cssi/SciSciGPT-SciSciNet huggingface dataset:
Doppler synthetic aperture radar interferometry: a novel SAR interferometry for height mapping using ultra-narrowband waveforms

This paper introduces a new and novel radar interferometry based on Doppler synthetic aperture radar (Doppler-SAR) paradigm. Conventional SAR interferometry relies on wideband transmitted waveforms to obtain high range resolution. Topography of a surface is directly related to the range difference between two antennas configured at different positions. Doppler-SAR is a novel imaging modality that uses ultra-narrowband continuous waves (UNCW). It takes advantage of high resolution Doppler information provided by UNCWs to form high resolution SAR images. We introduce the theory of Doppler-SAR interferometry. We derive an interferometric phase model and develop the equations of height mapping. Unlike conventional SAR interferometry, we show that the topography of a scene is related to the difference in Doppler frequency between two antennas configured at different velocities. While the conventional SAR interferometry uses range, Doppler and Doppler due to interferometric phase in height mapping; Doppler-SAR interferometry uses Doppler, Doppler-rate and Doppler-rate due to interferometric phase in height mapping. We demonstrate our theory in numerical simulations. Doppler-SAR interferometry offers the advantages of long-range, robust, environmentally friendly operations; low-power, low-cost, lightweight systems suitable for low-payload platforms, such as micro-satellites; and passive applications using sources of opportunity transmitting UNCW.
Three-dimensional SCFT from M2-branes at conifold singularities

Recently, it was conjectured that parallel branes at conical singularities are related to string/M theory on AdS × X where X is an Einstein manifold. In this paper we consider coincident M2 branes near a conifold singularity when M theory is compactified on AdS4 × Q1,1,1, where Q1,1,1 = (SU(2) × SU(2) × SU(2))/(U(1) × U(1)) is a seven dimensional Sasaki-Einstein manifold. We argue that M theory on AdS4 × Q1,1,1 is dual to a three dimensional superconformal field theory. We use the fact that the three dimensional self-mirror duality is preserved by exact marginal operators, as observed by Strassler.
Constraints on Black Hole/Host Galaxy Co-evolution and Binary Stalling Using Pulsar Timing Arrays

Pulsar timing arrays are now setting increasingly tight limits on the gravitational wave background from binary supermassive black holes (SMBHs). But as upper limits grow more constraining, what can be implied about galaxy evolution? We investigate which astrophysical parameters have the largest impact on predictions of the strain spectrum and provide a simple framework to directly translate between measured values for the parameters of galaxy evolution and pulsar timing array (PTA) limits on the gravitational wave background of binary SMBHs. We find that the most influential observable is the relation between a host galaxy's central bulge and its central black hole, , which has the largest effect on the mean value of the characteristic strain amplitude. However, the variance of each prediction is dominated by uncertainties in galaxy stellar mass functions. Using this framework with the best published PTA limit, we can set limits on the shape and scatter of the relation. We find our limits to be in contention with strain predictions using two leading measurements of this relation. We investigate several possible reasons for this disagreement. If we take the relations to be correct within a simple power-law model for the gravitational wave background, then the inconsistency is reconcilable by allowing for an additional "stalling" time between a galaxy merger and evolution of a binary SMBH to sub-parsec scales, with lower limits on this timescale of ~1–2 Gyr.
Phase Transitions in Edge-Weighted Exponential Random Graphs: Near-Degeneracy and Universality

Conventionally used exponential random graphs cannot directly model weighted networks as the underlying probability space consists of simple graphs only. Since many substantively important networks are weighted, this limitation is especially problematic. We extend the existing exponential framework by proposing a generic common distribution for the edge weights. Minimal assumptions are placed on the distribution, that is, it is non-degenerate and supported on the unit interval. By doing so, we recognize the essential properties associated with near-degeneracy and universality in edge-weighted exponential random graphs.
Configurational mapping significantly increases the efficiency of solid-solid phase coexistence calculations via molecular dynamics: Determining the FCC-HCP coexistence line of Lennard-Jones particles.

