cssi/SciSciGPT-SciSciNet huggingface dataset:
Planar lower envelope of monotone polygonal chains

An algorithm to find the lower envelope of monotone polygonal chains is proposed.Simpler than known methods and requires no complex data structures.Applies to output-sensitive construction of line segment lower envelope. A simple linear search algorithm running in O ( n + m k ) time is proposed for constructing the lower envelope of k vertices from m monotone polygonal chains in 2D with n vertices in total. This can be applied to output-sensitive construction of lower envelopes for n arbitrary line segments in optimal O ( n log ? k ) time, where k is the output size. Compared to existing output-sensitive algorithms for lower envelopes, this is simpler to implement, does not require complex data structures, and is a constant factor faster.
Density-Independent, Scalable Search in Ad Hoc Networks

We analyze the asymptotic cost of discovering a route within a flat ad hoc network and we show that one can discover a route with cost that is proportional only to the area of the network, which is independent of the number of network nodes. Furthermore, we show that this is optimal and that bordercasting (a query propagation protocol where a node retransmits a query to a set of nodes at some hop-distance away) possesses this density-independence property. We present the design of bordercast and the associated maintenance protocols, and we evaluate their performance. In particular, we highlight that the aggregation of local information by bordercasting at each network node is a fundamental building block for the construction of scalable protocols in flat ad hoc networks.
Online Appendix to Should the Social Security Trust Fund hold Equities? An Intergenerational Welfare Analysis

In a stochastic economy with overlapping generations, fiscal policy affects the allocation of aggregate risks. The paper shows how to compute the welfare effects of marginal policy changes that shift risk across cohorts, in general and for an application to social security equity investments. I estimate the relevant correlations between macroeconomic shocks and equity returns from 1874-1996 U.S. data, calibrate the model, and find positive welfare effects for equity investments. Since stock returns are positively correlated with social security's wage-indexed benefit obligations, equity investments would also help to stabilize the payroll tax rate. (Copyright: Academic Press)
Large-Scale Coronal Heating, Clustering of Coronal Bright Points, and Concentration of Magnetic Flux

By combining quiet-region Fe XII coronal images from SOHO/EIT with magnetograms from NSO/Kitt Peak and from SOHO/MDI, we show that the population of network coronal bright points and the magnetic flux content of the network are both markedly greater under the bright half of the large-scale quiet corona than under the dim half. These results (1) support the view that the heating of the entire corona in quiet regions and coronal holes is driven by fine-scale magnetic activity (microflares, explosive events, spicules) seated low in the magnetic network, and (2) suggest that this large-scale modulation of the magnetic flux and coronal heating is a signature of giant convection cells.
Chinese Trade Expansion and Development and Growth in Today's World

The current Chinese trade expansion brings benefit to many parties, both outside and inside the Chinese Mainland. It also poses huge challenges to others, in foreign countries, also in China. The event is important for its own sake, but also what it implies when rapid growth happens to countries large in population and size (including India, Russia, Brazil). It has to be understood in context. Conventional wisdom in economics and popular explanations cannot explain Chinese growth, let alone its implications. Only with suitable adaptations of what the economic discipline has to offer, can one assess the nature of what we observe and the policy measures needed for today. Like other episodes after Industrial Revolution, the late industrialization in China also relies on outside technology, often gained through trade and foreign investment. Because of the de-colonization after 1945, such growth can succeed even with scanty domestic resource. Like other East Asian economies, participation in cross border supply chains along its neighbors offers China an effective entree. What makes China different from the other East Asian economies is size. The presence of a huge labor reserve keeps wage down, profit up, attracts foreign investment coming with technology, but may also lead to deteriorated terms of trade and income inequality at home, de-industrialization and the loss of development opportunities abroad, also resource shortage and environment damage, some of these are irreversible in nature. Over all, the development is the result of efficiency gain, which is basically desirable. It takes international cooperation to steer such development toward mutually beneficial paths. It is also desirable for China to accelerate job creation at home and avoid irreversible environment harm. These are well recognized by Chinese decision makers. More can be done.
The Chicago Plan and New Deal Banking Reform

