Polynomial-time Computation of Exact Correlated Equilibrium in Compact Games

In a landmark paper, Papadimitriou and Roughgarden described a polynomial-time algorithm ("Ellipsoid Against Hope") for computing sample correlated equilibria of concisely-represented games. Recently, Stein, Parrilo and Ozdaglar showed that this algorithm can fail to find an exact correlated equilibrium, but can be easily modified to efficiently compute approximate correlated equilibria. Currently, it remains unresolved whether the algorithm can be modified to compute an exact correlated equilibrium. We show that it can, presenting a variant of the Ellipsoid Against Hope algorithm that guarantees the polynomial-time identification of exact correlated equilibrium. Our new algorithm differs from the original primarily in its use of a separation oracle that produces cuts corresponding to pure-strategy profiles. As a result, we no longer face the numerical precision issues encountered by the original approach, and both the resulting algorithm and its analysis are considerably simplified. Our new separation oracle can be understood as a derandomization of Papadimitriou and Roughgarden's original separation oracle via the method of conditional probabilities. Also, the equilibria returned by our algorithm are distributions with polynomial-sized supports, which are simpler (in the sense of being representable in fewer bits) than the mixtures of product distributions produced previously; no tractable algorithm has previously been proposed for identifying such equilibria.Comment: 15 page

Review of Australian land use mapping and land management practice

Land use information plays a vital role in effective management of natural resources in any country. The land use and land cover mapping is always a dynamic issue in every country because of the changing nature of the land use. Australia is experiencing similar traits. Knowledge of land use change patterns has important implications for sustainable development and sustainable environmental management. It helps in the management of water, soil, nutrients, plants and animals and provides relationship between land use dynamics and economics and social condition in urban and regional area. Although Australia has a long history of land use mapping and land management practice, no systematic study of the land use mapping status and land management practice can be confirmed. With the establishment of the Commonwealth Advisory Committee on the Environment in June 1972, later known as the Australian Advisory Committee on the Environment, the Australian government gave prime importance to land use and the environment. The committee recommended to the government that “Land use is fundamental to any consideration of the environment.” The committee also found an urgent need for an efficient, co-ordinated, and comprehensive system of national and state land use planning. Subsequently, many organizations and institutions like BRS, ACLUMP, CSIRO, QDERM, and DPI started on land cover/land use mapping from national to catchment level and many Land Care groups began working on land management the local level. This study reviews the status of the land use mapping and land management practices as implemented in Australi

Deep Learning-based Prescription of Cardiac MRI Planes.

PurposeTo develop and evaluate a system to prescribe imaging planes for cardiac MRI based on deep learning (DL)-based localization of key anatomic landmarks.Materials and methodsAnnotated landmarks on 892 long-axis (LAX) and 493 short-axis (SAX) cine steady-state free precession series from cardiac MR images were retrospectively collected between February 2012 and June 2017. U-Net-based heatmap regression was used for localization of cardiac landmarks, which were used to compute cardiac MRI planes. Performance was evaluated by comparing localization distances and plane angle differences between DL predictions and ground truth. The plane angulations from DL were compared with those prescribed by the technologist at the original time of acquisition. Data were split into 80% for training and 20% for testing, and results confirmed with fivefold cross-validation.ResultsOn LAX images, DL localized the apex within mean 12.56 mm ± 19.11 (standard deviation) and the mitral valve (MV) within 7.68 mm ± 6.91. On SAX images, DL localized the aortic valve within 5.78 mm ± 5.68, MV within 5.90 mm ± 5.24, pulmonary valve within 6.55 mm ± 6.39, and tricuspid valve within 6.39 mm ± 5.89. On the basis of these localizations, average angle bias and mean error of DL-predicted imaging planes relative to ground truth annotations were as follows: SAX, -1.27° ± 6.81 and 4.93° ± 4.86; four chambers, 0.38° ± 6.45 and 5.16° ± 3.80; three chambers, 0.13° ± 12.70 and 9.02° ± 8.83; and two chamber, 0.25° ± 9.08 and 6.53° ± 6.28, respectively.ConclusionDL-based anatomic localization is a feasible strategy for planning cardiac MRI planes. This approach can produce imaging planes comparable to those defined by ground truth landmarks.© RSNA, 2019 Supplemental material is available for this article

A quantum magnetic RC circuit

We propose a setup that is the spin analog of the charge-based quantum RC circuit. We define and compute the spin capacitance and the spin resistance of the circuit for both ferromagnetic (FM) and antiferromagnetic (AF) systems. We find that the antiferromagnetic setup has universal properties, but the ferromagnetic setup does not. We discuss how to use the proposed setup as a quantum source of spin excitations, and put forward a possible experimental realization using ultracold atoms in optical lattices

Integrating acquisitions : keys to unlocking the value of synergy

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management, 1999.Includes bibliographical references (leaves 122-126).The ability of mergers and acquisition transactions to generate enhanced shareholder value often hinges on successful integration. Our thesis examines this critical phase of merger activity. Through six discrete case studies and interviews with the individuals who led those transactions, we identify the important discriminators that differentiate success from failure. In addition, we highlight the firms and processes that are emerging as benchmarks in this area.by Albert K. Killen and Kevin P. Lawlor.M.B.A

From New Public Management to Lean thinking: understanding and managing 'potentially avoidable failure induced demand'

The central objective of this thesis is to investigate, understand and explain the conditions under which the administrative problem known as potentially avoidable failure induced demand (PAFID) arises in UK public services and might be prevented. PAFID is defined as “customer contacts that appear to be precipitated by earlier failures, such as failures to do things right first time, which cause additional and potentially avoidable demands to impinge upon public services”. A secondary objective of the thesis is to establish how, and under what better conditions, the public sector could successfully exploit the management paradigm called Lean thinking, as an alternative to the current New Public Management method, in order to address the PAFID problem. An analysis of the results from three case-studies conducted in UK local authority settings confirms that nearly half of all customer contacts in high-volume services such as housing benefits are potentially avoidable. The extrapolation of this finding to the contact volumes and handling costs in one UK council alone suggests possible savings of more than £1 million a year. The potential benefits that are available to the case-study councils and nearly 500 other local councils, together with numerous other providers of UK public services, are also very substantial. A variety of conceptual lenses are applied to the PAFID problem in order to generate alternative explanations and policy options. This thesis makes a number of contributions to public sector management theory and practice, including the finding that councils might reduce principal-agent problems that add to PAFID by espousing more supportive and enabling environments, and by adopting systems-oriented approaches that acknowledge the complex and subjective nature of real-world problems. The findings also suggest that, while the deployment of Lean ‘tools’ can result in short-term savings and performance improvements, the adoption of Lean thinking as a comprehensive management approach is more likely to bring about fundamental changes

Adolescents Growing Up in Stressful Environments, Dual Diagnosis, and Sources of Success

This article considers the social and psychological challenges to youth in contemporary society. The authors examine the variety of social impediments that face youths in most of our social institutions, from schools and the juvenile justice system to the family. They underscore the need for prevention, health promotion, and comprehensive assessment. Further, they assert that ‘‘dual diagnosis’’ needs to be considered not as a ‘‘special population’’ but as the typical or common experience of at-risk youths once they are diagnosed at mental health centers or juvenile justice reception and diagnostic centers. They conclude that evidence-based assessment, intervention, prevention, and health promotion will start to unravel the matter of misdirected diagnosis and treatment. The articles in this special issue amply illustrate what can be done