In this study, we incorporate configuration mapping between simulation ensembles into the successive interpolation of multistate reweighting (SIMR) method in order to increase phase space overlap between neighboring simulation ensembles. This significantly increases computational efficiency over the original SIMR method in many situations. We use this approach to determine the coexistence curve of face-centered cubic–hexagonal close-packed Lennard-Jones spheres using direct molecular dynamics and SIMR. As previously noted, the coexistence curve is highly sensitive to the treatment of the van der Waals cutoff. Using a cutoff treatment, the chemical potential difference between phases is moderate and SIMR quickly finds the phase equilibrium lines with good statistical uncertainty. Using a smoothed cutoff results in nonphysical errors in the phase diagram, while the use of particle mesh Ewald for the dispersion term results in a phase equilibrium curve that is comparable with previous results. The drastically closer free energy surfaces for this case test the limits of this configuration mapping approach to phase diagram prediction.In this study, we incorporate configuration mapping between simulation ensembles into the successive interpolation of multistate reweighting (SIMR) method in order to increase phase space overlap between neighboring simulation ensembles. This significantly increases computational efficiency over the original SIMR method in many situations. We use this approach to determine the coexistence curve of face-centered cubic–hexagonal close-packed Lennard-Jones spheres using direct molecular dynamics and SIMR. As previously noted, the coexistence curve is highly sensitive to the treatment of the van der Waals cutoff. Using a cutoff treatment, the chemical potential difference between phases is moderate and SIMR quickly finds the phase equilibrium lines with good statistical uncertainty. Using a smoothed cutoff results in nonphysical errors in the phase diagram, while the use of particle mesh Ewald for the dispersion term results in a phase equilibrium curve that is comparable with previous results. The drasticall...
Simulation of a low-background proton detector for studying low-energy resonances relevant in thermonuclear reactions

A new detector is being developed at the National Superconducting Cyclotron Laboratory (NSCL) to measure low energy charged-particles from beta-delayed particle emission. These low energy particles are very important for nuclear astrophysics studies. The use of a gaseous system instead of a solid state detector decreases the sensitivity to betas while keeping high efficiency for higher mass charged particles like protons or alphas. This low sensitivity to betas minimizes their contribution to the background down to 150 keV. A detailed simulation tool based on GEANT4 has been developed for this future detector.
IDENTIFYING A SCREENING MODEL WITH MULTIDIMENSIONAL PRIVATE INFORMATION

In this paper I study the nonparametric identication of screen- ing (price discrimination) models when consumers have multidimensional pri- vate information about their taste for product characteristics. In particular, I consider the model developed by Rochet and Chon e (1998) and determine conditions to identify the cost function, the joint density of taste and the utility functions, from individual level data (on demand and prices). When the utility function is nonlinear, exogenous binary cost shifter is sucient for identication. Moreover, I show that if there are some consumer covariates and the utility is nonlinear the model is over identied. I also characterize all testable restrictions of the model on the data.
Robust Recovery via Implicit Bias of Discrepant Learning Rates for Double Over-parameterization

Recent advances have shown that implicit bias of gradient descent on over-parameterized models enables the recovery of low-rank matrices from linear measurements, even with no prior knowledge on the intrinsic rank. In contrast, for robust low-rank matrix recovery from grossly corrupted measurements, over-parameterization leads to overfitting without prior knowledge on both the intrinsic rank and sparsity of corruption. This paper shows that with a double over-parameterization for both the low-rank matrix and sparse corruption, gradient descent with discrepant learning rates provably recovers the underlying matrix even without prior knowledge on neither rank of the matrix nor sparsity of the corruption. We further extend our approach for the robust recovery of natural images by over-parameterizing images with deep convolutional networks. Experiments show that our method handles different test images and varying corruption levels with a single learning pipeline where the network width and termination conditions do not need to be adjusted on a case-by-case basis. Underlying the success is again the implicit bias with discrepant learning rates on different over-parameterized parameters, which may bear on broader applications.
Ideal aerodynamics of ground effect and formation flight