The history of the legislative changes in the financial system, which occurred during the 28 months from Franklin D. Roosevelt’s inauguration, in March 1933, until the passage of the Banking Act of 1935 has been well documented (Burns, 1974; Kennedy, 1973). This period saw the enactment of the Emergency Banking Act, the Banking Acts of 1933 and 1935, as well as reforms of the stock market and agricultural credit. The existing histories have given us detailed examinations of the political maneuvering involved in the passage of the legislation, but they have neglected the role of the ‘Chicago plan’ — the 1933 proposal put forward, in a series of memoranda by economists at the University of Chicago, to abolish the fractional reserve system and impose 100 per cent reserves on demand deposits. The proposal was known to the Roosevelt administration prior to the passage of the Banking Act of 1933, and later led directly to legislation introduced by Senator Bronson Cutting of New Mexico, and other Progressives, as part of the debate over the Banking Act of 1935. The influence of the Chicago plan was felt even before Irving Fisher’s more widely known, and largely unsuccessful, efforts to enlist Roosevelt’s support for the 100 per cent reserve plan (Allen, 1977, 1991).
The Impact of Why/AutoTutor on Learning and Retention of Conceptual Physics

Why/AutoTutor is an intelligent tutoring system for conceptual physics that guides learning through tutorial dialog in natural language. It adapts to student contributions within dialog turns in both a conversationally appropriate and pedagogically effective manner. It uses an animated agent with synthesized speech to engage the student and provide a human-like conversational partner. Why/AutoTutor serves as a learning scaffold throughout the tutoring session and facilitates active knowledge construction on the part of the student. Why/AutoTutor has recently been compared with an ideal information delivery system in order to assess differences in learning gains, the factors that contribute to those gains, and the retention of that knowledge.
Promoting Fruit and Vegetable Consumption: Are Coupons More Effective than Pure Price Discounts?

The U.S. Department of Agriculture administers food and nutrition assistance programs that promote fruit and vegetable consumption. But consumption remains relatively low among program recipients as well as among the general U.S. population. The perceived high cost of produce is often cited as a deterrent to more consumption. This study looks at coupons and price discounts, two methods of lowering the cost of fruits and vegetables, and uses household purchase data and a consumer demand model to examine each method. Coupons influence consumer behavior through a price-discount effect and an informational/advertising effect. Because of this dual effect, the use of a coupon to increase fruit and vegetable purchases may be more effective than a pure price-discount policy or other noncoupon promotion. Assuming a coupon usage rate of 10 to 50 percent, lowering prices through a “10 percent off” coupon would increase average weekly fruit and vegetable quantities purchased by 2 to 11 percent, as compared with a 5- to 6-percent effect for a pure price discount.
Economywide Effects of a Multilateral Trade Liberalization in Agriculture by Industrialized Market Economies on Canada, Japan, and the European Communities

This paper analyzes the economywide impacts of a multilateral trade liberalization in agriculture by industrialized market economies on Canada, Japan, and the European Market. The analysis takes changes in world market prices and in the price structures of the three countries from results obtained by SWOPSIM. It compares simulations of the free-trade scenarios with baseline results obtained over the period 1986-2000 for each of the countries. Two types of responses are reported: the immediate response and those over the long run. Results from the analyses indicate that agriculture contracts in Japan and the EC and expands in Canada when agricultural trade is no longer protected. Gains from such policies are sufficiently large to compensate farmers in both the EC and Japan. Adjustments in factor markets are strong in all three countries analyzed.
Online Justification for Tabled Logic Programs

Justification is the process of constructing evidence, in terms of proof, for the truth or falsity of an answer derived by tabled evaluation. The evidence is most easily constructed by post-processing the memo tables created during query evaluation. In this paper we introduce online justification, based on program transformation, to efficiently construct the evidence during query evaluation, while adding little overhead to the evaluation itself. Apart from its efficiency, online justification separates evidence generation from exploration thereby providing flexibility in exploring the evidence either declaratively or procedurally. We present experimental results obtained on examples that construct large evidences which demonstrate the scalability of online justification.
Consumer Preferences for Organic and Fair Trade Chocolate: Implications for Sustainable Agriculture in the Developing World

This paper examines results of a consumer survey measuring consumer awareness and attitudes concerning two labels, certified organic and certified Fair Trade. These labels provide information about the social, economic and environmental sustainability of the production and marketing practices of goods imported from the developing world. Conjoint analysis is used to measure how consumers value organic and fair trade compared to other attributes like price. Results indicate favorable attitudes and value placed on these the sustainable attributes, and imply a role for these labels to provide incentives for the adoption of more sustainable practices.
The Legal Clinic Is More Than a Sign on the Door: Transforming Law School Education in Revolutionary Egypt

There is little consensus on what the January 25, 2011 Revolution in Egypt stands for, or whether Egyptians are living through the Revolution or in a post-Revolutionary State. Skeptics say that what occurred is the overthrow of an autocratic President, the retention of an Old Guard military and civil service establishment, and the potential for free and fair national elections. They contend, however, that this seminal event in the "Arab Spring" produced no revolutionary leadership and no clear platform or message. Is there a role for law schools in the revolutionary transformation? In this article, the author describes the changes taking place in Egyptian law schools, and how these changes can enhance the objectives of the Revolution. He next defines the critical elements of clinical legal education and the importance of social justice in the clinical model. He then identifies obstacles to making changes in the educational system. Finally, he makes recommendations for building a foundation of innovation, expertise, and institutional support before embarking on the ambitious establishment of a clinical component within the law faculty. After all, the Legal Clinic is more than a room with a sign on the door.
Macular lesions secondary to choroidal vascular disorders.

