cssi/SciSciGPT-SciSciNet huggingface dataset:
Conic multi-task classification

Traditionally, Multi-task Learning (MTL) models optimize the average of task-related objective functions, which is an intuitive approach and which we will be referring to as Average MTL. However, a more general framework, referred to as Conic MTL, can be formulated by considering conic combinations of the objective functions instead; in this framework, Average MTL arises as a special case, when all combination coefficients equal 1. Although the advantage of Conic MTL over Average MTL has been shown experimentally in previous works, no theoretical justification has been provided to date. In this paper, we derive a generalization bound for the Conic MTL method, and demonstrate that the tightest bound is not necessarily achieved, when all combination coefficients equal 1; hence, Average MTL may not always be the optimal choice, and it is important to consider Conic MTL. As a byproduct of the generalization bound, it also theoretically explains the good experimental results of previous relevant works. Finally, we propose a new Conic MTL model, whose conic combination coefficients minimize the generalization bound, instead of choosing them heuristically as has been done in previous methods. The rationale and advantage of our model is demonstrated and verified via a series of experiments by comparing with several other methods.
Modeling and Control of Automatic Vehicle Steering System Using Microprocessors

Abstract This paper presents the initial results of a research on development of an automatic steering system for vehicles. The objective is to reduce the driver's role as being the only commander and controller of a vehicle for traffic surveillance and safety, especially for cases like drunk drivers. A nonlinear model for a rotary steering system is developed and reduced to a linear model. The reduced model is used to design a regulator for the steering system. Since position is the only available measurement, an optimum observer based on the dual system is designed. The results are implemented on a microprocessor. The required software and hardware are presented. The results of the model combined with the regulator are compared with the experimental data.
Rotor Wake Development During the First Revolution

The wake behind a two-bladed model rotor in light climb was measured using particle image velocimetry, with particular emphasis on the development of the trailing vortex during the first revolution of the rotor. The distribution of vorticity was distinguished from the slightly elliptical swirl pattern. Peculiar dynamics within the void region may explain why the peak vorticity appeared to shift away from the center as the vortex aged, suggesting the onset of instability. The swirl and axial velocities (which reached 44 and 12 percent of the rotor-tip speed, respectively) were found to be asymmetric relative to the vortex center. In particular, the axial flow was composed of two concentrated zones moving in opposite directions. The radial distribution of the circulation rapidly increased in magnitude until reaching a point just beyond the core radius, after which the rate of growth decreased significantly. The core-radius circulation increased slightly with wake age, but the large-radius circulation appeared to remain relatively constant. The radial distributions of swirl velocity and vorticity exhibit self-similar behaviors, especially within the core. The diameter of the vortex core was initially about 10 percent of the rotor-blade chord, but more than doubled its size after one revolution of the rotor. According to vortex models that approximate the measured data, the core-radius circulation was about 79 percent of the large-radius circulation, and the large-radius circulation was about 67 percent of the maximum bound circulation on the rotor blade. On average, about 53 percent of the maximum bound circulation resides within the vortex core during the first revolution of the rotor.
Reparations and the Colonial Dilemma: The Insurmountable Hurdles and Yet Transformative Benefits

The Seventh Annual Latina and Latino Critical Race Theory ("LatCrit") Conference held in May 2002 at the University of Oregon, not unlike other efforts in the movement, addressed a panoply of challenging, provocative, and controversial issues. Perhaps one the most intellectually interesting and yet troubling panels addressed reparations for the inhabitants of United States' colonial territories. Specifically, the panel was titled "Reparations, Redress, and Remedies: Undoing the Legacy of Colonialism and Imperialism." Members of the academy as well as a representative of Puerto Rico's Independence Party participated in a lively discussion and debate. Although the articles resulting from this panel touch upon Puerto Rico's colonial dilemma, not all addressed the issue of reparations. It is the topic of reparations that is the focus of this cluster introduction. The topic of reparations provokes strong feelings because, among other reasons, it is a request of the dominant culture to atone for past wrongs, primarily through monetary relief. For many, the response to any request for reparations, but particularly for a request from the inhabitants of Puerto Rico, would be: "Why reparations?" Not unlike reparations claims for Native Hawaiians, opponents to a Puerto Rican reparations effort would probably deem the reparations claims unavailing because the opponents simply would fail to perceive that any legal wrong has occurred. This cluster introduction will address this question of "why reparations." Before addressing the nascent Puerto Rican reparations debate, a brief description of LatCrit theory is in order.
A Competitive Theory of Equilibrium Mismatch