The theoretical induced-drag benefits are presented for ideally loaded wings flying in formation and ground effect. An optimum-downwash approach using a vortex-lattice implementation was used to study formations of wings loaded optimally for minimum induced drag with roll trim. An exact approach was also developed to examine the drag of elliptically loaded wings in formation. The exact approach allows for decomposition of the benefits by considering the mutual-interference contributions from different pairs of wings in a formation
Boolean Functions: Noise Stability, Non-Interactive Correlation Distillation, and Mutual Information

Let $T_{\epsilon }$ be the noise operator acting on Boolean functions $f:\{0, 1\}^{n}\to \{0, 1\}$ , where $\epsilon \in [{0, 1/2}]$ is the noise parameter. Given $\alpha >1$ and fixed mean $\mathbb {E} f$ , which Boolean function $f$ has the largest $\alpha $ -th moment $\mathbb {E}(T_\epsilon f)^\alpha $ ? This question has close connections with noise stability of Boolean functions, the problem of non-interactive correlation distillation, and Courtade-Kumar’s conjecture on the most informative Boolean function. In this paper, we characterize maximizers in some extremal settings, such as low noise ( $\epsilon =\epsilon (n)$ close to 0), high noise ( $\epsilon =\epsilon (n)$ close to 1/2), as well as when $\alpha =\alpha (n)$ is large. Analogous results are also established in more general contexts, such as Boolean functions defined on discrete torus $(\mathbb {Z}/p \mathbb {Z})^{n}$ and the problem of noise stability in a tree model.
Temporal experience modifies future thoughts: Manipulation of Libet's W influences difficulty assessment during a decision-making task

Past studies have employed the subjective experience of decision time (Libet's W) as an index of consciousness, marking the moment at which the agent first becomes aware of a decision. In the current study, we examined whether the temporal experience of W affects subsequent experience related to the action. Specifically, we tested whether W influenced the perception of difficulty in a decision-making task, hypothesizing that temporal awareness of W might influence the sense of difficulty. Consistent with our predictions, when W was perceived as early or late, participants subsequently rated the decision difficulty to be easy or difficult, respectively (Exp.1). Further investigation showed that perceived difficulty, however, did not influence W (Exp.2). Together, our findings suggest a unidirectional relationship such that W plays a role in the metacognition of difficulty evaluation. The results imply that subjective temporal experience of decision time modifies the consequential sense of difficulty.
Assessing Fiscal Risks in Bangladesh

This paper identifies, quantifies, and assesses fiscal risks in Bangladesh. By performing sensitivity analysis and using stochastic simulations, it measures risks arising from shocks to gross domes...
On the $RO(G)$-graded coefficients of dihedral equivariant cohomology

We completely calculate the $RO(G)$-graded coefficients of ordinary equivariant cohomology where $G$ is the dihedral group of order $2p$ for a prime $p>2$ both with constant and Burnside ring coefficients. The authors first proved it for $p=3$ and then the second author generalized it to arbitrary $p$. These are the first such calculations for a non-abelian group.
Identifying female phenotypes that promote behavioral isolation in a sexually dimorphic species of fish Etheostoma zonale