The various macular lesions secondary to choroidal vascular disorders are classified, for descriptive purposes, into five categories. The role of the choroidal vascular disorders in each of these groups is reviewed and discussed; in some conditions it is well-established, in others it is probable, while in still others it remains a possibility.
Dynamic component substitutability analysis

This paper presents an automated and compositional procedure to solve the substitutability problem in the context of evolving software systems. Our solution contributes two techniques for checking correctness of software upgrades: 1) a technique based on simultaneous use of over and under approximations obtained via existential and universal abstractions; 2) a dynamic assume-guarantee reasoning algorithm – previously generated component assumptions are reused and altered on-the-fly to prove or disprove the global safety properties on the updated system. When upgrades are found to be non-substitutable our solution generates constructive feedback to developers showing how to improve the components. The substitutability approach has been implemented and validated in the ComFoRT model checking tool set and we report encouraging results on an industrial benchmark.
Explaining Sudden Stops, Growth Collapse and BOP Crises: The Case of Distortionary Output Taxes

The paper discusses a model in which growth is a negative function of fiscal burden. Moreover, growth discontinuously switches from high to low as fiscal burden reaches a critical level Growth collapse is associated with a sudden stop of capital inflows, real depreciation and a drop in output (driven by a fall in the output of nontradables)–all of which have occurred during recent financial crises in emerging markets. The monetary version of the model is employed to show that balance of payments (BOP) crises could be a result of fiscal distortions. In particular, it is further argued that BOP crisis could be a justifiable central bank response to growth collapse, although realistic circumstances may make this response highly ineffective. An important policy implication of the model is that in order to avoid sudden stop crises, policymakers should aim at improving fiscal institutions. Lowering the fiscal deficit is highly effective in the medium term, but could be counterproductive in the short run if it relies on higher taxes.
On higher real and stable ranks for CCR C*-algebras

We calculate the real rank and stable rank of CCR algebras which either have only finite dimensional irreducible representations or have finite topological dimension. We show that either rank of A is determined in a good way by the ranks of an ideal I and the quotient A/I in four cases: When A is CCR; when I has only finite dimensional irreducible representations; when I is separable, of generalized continuous trace and finite topological dimension, and all irreducible representations of I are infinite dimensional; or when I is separable, stable, has an approximate identity consisting of projections, and has the corona factorization property. We also present a counterexample on higher ranks of M(A), A subhomogeneous, and a theorem of P. Green on generalized continuous trace algebras.
Integrated architectural modeling and analysis for high-assurance command and control system design

A RealdTime Architectural Specification (RAS) approach and its application to command and control (C2) systems are presented. Our objective is to establish a formal foundation that will enable us to integrate existing rich but fragmented formal techniques for system specification and verification into a practical and scaleable formal engineering method to support the design and development of highly reliable realdtime distributed systems. The contribution of RAS is twofold: First, it provides a formal system that integrates system’s timing requirements and requirements propagation into the process of architectural modeling and design in such a way that allows us to systematically enforce that the requirements are met in every step of the design process. Second, it offers an incremental and more scaleable approach for design modeling. These two features together make RAS a suitable model for the design of C2 systems. We further present an incremental method for verifying timing properties of an RAS model that helps to reduce the complexity of analysis both at a given design level and across different design levels.
IGNACIO ARELLANO, Poesía satírico burlesca de Quevedo: estudio y anotación filológica de los sonetos

Es este uno de los libros de conjunto mas completos que se hayan escrito sobre la poesia satirica de Quevedo. La seriedad de la empresa y la riqueza de datos que ofrece al estudioso de la obra de Quevedo y de la poesia barroca en general aseguran su valor y su exito.
A Hypergraph Dictatorship Test with Perfect Completeness