This paper studies labor-market mismatch, or the coexistence of unemployment and vacancies, in a competitive market equilibrium in which jobs are assigned to heterogeneous workers, an assignment model. Jobs are assigned under uncertain and sequential trade hence a "worker-job" match only takes place in markets where trade takes place. This gives rise to a competitive market equilibrium with unemployed workers and vacant jobs as equilibrium assignments to markets where trade is expected but not realized. The first and second welfare theorems hold and the assignment can be decentralized through contingent wages that 'seem rigid.' The model is integrated with a typical real business cycle model and with models of equilibrium search unemployment. In response to neutral productivity shocks, the model produces a Beveridge curve --a negative co-movement between unemployment and vacancies during the business cycle.
Verifying Uniqueness in a Logical Framework

We present an algorithm for verifying that some specified arguments of an inductively defined relation in a dependently typed λ-calculus are uniquely determined by some other arguments. We prove it correct and also show how to exploit this uniqueness information in coverage checking, which allows us to verify that a definition of a function or relation covers all possible cases. In combination, the two algorithms significantly extend the power of the meta-reasoning facilities of the Twelf implementation of LF.
Distributed priority inheritance for real-time and embedded systems

We study the problem of priority inversion in distributed real-time and embedded systems and propose a solution based on a distributed version of the priority inheritance protocol (PIP). Previous approaches to priority inversions in distributed systems use variations of the priority ceiling protocol (PCP), originally designed for centralized systems as a modification of PIP that also prevents deadlock. PCP, however, requires maintaining a global view of the acquired resources, which in distributed systems leads to high communication overhead. This paper presents a distributed PIP built on top of a deadlock avoidance schema that requires much less communication than PCP. Since the system is already deadlock free and priority inversions can be detected locally, we obtain an efficient dynamic resource allocation system that prevents deadlocks and handles priority inversions.
KELVIN–HELMHOLTZ STABILITY AND TWO–PHASE FLOW

Abstract The ill-posedness of the two-phase flow problems is explicitly related to the Kelvin-Helmholtz instability of two compressible fluid layers. A long wavelength formulation of the Kelvin-Helmholtz problem is derived. Various features of this formulation are explored briefly.
A risk comparison of ordinary least squares vs ridge regression

We compare the risk of ridge regression to a simple variant of ordinary least squares, in which one simply projects the data onto a finite dimensional subspace (as specified by a principal component analysis) and then performs an ordinary (un-regularized) least squares regression in this subspace. This note shows that the risk of this ordinary least squares method (PCA-OLS) is within a constant factor (namely 4) of the risk of ridge regression (RR).
A Network Model of Market Prices and Trading Volume

This paper presents a network model of market prices and trading volume. In the model individual agents are represented by nodes. If any two nodes trade with each other within a unit of calendar time, they are considered connected by an edge. The edges deÞne a network topology. I assume that the price difference between any two nodes is a random variable drawn from a normal distribution with a mean proportional to the number of edges between them and a constant variance. I deÞne trading volume as the number of new edges added to the network per unit of calendar time. I show that depending on the underlying pattern of interaction, different levels of volume lead to the same changes in prices. I also show that while the agents do not directly observe the global pattern of interaction, they are able to consistently estimate it. I argue that an appropriate empirical price-volume model is a system of simultaneous equations in which the variance of prices is a function of volume and volume is a function of price variability and characteristics of the network topology. ∗Please do not quote or circulate without an explicit permission from the author. The views expressed in the paper are my own and do not necessarily constitute an official position of the International Monetary Fund. Contact: International Capital Markets Department, International Monetary Fund, Washington, DC 20431. Phone: (202) 623-5642, Fax: (202) 623-5692, E-mail: akirilenko@imf.org.
Bridging the Workforce Gap for Our Aging Society: How to Increase and Improve Knowledge and Training. Report of an Expert Panel

The healthcare workforce is currently unprepared for the increasing number of older persons and the complexities of their healthcare needs. Too few healthcare workers are adequately trained in geriatrics, and developers of educational curricula across healthcare disciplines have been slow to incorporate or require geriatric training. In April 2003, leaders in geriatrics met in Washington, D.C., to discuss and recommend solutions to the growing shortage of an appropriately trained workforce for geriatric research, education, and patient care. After considering data, presenting statistics, and offering insights into the future, the conference concluded by formulating recommendations to meet specific challenges. This report is a summary of the conference proceedings and recommendations, and it serves as a reminder that demographic trends and an everexpanding geriatric knowledge base demand not only attention, but also action.
How Graphic Visual Health Warnings Affect Young Smokers' Thoughts of Quitting

