate our thinking at the level of practice. In this essay I also explore the possibility of appropriating Heidegger’s religious ontology of worldhood, which Schatzki rejects, in that project. My institutional logical position is an atheological religious one, poly-onto-teleological. Institutional logics are grounded in ultimate goods which are praiseworthy “objects” of striving and practice, signifieds to which elements of an institutional logic have a non-arbitrary relation, sources of and references for practical norms about how one should have, make, do or be that good, and a basis of knowing the world of practice as ordered around such goods. Institutional logics are constellations co-constituted by substances, not fields animated by values, interests or powers.

Because we are speaking against “values,” people are horrified at a philosophy that ostensibly dares to despise humanity’s best qualities. For what is more “logical” than that a thinking that denies values must necessarily pronounce everything valueless? Martin Heidegger, “Letter on Humanism” (2008a, p. 249).