A hypergraph dictatorship test is first introduced by Samorodnitsky and Trevisan and serves as a key component in their unique games based ${\operatorname{PCP}}$ construction. Such a test has oracle access to a collection of functions and determines whether all the functions are the same dictatorship, or all their low degree influences are o (1). Their test makes q *** 3 queries, has amortized query complexity $1+O\left(\frac{\log q}{q}\right)$, but has an inherent loss of perfect completeness. In this paper we give an (adaptive) hypergraph dictatorship test that achieves both perfect completeness and amortized query complexity $1+O\left(\frac{\log q}{q}\right)$.
The Fiscal Impact of Foreign Aid in Rwanda : A Theoretical and Empirical Analysis

The inflow of large quantities of foreign aid into Rwanda since 1994 can have potential adverse effects such as aid dependency via a significant negative effect on tax efforts and on public investments. This paper carries out a theoretical and empirical study to examine these issues. The theoretical part develops a model in which the recipient government decides on the optimal level of tax and optimally allocates total government revenue between current expenditure and public investment. The theoretical model makes it possible to empirically test whether an increase in aid is likely to reduce the optimal tax rate and the proportion of public expenditure allocated to public investment. The econometric analysis uses time series data on Rwanda to show, in line with other studies in the literature, a negative relationship between increased aid and the tax rate; but the magnitude of the effects are extremely small. In the case of Rwanda, reforms to the tax administration and expansion of the tax base have had mitigating effects. As far as the effect on public investment, the overall effect was negative in the past; however, since 1995 the direction of this effect has changed.
Network of Tinkerers: A Model of Open-Source Technology Innovation

Technologies such as airplanes, personal computers, and open-source software programs have been developed by networks of hobbyists, not firms or other formal organizations. This paper models individuals who develop a technology. In the model, agents called “tinkerers” have an exogenous interest in improving a technology according to their own criteria, and do not see a way to profit from it. Under these conditions, tinkerers prefer to make an open-source technology agreement than to work alone. The members of the agreement form an information network with economies of scale. pecialists in the group may devote their energies to expanding or managing it rather than working on the technology itself. Endogenously there are incentives to standardize on designs and descriptions of the technology, and to specialize in a particular aspect. A tinkerer in the network who sees how to produce a suciently profitable product may create a startup firm and choose to exit
A Novel Test Method for Measuring Mechanical Properties at the Small-Scale: The Theta Specimen

A test method has been developed for measuring mechanical properties of material structures at the small-scale. Round or hexagonal rings are compressed vertically on their ends thereby creating a uniform tension stress in a horizontal crossbar that serves as the gauge section. The compression loading scheme is simple and eliminates the need for special grips. A conventional nanoindentation hardness machine serves as a small-scale universal testing machine that applies load and monitors displacement. Prototype miniature silicon specimens were fabricated by deep reactive ion etching (DRIE) of a single crystal wafer and were tested to fracture. Finite element analysis confirmed that the stress distribution was very uniform in the web portion of the specimen. The theta specimen is a versatile configuration and has great potential for use with a variety of materials and for testing extremely small structures.
Three Mile Island

This article is reproduced from the previous edition with updated references, volume 4, pp 184–186, © 2005, Elsevier Inc.
Efficient enumeration of instantiations in Bayesian networks

Over the past several years Bayesian networks have been applied to a wide variety of problems. A central problem in applying Bayesian networks is that of finding one or more of the most probable instantiations of a network. In this paper we develop an efficient algorithm that incrementally enumerates the instantiations of a Bayesian network in decreasing order of probability. Such enumeration algorithms are applicable in a variety of applications ranging from medical expert systems to model-based diagnosis. Fundamentally, our algorithm is simply performing a lazy enumeration of the sorted list of all instantiations of the network. This insight leads to a very concise algorithm statement which is both easily understood and implemented. We show that for singly connected networks, our algorithm generates the next instantiation in time polynomial in the size of the network. The algorithm extends to arbitrary Bayesian networks using standard conditioning techniques. We empirically evaluate the enumeration algorithm and demonstrate its practicality.
Ferroxitosis: A cell death from modulation of oxidative phosphorylation and PKM2-dependent glycolysis in melanoma

Reliance on glycolysis is a characteristic of malignancy, yet the development of resistance to BRAF inhibitors in melanoma is associated with gain of mitochondrial function. Concurrent attenuation of oxidative phosphorylation and HIF-1α/PKM2-dependent glycolysis promotes a non-apoptotic, iron- and oxygen-dependent cell death that we term ferroxitosis. The redox cycling agent menadione causes a robust increase in oxygen consumption, accompanied by significant loss of intracellular ATP and rapid cell death. Conversely, either hypoxic adaptation or iron chelation prevents menadione-induced ferroxitosis. Ectopic expression of K213Q HIF-1α mutant blunts the effects of menadione. However, knockdown of HIF-1α or PKM2 restores menadione-induced cytotoxicity in hypoxia. Similarly, exposure of melanoma cells to shikonin, a menadione analog and a potential PKM2 inhibitor, is sufficient to induce ferroxitosis under hypoxic conditions. Collectively, our findings reveal that ferroxitosis curtails metabolic plasticity in melanoma.
Belief Functions and Parametric Models