Two-thirds of adolescent and young adult smokers become lifetime smokers, and one-half of those lifetime smokers will die from this habit. The authors examine alternative persuasive pathways to thoughts of quitting taken by adolescent and young adult smokers when exposed to graphic visual health warnings on cigarette packages. For adolescent smokers, the authors find that graphic warnings and smoking frequency affect fear, and fear influences negative health beliefs about smoking, ultimately increasing thoughts of quitting. They also find that the graphic warning and a graphic warning × smoking frequency interaction have incremental effects on quit thoughts beyond the effects of fear and negative health beliefs. Using a longitudinal design with a sample of young adult smokers, the authors find support for many of the adolescent smoker findings, particularly the incremental effects of graphicness and its interaction with smoking frequency. These similar results from diverse samples support the use of graph...
Political Budget Cycles: Evidence from Italian Cities

The introduction of a new real estate taxes in Italy in 2011 provides a natural experiment, which is useful to test for political budget cycles. The new real estate tax allowed discretion to local governments. This generates a random variation in the distance of municipalities from the following elections when they choose the level of the tax rate. We do find substantial evidence of political budget cycles, with municipalities choosing lower tax rates when close to elections. We observe this budget cycle for smaller municipalities where the tax was more likely to be the single most important issue for the local government. Cities close to elections with large deficits did not set lower rates and so did municipalities with a lower average value of properties. Finally, the political budget cycle is stronger in the South.
Double ridges on Europa accommodate some of the missing surface contraction

Crosscutting relationships of tectonic lineaments on Europa record the history of surface deformation. We mapped the displacement and orientation of older features crosscut by two types of lineaments: bands and double ridges. These measurements allow us to determine both the strike-perpendicular and strike-parallel displacement along investigated features. Double ridges record both ridge-perpendicular contraction and expansion, with a mean of 0.16 ± 0.06 km (needs space) of contraction based on the analysis of 16 double ridges. Bands record expansion, with a mean of 3.33 ± 0.27 km for the six bands analyzed, but with perpendicular displacement less than their apparent morphologic widths of 3–24 km. The implied global surface strain for double ridges (including those that expand) and bands is 2.22 ± 0.76% contraction and 7.60 ± 3.7% expansion, respectively. Double ridges thus may accommodate part of the surface expansion recorded by bands. Most current models for double ridges do not predict contraction. The models that satisfy the observations for bands are “slow-spreading” models, cryovolcanism, and folding.
Fuzzy Frontiers of Production: Evidence of Persistent Inefficiency, in Safety Expenditures

This study documents a strong inverse relationship between accident rates and production in a sample of eleven firms in the same narrowly defined industry classification. Given the detailed set of input controls and controls for plant-specific and time-specific factors used in the analysis, the study argues that a theoretical framework that describes firms as operating on well-defined production frontiers is not adequate for providing an entirely accurate interpretation of the basic empirical finding.Three elaborations to the basic production frontier framework are developed and used to interpret the accident-productivity relationship.
Effectiveness of Reading and Mathematics Software Products: Findings from the First Student Cohort

Congress posed questions about the effectiveness of educational technology and how effectiveness is related to conditions and practices. The study identified reading and mathematics software products based on prior evidence of effectiveness and other criteria and recruited districts, schools, and teachers to implement the products. On average, after one year, products did not increase or decrease test scores by amounts that were statistically different from zero. For first and fourth grade reading products, the study found several school and classroom characteristics that were correlated with effectiveness, including student-teacher ratios (for first grade) and the amount of time products were used (for fourth grade). The study did not find characteristics related to effectiveness for sixth grade math or algebra. The study also found that products caused teachers to be less likely to lecture and more likely to facilitate, while students using reading or mathematics software products were more likely to be working on their own. The results reported here are based on schools and teachers who were not using the products in the previous school year. Whether products are more effective when teachers have more experience using them is being examined with a second year of data. The study will involve teachers who were in the first data collection (those who are teaching in the same school and at the same grade level or subject area) and a new group of students. The second-year study will also report results separately for the various products.
A Consistent Histogram Estimator for Exchangeable Graph Models

Exchangeable graph models (ExGM) subsume a number of popular network models. The mathematical object that characterizes an ExGM is termed a graphon. Finding scalable estimators of graphons, provably consistent, remains an open issue. In this paper, we propose a histogram estimator of a graphon that is provably consistent and numerically efficient. The proposed estimator is based on a sorting-and-smoothing (SAS) algorithm, which first sorts the empirical degree of a graph, then smooths the sorted graph using total variation minimization. The consistency of the SAS algorithm is proved by leveraging sparsity concepts from compressed sensing.
Waiting to Persuade

I analyze a sequential bargaining model in which players are optimistic about their bargaining power (measured as the probability of making offers), but learn as they play the game. I show that there exists a uniquely predetermined settlement date, such that in equilibrium the players always reach an agreement at that date, but never reach one before it. Given any discount rate, if the learning is sufficiently slow, the players agree immediately. I show that, for any speed of learning, the agreement is delayed arbitrarily long, provided that the players are sufficiently patient. Therefore, although excessive optimism alone cannot cause delay, it can cause long delays if the players are expected to learn.
Generic integral manifolds for weight two period domains