In sexually dimorphic species characterized by exaggerated male ornamentation, behavioral isolation is often attributed to female preferences for conspecific male signals. Yet, in a number of sexually dimorphic species, male mate choice also results in behavioral isolation. In many of these cases, the female traits that mediate species boundaries are unclear. Females in sexually dimorphic species typically lack many of the elaborate traits that are present in males and that are often used for taxonomic classification of species. In a diverse and largely sexually dimorphic group of fishes called darters (Percidae: Etheostoma), male mate choice contributes to behavioral isolation between a number of species; however, studies addressing which female traits males prefer are lacking. In this study, we identified the dominant female pattern for two sympatric species, Etheostoma zonale and Etheostoma barrenense, using pattern energy analysis, and we used discriminate function analysis to identify which aspects of female patterning can reliably classify species. We then tested the role of female features in male mate choice for E. zonale, by measuring male preference for computer animations displaying the identified (species-specific) conspecific features. We found that the region above the lateral line is important in mediating male mate preferences, with males spending a significantly greater proportion of time with animations exhibiting conspecific female patterning in this region than with animations exhibiting heterospecific female patterning. Our results suggest that the aspects of female phenotypes that are the target of male mate choice are different from the conspicuous male phenotypes that traditionally characterize species.
Disaster Knowledge and Household Preparations of Selected Communities in Central Luzon, Philippines: Basis for Enhanced Community Disaster Education Program

Disaster is nature’s worst event that can happen anytime and anywhere. It creates unfathomable destruction to everything. This study aimed to analyse and explore the disaster knowledge and household preparations of individuals in selected communities located in Central Luzon, Philippines. The study used a descriptive research design with the survey as the primary data gathering tool. One hundred thirty (130) respondents took part in the survey from two identified communities in Central Luzon using purposive sampling technique. This study also adopted and modified a research instrument which was subjected to validity and reliability test. The researcher subjected the data gathered with the following statistical tools: weighted mean, t-test, ANOVA and Pearson-r with the help of SPSS 20. The study then generated the following findings (1) the respondents were knowledgeable about disasters and the households were prepared in time of a disaster. In addition, there was a significant difference in the disaster knowledge respondents when grouped according to the community. Also, there exists a relationship between the community of the respondents and their disaster knowledge. Furthermore, a moderate and direct relationship also exists between disaster knowledge and household preparations. Based on the findings the researcher provided a suggestion for an enhanced community disaster education program.
Monte Carlo Simulation on the Stiefel Manifold via Polar Expansion

Motivated by applications to Bayesian inference for statistical models with orthogonal matrix parameters, we present polar expansion , a general approach to Monte Carlo simulation from probabilit...
A Cascade Approach to Neural Abstractive Summarization with Content Selection and Fusion.

We present an empirical study in favor of a cascade architecture to neural text summarization. Summarization practices vary widely but few other than news summarization can provide a sufficient amount of training data enough to meet the requirement of end-to-end neural abstractive systems which perform content selection and surface realization jointly to generate abstracts. Such systems also pose a challenge to summarization evaluation, as they force content selection to be evaluated along with text generation, yet evaluation of the latter remains an unsolved problem. In this paper, we present empirical results showing that the performance of a cascaded pipeline that separately identifies important content pieces and stitches them together into a coherent text is comparable to or outranks that of end-to-end systems, whereas a pipeline architecture allows for flexible content selection. We finally discuss how we can take advantage of a cascaded pipeline in neural text summarization and shed light on important directions for future research.
Expected-Time Cryptography: Generic Techniques and Applications to Concrete Soundness

This paper studies concrete security with respect to expected-time adversaries. Our first contribution is a set of generic tools to obtain tight bounds on the advantage of an adversary with expected-time guarantees. We apply these tools to derive bounds in the random-oracle and generic-group models, which we show to be tight.
Triangle-Net: Towards Robustness in Point Cloud Learning

Three dimensional (3D) object recognition is becoming a key desired capability for many computer vision systems such as autonomous vehicles, service robots and surveillance drones to operate more effectively in unstructured environments. These real-time systems require effective classification methods that are robust to various sampling resolutions, noisy measurements, and unconstrained pose configurations. Previous research has shown that points’ sparsity, rotation and positional inherent variance can lead to a significant drop in the performance of point cloud based classification techniques. However, neither of them is sufficiently robust to multifactorial variance and significant sparsity. In this regard, we propose a novel approach for 3D classification that can simultaneously achieve invariance towards rotation, positional shift, scaling, and is robust to point sparsity. To this end, we introduce a new feature that utilizes graph structure of point clouds, which can be learned end-to-end with our proposed neural network to acquire a robust latent representation of the 3D object. We show that such latent representations can significantly improve the performance of object classification and retrieval tasks when points are sparse. Further, we show that our approach outperforms PointNet and 3DmFV by 35.0% and 28.1% respectively in ModelNet 40 classification tasks using sparse point clouds of only 16 points under arbitrary SO(3) rotation.
Privacy-Preserving Policy Synthesis in Markov Decision Processes