The theory of belief functions assesses evidence by fitting it to a scale of canonical examples in which the meaning of a message depends on chance. In order to analyse parametric statistical problems within the framework of this theory, we must specify the evidence on which the parametric model is based. This article gives several examples to show how the nature of this evidence affects the analysis. These examples also illustrate how the theory of belief functions can deal with problems where the evidence is too weak to support a parametric model.
Camera pose estimation by an artificial neural network

Reconstruction of a three-dimensional scene using images taken from two views is possible if the relative pose of the cameras is known. A traditional approach to estimating the pose of the cameras uses eight pairs of corresponding points and involves the solution of a set of homogeneous equations. We propose a multi-layered feedforward network solution. Empirical results demonstrate the feasibility of using the network to recover the relative pose of the cameras in the three-dimensional world.
Cheeger-Gromov Theory and Applications to General Relativity

This paper surveys aspects of the convergence and degeneration of Riemannian metrics on a given manifold M, and some recent applications of this theory to general relativity. The basic point of view of convergence/degeneration described here originates in the work of Gromov, cf. [31]—[33], with important prior work of Cheeger [16], leading to the joint work of [18].
ELECTRICAL CONDUCTIVITY MEASUREMENTS IN THE STRATOSPHERE USING BALLOON AND PARACHUTE-BORNE BLUNT PROBES

Blunt probe electrical conductivity measurements from three balloon flights are reported in this paper. Rocket-launched, parachute-borne blunt probe experiments were conducted in conjunction with two of the flights. The float altitude balloon data were useful for studying electrical conductivity and its associated temperature and sunrise variations. The altitude dependence for the balloon conductivity data was observed to be in good agreement with the corresponding rocket measurements.
Scattering from non-spherical hydrometeors

A new theoretical formulation for scattering from a wide class of non-spherical hydrometeors has been developed recently using Waterman’s extended integral equation technique. The transition or T-matrix formulation is an exact solution to the scattering problem and computer programs have been developed to handle both homogeneous and imbedded bodies (e.g., a dielectric imbedded within another dielectric body). This theory will be briefly reviewed followed by sample computations of backscattering calculations of (a)oblate spheroidal icestones of varying sizes and eccentricities, (b)ice-stones with surface perturbations to model roughness, and (c)rough ice-stones covered with a thin coating of water. The method is realistically applicable for sizes up to D ≈3 λand for a wide range of dielectric constants. Comparisons with measurements of backscattering from a non-concentric dielectric-clad spherical perfect conductor is included.
Patterns of failure in patients with head and neck carcinoma of unknown primary treated with radiation therapy.

Background The purpose of this study was to examine patterns of failure and the relationship to radiation doses in patients with head and neck carcinoma of unknown primary (HNCUP). Methods We reviewed 85 patients with HNCUP treated with curative-intent radiation therapy (RT) during 1995 to 2012. Results There have been no failures in the pharyngeal axis. Relapse at initial neck sites of disease developed in 7 patients (8.2%). The median dose to these sites was 70 Gy (range, 63–70 Gy). Failure at neck sites without initial disease occurred in 4 patients (4.7%). The median dose was 54 Gy (range, 50–58.8 Gy). There were no contralateral failures in a small cohort of patients receiving unilateral treatment (n = 6). Percutaneous endoscopic gastrostomy (PEG) tube dependence at 12 months was 7.4%, and 2.5% at 3 years. Esophageal stricture developed in 5 patients (5.9%). Conclusion RT for HNCUP produces excellent locoregional control rates with acceptably low levels of late toxicity. Doses prescribed to sites of eventual failure did not vary significantly from those sites that were treated and remain in control. © 2015 Wiley Periodicals, Inc. Head Neck 38: E426–E431, 2016
Does the Masters Hypothesis Explain Recent Food Price Spikes