We define the notion of a generic integral element for the Griffiths distribution on a weight two period domain, draw the analogy with the classical contact distribution, and then show how to explicitly construct an infinite-dimensional family of integral manifolds tangent to a given element.
Partition Based Path Join Algorithms for XML Data

Path expression is an important component in querying XML data. The extended preorder numbering scheme enables us to quickly determine the ancestor-descendant relationship between elements in the hierarchy of XML data. Using the numbering scheme, a path expression can be evaluated by join operations to avoid potentially high cost of tree traversals. In this paper, we first formulate XML path queries as range-point join queries. Then we discuss the partition based algorithms that can utilize the range containment property to efficiently process the range-point join queries. Under the partition based framework, we propose three algorithms, namely Descendant partition join, Segment-tree partition join and Ancestor Link partition join, which can be chosen by a query optimizer for different input data characteristics. The experimental results show that the partition based algorithms can make better use of the buffer memory than sort-merge algorithms, and the proposed Ancestor Link join algorithm yields the best performance by using small in-memory data structures and by taking advantage of unevenly sized inputs.
The external effects of place-based subsidized housing

Abstract Prior research has provided little evidence that subsidized housing investments generate significant external benefits to their neighborhoods. This paper revisits the external effects of subsidized housing, exploring the case of New York City. Relying on geocoded administrative data, we estimate a difference-in-difference specification of a hedonic regression model. We find significant and sustained external benefits. Spillovers increase with project size, and decrease with distance from the project sites and with the proportion of units in multifamily, rental buildings. Our results are robust to alternative specifications. Some of the benefit appears due to the effect of the replacement of existing disamenity.
Does state preschool crowd-out private provision? The impact of universal preschool on the childcare sector in Oklahoma and Georgia

Universal preschool policies introduced in Georgia and Oklahoma offer an opportunity to investigate the impact of government intervention on provision of childcare. Since Georgia used a voucher-like program and Oklahoma utilized its existing public schools, the two states offer a case study of how government provision compares to government subsidization alone. Using a synthetic control group difference-in-difference estimation framework, we examine the effects of universal preschool on childcare providers. In both states there is an increase in the number of formal childcare centers. With the voucher-like program in Georgia, the overall increase in care is partly driven by an increase in the supply of formal childcare in the private sector and partly driven by new publicly-provided preschools. However, there is substantial crowd-out of private consumption of preschool. In Oklahoma, where universal preschool is publicly provided, the increase in the number of childcare providers occurred only in the public sector. The expansion of publicly-provided care seems to be driven largely by movement of employees from private centers to public settings. As such, this case-study comparison suggests that government subsidization through funding was more effective at expanding preschool than government provision.
Petroleum product pricing and complementary policies: experience of 65 developing countries since 2009

Unable to cope fully with steadily climbing world oil prices since mid-2009, many of the 65 countries reviewed in this paper have progressed slowly or even reversed course in reforming pricing of petroleum products. End-user prices in July 2012 varied by two orders of magnitude across the countries. More than two-fifths, including some that had only recently adopted automatic pricing mechanisms, froze the prices of gasoline, diesel, or both for months or even years on end during the study period. When the prices were finally adjusted, the increases were sometimes substantial, leading to large-scale protests, partial or full reversals of price adjustments, or softening of pricing reform policy. Governments' attempts to keep domestic prices artificially low -- through price control, export or quantity restrictions, or political pressure put on oil companies -- have helped curb inflation in the short term, but frequently with serious negative consequences: flourishing black markets, smuggling, fuel adulteration, illegal diversion of subsidy funds, large financial losses suffered by fuel suppliers, deteriorating refining and other infrastructure, and acute fuel shortages causing economy-wide damage. In several countries, subsidies, price controls, and other restrictions have helped protect inefficient refineries and oil marketers. Mitigation responses have included fuel conservation programs; fuel diversification, particularly liquid biofuels to substitute gasoline and diesel; and efforts to lower costs of supply, including strengthening infrastructure, promoting price competition, hedging, negotiating price discounts with exporters, and bulk procurement. Various forms of assistance to consumers have also been offered, especially to households, agriculture, transport, and fisheries.
Computational efficiency and practical implications for a client grid

Client grid computing models based on participation of non-dedicated clients have been popular for computationally intensive tasks. Two fundamental requirements of these models are efficiency and accuracy. Common implementations use 1) checkpointing mechanisms for higher efficiency and 2) redundancy to achieve accurate results. In this paper, we formulate client grid computation using stochastic models and analyze the effects of checkpointing and redundancy in relation to performance. We first quantify the computation times required for a task with and without checkpointing, then the relationship between result accuracy and redundancy. Finally, we give a sensitivity analysis for parameters relating to client availability, checkpointing, and redundancy to provide guidelines on design and implementation of client grid systems.
Observation of the Kapitza–Dirac effect

In their famous 1927 experiment, Davisson and Germer observed the diffraction of electrons by a periodic material structure, so showing that electrons can behave like waves. Shortly afterwards, Kapitza and Dirac predicted that electrons should also be diffracted by a standing light wave. This Kapitza-Dirac effect is analogous to the diffraction of light by a grating, but with the roles of the wave and matter reversed. The electron and the light grating interact extremely weakly, via the 'ponderomotive potential', so attempts to measure the Kapitza-Dirac effect had to wait for the development of the laser. The idea that the underlying interaction with light is resonantly enhanced for electrons in an atom led to the observation that atoms could be diffracted by a standing wave of light. Deflection of electrons by high-intensity laser light, which is also a consequence of the Kapitza-Dirac effect, has also been demonstrated. But the coherent interference that characterizes wave diffraction has not hitherto been observed. Here we report the diffraction of free electrons from a standing light wave-a realization of the Kapitza-Dirac effect as originally proposed.
Innovative Firms in Emerging Market Countries

PART I: THE THEORETICAL AND EMPIRICAL CONTEXT 1. Innovative Firms in Emerging Market Countries: An Introduction 2. Building Innovative Capabilities in Latecomer Emerging Market Firms: Some Key Issues PART II: INNOVATIVE FIRMS IN EMERGING MARKETS: COUNTRY EXPERIENCES ASIA 3. China 4. India 5. Malaysia 6. South Korea and Taiwan LATIN AMERICA 7. Brazil 8. Argentina PART III: COMPARATIVE CONCLUSIONS 9. Conclusions
Triggers of contract breach : contract design, shocks, or institutions ?

This paper constructs a large contract-level data set to examine factors that trigger breach of foreign investment contracts. Similar to the case of outright expropriation, political regime type is an important determinant of breach of contract. Furthermore, although investors' bargaining power becomes obsolete as contracts mature, contracts can be designed to mitigate the risk of breach of contract by involving multilateral organizations and creating buffers to absorb commodity price shocks. The paper examines the type of countries prone to contract breaches. After controlling for regional and sector fixed effects, less-democratic and resource-dependent governments are more likely to breach contracts, especially after large global shocks, notably natural disasters.
GEOMETRIC MORPHOLOGY OF GRANULAR MATERIALS

We present a new method to transform the spectral pixel information of a micrograph into an affine geometric description, which allows us to analyze the morphology of granular materials. We use spectral and pulse-coupled neural network based segmentation techniques to generate blobs, and a newly developed algorithm to extract dilated contours. A constrained Delaunay tessellation of the contour points results in a triangular mesh. This mesh is the basic ingredient of the Chodal Axis Transform, which provides a morphological decomposition of shapes. Such decomposition allows for grain separation and the efficient computation of the statistical features of granular materials.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Polytopes with Preassigned Automorphism Groups

We prove that every finite group is the automorphism group of a finite abstract polytope isomorphic to a face-to-face tessellation of a sphere by topological copies of convex polytopes. We also show that this abstract polytope may be realized as a convex polytope.
Magnetosonic wave excitation by ion ring distributions in the Earth's inner magnetosphere

Combining Time History of Events and Macroscale Interaction during Substorms (THEMIS) wave and particle observations and a quantitative calculation of linear wave growth rate, we demonstrate that magnetosonic (MS) waves can be locally excited by ion ring distributions in the Earth's magnetosphere when the ion ring energy is comparable to the local Alfven energy. MS waves in association with ion ring distributions were observed by THEMIS A on 24 November 2010 in the afternoon sector, both outside the plasmapause where the wave spectrum varied with fLHR and inside the plasmapause where the wave frequency band remained nearly constant. Our plasma instability analysis in three different regions shows that higher and narrow frequency band MS waves are excited locally outside the plasmapause, and lower and broad frequency band MS waves are excited in the region where the density slightly increases. However, there is no evidence for wave excitation inside the plasmapause, and wave propagation from a distant source is needed to explain their existence. The simulation of the MS wave growth rate spectra during this event agrees reasonably well with the observed wave magnetic field power spectra. We also simulated a MS wave event on 19 October 2011 in the dusk sector and found that the ion ring distribution with an ion ring energy slightly higher than the local Alfven energy can excite the typical broad band MS waves outside the plasmapause.
Towards a virtual teaching assistant to answer questions asked by students in introductory computer science