Summary and Conclusions Food prices at the bulk commodity level have trended upward since 2006 and have experienced two rather dramatic spikes, the first in 2008 and the second in 2010. Because consumers in less-developed countries devote a relatively high proportion of disposable income to food purchases, sharp increases in the price of food can be quite harmful to the health and well-being of large numbers of people. The nature and cause of the recent spikes in food prices is the subject of an acrimonious and world-wide debate. Hedge fund manager Michael W. Masters has led the charge (Masters, 2008 2009; Masters and White, 2009) that unprecedented buying pressure from new commodity index investors created a massive bubble in commodity futures prices at various times in recent years. Irwin and Sanders (2012a) use the term “Masters Hypothesis” as a short-hand label for this argument. Several well-known international organizations have been among the most ardent supporters of the Masters Hypothesis (see Robles, Torero, and von Braun, 2009; De Schutter, 2010; Herman, Kelly, and Nash, 2011; UNCTAD, 2011), arguing that index investors were a principal driver of spikes in food commodity prices since 2007.
WHY AGNOSTIC SIGN RESTRICTIONS ARE NOT ENOUGH: UNDERSTANDING THE DYNAMICS OF OIL MARKET VAR MODELS

Sign restrictions on the responses generated by structural vector autoregressive models have been proposed as an alternative approach to the use of exclusion restrictions on the impact multiplier matrix. In recent years such models have been increasingly used to identify demand and supply shocks in the market for crude oil. We demonstrate that sign restrictions alone are insufficient to infer the responses of the real price of oil to such shocks. Moreover, the conventional assumption that all admissible models are equally likely is routinely violated in oil market models, calling into question the use of posterior median responses to characterize the responses to structural shocks. When combining sign restrictions with additional empirically plausible bounds on the magnitude of the short-run oil supply elasticity and on the impact response of real activity, however, it is possible to reduce the set of admissible model solutions to a small number of qualitatively similar estimates. The resulting model estimates are broadly consistent with earlier results regarding the relative importance of demand and supply shocks for the real price of oil based on structural vector autoregressive (VAR) models identified by exclusion restrictions, but imply very different dynamics from the posterior median responses in VAR models based on sign restrictions only.
Coxeter groups and asynchronous cellular automata

The dynamics group of an asynchronous cellular automaton (ACA) relates properties of its long term dynamics to the structure of Coxeter groups. The key mathematical feature connecting these diverse fields is involutions. Group-theoretic results in the latter domain may lead to insight about the dynamics in the former, and vice-versa. In this article, we highlight some central themes and common structures, and discuss novel approaches to some open and open-ended problems. We introduce the state automaton of an ACA, and show how the root automaton of a Coxeter group is essentially part of the state automaton of a related ACA.
Latin Hypercube Sampling

This entry discusses the use of computer models for such diverse applications as safety assessments for geologic isolation of radioactive waste and for nuclear power plants; loss cost projections for hurricanes; reliability analyses for manufacturing equipment; transmission of HIV; and subsurface storm flow modelling. Such models are usually characterized by a large number of input variables (perhaps as many as a few hundred), and usually, only a handful of these inputs are important for a given response. In addition, the model response is frequently multivariate and time dependent. Latin hypercube sampling (LHS) uses a stratified sampling scheme to improve on the coverage of the k-dimensional input space for such computer models. This means that a single sample will provide useful information when some input variable(s) dominate certain responses (or certain time intervals), while other input variables dominate other responses (or time intervals). By sampling over the entire range, each variable has the opportunity to show up as important, if it indeed is important. If an input variable is not important, then the method of sampling is of little or no concern. The values of the stratified sampling scheme can be paired to ensure a desired correlation structure among the k input variables. LHS is more efficient than simple random sampling in a large range of conditions. Keywords: Latin hypercube sampling; uncertainty analysis; sensitivity analysis; rank correlation; hurricane loss projection; uncertainty importance
A Robust Probabilistic Estimation Framework for Parametric Image Models

Models of spatial variation in images are central to a large number of low-level computer vision problems including segmentation, registration, and 3D structure detection. Often, images are represented using parametric models to characterize (noise-free) image variation, and, additive noise. However, the noise model may be unknown and parametric models may only be valid on individual segments of the image. Consequently, we model noise using a nonparametric kernel density estimation framework and use a locally or globally linear parametric model to represent the noise-free image pattern. This results in a novel, robust, redescending, M- parameter estimator for the above image model which we call the Kernel Maximum Likelihood estimator (KML). We also provide a provably convergent, iterative algorithm for the resultant optimization problem. The estimation framework is empirically validated on synthetic data and applied to the task of range image segmentation.
Short-term Variations in the Galactic Environment of the Sun