Students in introductory programming classes often articulate their questions and information needs incompletely. Consequently, the automatic classification of student questions to provide automated tutorial responses is a challenging problem. This dissertation analyzes 411 questions from an introductory Java programming course by reducing the natural language of the questions to a vector space, and then utilizing cosine similarity to identify similar previous questions. I report classification accuracies between 23% and 56%, obtaining substantial improvements by exploiting domain knowledge (compiler error messages) and educational context (assignment name). My results are especially timely and relevant for online courses where students are completing the same set of assignments asynchronously and access to staff is limited.
Transaction Cost Economics: How It Works; Where It is Headed

This paper begins with a sketch of the New Institutional Economics, with special emphasis on the ‘institutional environment’ (North and others) and the ‘institutions of governance’ (Coase and others). Thereafter the paper mainly emphasizes the applications of transaction cost economics to the study of governance, the object being to effect an economizing alignment between transactions, which differ in their attributes, and governance structures (firms, markets, hybrids, bureaus), which differ in their cost and competence. I raise a series of issues – phenomena of interest, describing human agents, describing firms, purposes served, scaling up – to which any would-be theory of the firm should be expected to speak and indicate how transaction cost economics responds to each. I thereafter describe the mechanisms through which transaction cost economics is implemented and develop some of the core conceptual supports out of which it works. Applications to public bureaus, strategic management, and intractable transactions are sketched.
Informal tradables and the employment growth of Indian manufacturing

India's manufacturing growth from 1989 to 2010 displays two intriguing properties: 1) a substantial fraction of absolute and net employment growth is concentrated in informal tradable industries, and 2) much of this growth is connected to the development of one-person establishments. This paper investigates the causes and determinants of these growth patterns. The rapid urbanization of the informal sector plays the strongest role, while there is some evidence for subcontracting by the formal sector and a "push" entrepreneurship story. The paper also finds modest connections of this growth to rising female labor force participation. The connection between the presence of informal manufacturing and local productivity levels is strong, and varies across urban and rural areas in ways that bolster urbanization and subcontracting hypotheses.
Planets in Binary Star Systems

Disks Around Young Binary Stars.- Probing the Impact of Stellar Duplicity on Planet Occurrence with Spectroscopic and Imaging Observations.- The Detection of Extrasolar Planets Using Precise Stellar Radial Velocities.- Observational Techniques for Detecting Planets in Binary Systems.- The SARG Planet Search.- Early Evolution of Planets in Binaries: Planet-Disk Interaction.- Dynamics and Planet Formation in/Around Binaries.- Gravitational Instability in Binary Protoplanetary Disks.- N-Body Integrators for Planets in Binary Star Systems.- Terrestrial Planet Formation in Binary Star Systems.- Planetary Dynamics and Habitable Planet Formation in Binary Star Systems.
Extending Task Parallelism For Frequent Pattern Mining

We thank Melanie Dybvig for her help in improving the quality of this paper. Our work was supported by IBM, King Abdullah University of Science and Technology (KAUST), National Science Foundation grants EIA-0202048 and CCF-0541335, and a grant from the Lilly Endowment.
A Primer on Piecewise Parabolic Multiple Regression Analysis via Estimations of Chicago CBD Land Prices

This article proposes a non-parametric method for estimating spatial price functions. Space is divided into squares. The independent variables are barycentric coordinates that uniquely describe the location of observations in space. The regression coefficients are estimates of the height of the function directly over the vertices of the square spatial units. Within each square the function has hyperbolic iso-price curves and parabolic sections. The price function is continuous, but not differentiable, at the boundaries between contiguous squares. This method is applied to the problem of describing the price per front foot of land in the Chicago CBD. A rather complex price surface is revealed that would be difficult to estimate using other methodologies but was easily estimated by this simple method.
Automorphic Forms and Representations

1. Modular forms 2. Automorphic forms and representations of GL( 2, R) 3. Automorphic representations 4. GL(2) over a p-adic field.
Entry costs, industry structure, and cross-country income and TFP differences

Abstract Entry costs vary dramatically across countries. To assess their impact on cross-country differences in output and TFP, we construct a model with endogenous entry and operation decisions by firms. We calibrate the model to match the U.S. distribution of employment and firms by size. Higher entry costs lead to greater misallocation of productive factors and lower TFP and output. In the model, countries in the lowest decile of the entry costs distribution have 1.32 to 1.45 times higher TFP and 1.52 to 1.75 times higher output per worker than countries in the highest decile. As in the data, higher entry costs are associated with lower entry rates and business density.
Fracture of thin sections containing through and part-through cracks

Fracture mechanics theory used to determine effects of crack dimensions and material properties on fracture stresses for thin metal sections with through and part-through cracks
Arbitrator Liability: Reconciling Arbitration and Mandatory Rules