We review the long-term variations in the galactic environment in the vicinity of the solar system. These include changes in the cosmic ray flux, in the pressure of the different interstellar components and possibly even gravitational tides. On very long time scales, the variations arise from the variable star formation rate of the Milky Way, while on shorter scales, from passages through the galactic spiral arms and vertical oscillations relative to the galactic plane. We also summarize the various records of past variations, in meteorites, in the ocean sea floor and even in various paleoclimatic records.
Problems of Rational Agricultural Land Use in the Ukraine

Ukraine is one of the world's most extensively farmed areas; 70 percent of its total area is devoted to agricultural production. With this intensive agricultural use, Ukraine is experiencing increasingly severe environmental and natural resource problems, especially soil erosion. Saiko outlines some options for a return to more natural landscape and vegetative patterns that would help restore ecological stability.
Nanophotonics in material-systems of Large Sizes

Recent nano-fabrication developments enabled implementation of many nanophotonic techniques to macroscopic scales, which is crucial for many applications of interest (e.g. energy conversion, displays, lighting). Some exciting new opportunities in this area will be presented.
Knowledge-based decision model construction for hierarchical diagnosis: a preliminary report

Numerous methods for probabilistic reasoning in large, complex belief or decision networks are currently being developed. There has been little research on automating the dynamic, incremental construction of decision models. A uniform value-driven method of decision model construction is proposed for the hierarchical complete diagnosis. Hierarchical complete diagnostic reasoning is formulated as a stochastic process and modeled using influence diagrams. Given observations, this method creates decision models in order to obtain the best actions sequentially for locating and repairing a fault at minimum cost. This method construct decision models incrementally, interleaving probe actions with model construction and evaluation. The method treats meta-level and base-level tasks uniformly. That is, the method takes a decision-theoretic look at the control of search in causal pathways and structural hierarchies.
Intercausal reasoning with uninstantiated ancestor nodes

Intercausal reasoning is a common inference pattern involving probabilistic dependence of causes of an observed common effect. The sign of this dependence is captured by a qualitative property called product synergy. The current definition of product synergy is insufficient for intercausal reasoning where there are additional uninstantiated causes of the common effect. We propose a new definition of product synergy and prove its adequacy for intercausal reasoning with direct and indirect evidence for the common effect. The new definition is based on a new property matrix half positive semi-definiteness, a weakened form of matrix positive semi-definiteness.
Kinetic solution to the Mach probe problem in transversely flowing strongly magnetized plasmas.

The kinetic equation governing a strongly magnetized transverse plasma flow past a convex ion-collecting object is solved numerically for arbitrary ion to electron temperature ratio $\ensuremath{\tau}$. The approximation of isothermal ions adopted in a recent fluid treatment of the same plasma model [I. H. Hutchinson, Phys. Rev. Lett. 101, 035004 (2008)] is shown to have no more than a small quantitative effect on the solution. In particular, the ion flux density to an elementary portion of the object still only depends on the local surface orientation. We rigorously show that the solution can be condensed in a single ``calibration factor'' ${M}_{c}$, function of $\ensuremath{\tau}$ only, enabling Mach probe measurements of parallel and perpendicular flows by probing flux ratios at two different angles in the plane of flow and magnetic field.
Ethical Issues in Big Data Health Research: Currents in Contemporary Bioethics

Mark A. Rothstein Let me say at the outset that I am not an expert on Big Data. I am not even an expert on Little Data. I am, like many of you, someone who teaches and writes about research ethics, including privacy, autonomy, and informed consent. I am someone who is concerned whenever I hear that a new research method is so exciting and so promising that we ought to set aside the ethical principles and rules that have shaped the world of research ethics since the Nuremberg Code in 1947. I am reminded of the statement of J. Robert Oppenheimer, theoretical physicist and father of the atom bomb: “When you see something that is technically sweet, you go ahead and do it and you argue about what to do about it only after you have had your technical success.”1 I hope we do not fall into the trap of believing that any new information technology is worth using in health research regardless of the ethical issues in performing the research or the larger implications. In this article, I will cover the following issues: (1) whether traditional research regulations should apply to Big Data health research; (2) the relationship between privacy and autonomy in Big Data health research; and (3) the role of informed consent in Big Data health research.
Multilingual Debugging Support for Data-Driven and Thread-Based Parallel Languages

Current debugging support is inadequate for debugging programs written in data-driven and multithreaded parallel programming languages. Yet such languages are essential for attaining high-performance in the next generation of parallel applications, which tend to be dynamic and irregular in their structure. Also, such applications can often benefit from a multi-paradigm approach, where individual modules are programmed using different parallel paradigms to fit their computational structure. We present a methodology, and its embodiment in a debugging tool, that supports the requirements of programmers writing data-driven applications.
Equilibrium layoff as termination of a dynamic contract