In this Article, Professor Guzman resolves the tension that exists between mandatory legal rules and the widespread use of arbitration. In recent years, U.S. courts have expanded the range of enforceable arbitration agreements to include agreements that cover areas of law previously thought to be within the exclusive domain of courts. Among the disputes that are now deemed arbitrable are those that implicate mandatory rules such as securities and antitrust laws. Under current law, the willingness of courts to enforce arbitration agreements and to uphold the resulting arbitral awards with minimal judicial review makes it possible for the parties to a transaction to avoid mandatory rules of law. Until now, it has generally been believed that the legal system must either restrict the use of arbitration or permit arbitration and accept that doing so turns all mandatory rules into default rules. This Article proposes a mechanism that permits the continued use of arbitration without abandoning the mandatory nature of legal rules. The recommended approach, called “arbitrator liability,” allows the losing party in an arbitration to sue the arbitrator on the ground that a mandatory rule was ignored. Under existing legal rules, arbitrators have an incentive to ignore mandatory rules of law in favor of the contractual terms agreed to by the parties. Arbitrator liability gives arbitrators an incentive to apply mandatory rules of law. Giving proper incentives to arbitrators will ensure that mandatory † Boalt Hall School of Law, University of California at Berkeley. I owe thanks to Richard Brooks, Richard Buxbaum, David Caron, Stephen Choi, Robert Cooter, Jesse Fried, Stephen Ware, David Wilkins, and John Yoo, as well as participants at both the 1999 Friedmann Conference on International Securities Regulation and Antitrust and the Latin American Law and Economics Association 1999 Annual Meetings for helpful comments and discussions. Special thanks to Nicholas James and Jeannie Sears. Melissa Kennedy, Philip Tendler, and Ryan Waterman provided invaluable research assistance. GUZMAN TO PRINTER (FINAL).DOC 09/21/00 12:59 PM 1280 DUKE LAW JOURNAL [Vol. 49:1279 rules are enforced, thereby eliminating the incentive for the parties to draft arbitration agreements intended to avoid those rules. The benefits of arbitration can be retained without sacrificing the ability of lawmakers to adopt mandatory rules.
PPML estimation of dynamic discrete choice models with aggregate shocks

This paper introduces a computationally efficient method for estimating structural parameters of dynamic discrete choice models with large choice sets. The method is based on Poisson pseudo maximum likelihood (PPML) regression, which is widely used in the international trade and migration literature to estimate the gravity equation. Unlike most of the existing methods in the literature, it does not require strong parametric assumptions on agents' expectations, thus it can accommodate macroeconomic and policy shocks. The regression requires count data as opposed to choice probabilities; therefore it can handle sparse decision transition matrices caused by small sample sizes. As an example application, the paper estimates sectoral worker mobility in the United States.
Pros and Cons of Linking Trade and Labor Standards

Abstract This chapter addresses the debate over whether labor standards should be linked to trade policy, by being included in the World Trade Organization and becoming subject to trade sanctions. We first put the debate into context by reviewing the issues and the events that have prompted it. We next turn to the arguments in favor of putting labor standards into the WTO, then address the arguments against this. Finally we offer advice to developing countries regarding the position that they should take, and how more broadly they should deal with this and other issues in multilateral trade negotiations.
High-Level Fault Modeling in Surface-Micromachined MEMS

MEMS structures rendered defective by particles are modeled at the schematic-level using existing models of fault-free MEMS primitives within the nodal simulator NODAS. We have compared the results of schematic-level fault simulations with low-level finite element analysis (FEA) and demonstrated the efficacy of such an approach. Analysis shows that NODAS achieves a 60X speedup over FEA with little accuracy loss in modeling defects caused by particles.
Kinematics and Dark Energy from Supernovae at z > 1

We have discovered 16 Type Ia supernovae (SNe Ia) with the Hubble Space Telescope (HST) and have used them to provide the first conclusive evidence for cosmic deceleration that preceded the current epoch of cosmic acceleration. Joint constraints on both the recent equation of state of dark energy, w 0, and its time evolution, dw/dz, are a factor of ∼ 8 more precise than its first estimate and twice as precise as those without the SNe Ia discovered with HST. Our constraints are consistent with the static nature of and value of w expected for a cosmological constant (i.e., w 0 = −1.0, dw/dz = 0), and are inconsistent with very rapid evolution of dark energy.
Hamiltonian Derivation of a Detailed Fluctuation Theorem

We analyze the microscopic evolution of a system undergoing a far-from-equilibrium thermodynamic process. Explicitly accounting for the degrees of freedom of participating heat reservoirs, we derive a hybrid result, similar in form to both the fluctuation theorem and a statement of detailed balance. We relate this result to the steady-state fluctuation theorem and to a free energy relation valid far from equilibrium.
Toric residue and combinatorial degree

Consider an n-dimensional projective toric variety X defined by a convex lattice polytope P. David Cox introduced the toric residue map given by a collection of n + 1 divisors (Z 0 , ..., Z n ) on X. In the case when the Z i are T-invariant divisors whose sum is X \ T, the toric residue map is the multiplication by an integer number. We show that this number is the degree of a certain map from the boundary of the polytope P to the boundary of a simplex. This degree can be computed combinatorially. We also study radical monomial ideals I of the homogeneous coordinate ring of X. We give a necessary and sufficient condition for a homogeneous polynomial of semiample degree to belong to I in terms of geometry of toric varieties and combinatorics of fans. Both results have applications to the problem of constructing an element of residue one for semiample degrees.
Bounds upon Graviton mass, and making use of the difference between Graviton propagation speed and HFGW transit speed to observe post Newtonian corrections to Gravitational potential fields

The author presents a post Newtonian approximation based upon an earlier argument / paper by Clifford Will as to Yukawa revisions of gravitational potentials in part initiated by gravitons with explicit mass dependence in their Compton wave length. Prior work with Clifford Will’s idea was stymied by the application to binary stars and other such astro-physical objects with non useful frequencies topping off as up to 100 Hertz, thereby rendering Yukawa modifications of Gravity due to gravitons effectively an experimental curiosity which was not testable with any known physics equipment.
Twisted analytic torsion and adiabatic limits

We study an analogue of the analytic torsion for elliptic complexes that are graded by $\mathbb{Z}_2$, orignally constructed by Mathai and Wu. Motivated by topological T-duality, Bouwknegt an Mathai study the complex of forms on an odd-dimensional manifold equipped with with the twisted differential $d_H = d+H$, where $H$ is a closed odd-dimensional form. We show that the Ray-Singer metric on this twisted determinant is equal to the untwisted Ray-Singer metric when the determinant lines are identified using a canonical isomorphism. We also study another analytical invariant of the twisted differential, the derived Euler characteristic $\chi'(d_H)$, as defined by Bismut and Zhang.
Convergent sequences of sparse graphs: A large deviations approach

Models based on sparse graphs are of interest to many communities: they appear as basic models in combinatorics, probability theory, optimization, statistical physics, information theory, and more applied fields of social sciences and economics. Different notions of similarity (and hence convergence) of sparse graphs are of interest in different communities. In probability theory and combinatorics, the notion of Benjamini-Schramm convergence, also known as left-convergence, is used quite frequently. Statistical physicists are interested in the the existence of the thermodynamic limit of free energies, which leads naturally to the notion of right-convergence. Combinatorial optimization problems naturally lead to so-called partition convergence, which relates to the convergence of optimal values of a variety of constraint satisfaction problems. The relationship between these different notions of similarity and convergence is, however, poorly understood. In this paper we introduce a new notion of convergence of sparse graphs, which we call Large Deviations or LD-convergence, and which is based on the theory of large deviations. The notion is introduced by “decorating” the nodes of the graph with random uniform i.i.d. weights and constructing corresponding random measures on [0,1] and [0,1]2. A graph sequence is defined to be converging if the corresponding sequence of random measures satisfies the Large Deviations Principle with respect to the topology of weak convergence on bounded measures on [0,1]d,d=1,2. The corresponding large deviations rate function can be interpreted as the limit object of the sparse graph sequence. In particular, we can express the limiting free energies in terms of this limit object. We then establish that LD-convergence implies the other three notions of convergence discussed above, and at the same time establish several previously unknown relationships between the other notions of convergence. In particular, we show that partition-convergence does not imply left- or right-convergence, and that right-convergence does not imply partition-convergence. © 2016 Wiley Periodicals, Inc. Random Struct. Alg., 2016
Firm-specific cost savings and market power

We report a policy experiment that illustrates a potential problem of using historical pass-through rates as a means of predicting the competitive consequences of projected firm-specific cost savings in antitrust contexts, particularly in merger analysis. The effects of cost savings on welfare can vary vastly, depending on how the savings affect the industry supply schedule. In a capacity-constrained price-setting oligopoly, we observe that cost savings can overwhelm behaviorally salient market power incentives when the savings affect marginal (high cost) units. However, cost savings of the same magnitude on an infra-marginal unit leave market power unchanged.
One-pot synthesis of GABA amides via the nucleophilic addition of amines to 3,3-disubstituted cyclopropenes

A one-pot synthesis of various GABA amides has been demostrated, employing the nucleophilic addition of primary and secondary amines across the double bond of cyclopropene-3-carboxamides, followed by ring-opening of the resulting donor–acceptor cyclopropanes and subsequent in situ reduction of enamine (imine) intermediates.