In a dynamic model of the labor market with moral hazard, equilibrium layoff is modeled as termination of an optimal long-term contract. Termination, together with compensation (current and future), is used as an incentive device to induce worker efforts. I then use the model to study analytically the effects of a firing tax on termination and worker compensation and utility. There are three layers to the impact of a firing tax on layoff and worker utility. A higher firing tax could either reduce aggregate termination and increase worker utility, or increase aggregate termination and reduce worker utility, depending on the structure of the environment.
Forecasting with Real-Time Macroeconomic Data

Abstract Forecasts are only as good as the data behind them. But macroeconomic data are revised, often significantly, as time passes and new source data become available and conceptual changes are made. How is forecasting influenced by the fact that data are revised? To answer this question, we begin with the example of the index of leading economic indicators to illustrate the real-time data issues. Then we look at the data that have been developed for U.S. data revisions, called the “Real-Time Data Set for Macroeconomists” and show their basic features, illustrating the magnitude of the revisions and thus motivating their potential influence on forecasts and on forecasting models. The data set consists of a set of data vintages, where a data vintage refers to a date at which someone observes a time series of data; so the data vintage September 1974 refers to all the macroeconomic time series available to someone in September 1974. Next, we examine experiments using that data set by Stark and Croushore (2002), Journal of Macroeconomics 24, 507–531, to illustrate how the data revisions could have affected reasonable univariate forecasts. In doing so, we tackle the issues of what variables are used as “actuals” in evaluating forecasts and we examine the techniques of repeated observation forecasting, illustrate the differences in U.S. data of forecasting with real-time data as opposed to latest-available data, and examine the sensitivity to data revisions of model selection governed by various information criteria. Third, we look at the economic literature on the extent to which data revisions affect forecasts, including discussions of how forecasts differ when using first-available compared with latest-available data, whether these effects are bigger or smaller depending on whether a variable is being forecast in levels or growth rates, how much influence data revisions have on model selection and specification, and evidence on the predictive content of variables when subject to revision. Given that data are subject to revision and that data revisions influence forecasts, what should forecasters do? Optimally, forecasters should account for data revisions in developing their forecasting models. We examine various techniques for doing so, including state-space methods. The focus throughout this chapter is on papers mainly concerned with model development – trying to build a better forecasting model, especially by comparing forecasts from a new model to other models or to forecasts made in real time by private-sector or government forecasters.
Information technology, contract completeness, and buyer-supplier relationships

The theory of incomplete contracts has been used to study the relationship between buyers and suppliers following the deployment of modern information technology to facilitate coordination between them. Previous research has sought to explain anecdotal evidence from some industries on the recent reduction in the number of suppliers selected to do business with buyers, by appealing to relationship-specific costs that suppliers may incur. In contrast, this paper emphasizes the fact that information technology enables greater completeness of buyer-supplier contracts through more economical monitoring of additional dimensions of supplier performance. The number of terms included in the contract is an imperfect substitute for the number of suppliers. Based on this result, alternative conditions are identified under which increased use of information technology leads to a reduction in the number of suppliers without invoking relationship-specific costs. Conditions are also identified when increased use of information technology leads to an increase in the number of suppliers.
Weak Lensing and the Sloan Digital Sky Survey

While the strategy for the first applications of weak lensing has been to ‘go deep’ it is equally interesting to use one’s telescope time to instead ‘go wide’. The Sloan Survey (SDSS) provides a natural framework for a very wide area weak lensing survey.
Noncommutative Algebraic Equations and Noncommutative Eigenvalue Problem.

We analyze the perturbation series for the noncommutative eigenvalue problem AX=X λ, where λ is an element of a noncommutative ring, A is a matrix, and X is a column vector with entries from this ring. As a corollary, we obtain a theorem about the structure of perturbation series for Tr xr where x is a solution of a noncommutative algebraic equation (for r=1 this theorem was proved by Aschieri, Brace, Morariu, and Zumino (hep-th/0003228), and used to study the Born–Infeld Lagrangian for the gauge group U(1) k ).
Sampling first order logical particles

Approximate inference in dynamic systems is the problem of estimating the state of the system given a sequence of actions and partial observations. High precision estimation is fundamental in many applications like diagnosis, natural language processing, tracking, planning, and robotics. In this paper we present an algorithm that samples possible deterministic executions of a probabilistic sequence. The algorithm takes advantage of a compact representation (using first order logic) for actions and world states to improve the precision of its estimation. Theoretical and empirical results show that the algorithm's expected error is smaller than propositional sampling and Sequential Monte Carlo (SMC) sampling techniques.