In decision-making problems, the actions of an agent may reveal sensitive information that drives its decisions. For instance, a corporation’s investment decisions may reveal its sensitive knowledge about market dynamics. To prevent this type of information leakage, we introduce a policy synthesis algorithm that protects the privacy of the transition probabilities in a Markov decision process. We use differential privacy as the mathematical definition of privacy. The algorithm first perturbs the transition probabilities using a mechanism that provides differential privacy. Then, based on the privatized transition probabilities, we synthesize a policy using dynamic programming. Our main contribution is to bound the "cost of privacy," i.e., the difference between the expected total rewards with privacy and the expected total rewards without privacy. We also show that computing the cost of privacy has time complexity that is polynomial in the parameters of the problem. Moreover, we establish that the cost of privacy increases with the strength of differential privacy protections, and we quantify this increase. Finally, numerical experiments on two example environments validate the established relationship between the cost of privacy and the strength of data privacy protections.
Characterization of the Ammonium Bending Vibrations in Two-Dimensional Hybrid Lead-Halide Perovskites from Raman Spectroscopy and First-Principles Calculations

The facile synthesis and electronic properties of two-dimensional hybrid organic–inorganic perovskites (2D HOIPs) make these self-assembled systems an important class of energy materials. The basic...
Principal component analysis using frequency components of multivariate time series

Abstract Dimension reduction techniques for multivariate time series decompose the observed series into a few useful independent/orthogonal univariate components. A spectral domain method is developed for multivariate second-order stationary time series that linearly transforms the observed series into several groups of lower-dimensional multivariate subseries. These multivariate subseries have non-zero spectral coherence among components within a group but have zero spectral coherence among components across groups. The observed series is expressed as a sum of frequency components whose variances are proportional to the spectral matrices at the respective frequencies. The demixing matrix is then estimated using an eigendecomposition on the sum of the variance matrices of these frequency components and its asymptotic properties are derived. Finally, a consistent test on the cross-spectrum of pairs of components is used to find the desired segmentation into the lower-dimensional subseries. The numerical performance of the proposed method is illustrated through simulation examples and an application to modeling and forecasting wind data is presented.
Unsupervised Attention Based Instance Discriminative Learning for Person Re-Identification

Recent advances in person re-identification have demonstrated enhanced discriminability, especially with supervised learning or transfer learning. However, since the data requirements—including the degree of data curations—are becoming increasingly complex and laborious, there is a critical need for unsupervised methods that are robust to large intra-class variations, such as changes in perspective, illumination, articulated motion, resolution, etc. Therefore, we propose an unsupervised framework for person re-identification which is trained in an end-to-end manner without any pre-training. Our proposed framework leverages a new attention mechanism that combines group convolutions to (1) enhance spatial attention at multiple scales and (2) reduce the number of trainable parameters by 59.6%. Additionally, our framework jointly optimizes the network with agglomerative clustering and instance learning to tackle hard samples. We perform extensive analysis using the Market1501 and DukeMTMC-reID datasets to demonstrate that our method consistently outperforms the state-of-the-art methods (with and without pre-trained weights).
An Iterative Cyclic Algorithm for Designing Vaccine Distribution Networks in Low and Middle-Income Countries

The World Health Organization – Expanded Programme on Immunization (WHO-EPI) was developed to ensure that all children have access to common childhood vaccinations. Unfortunately, because of inefficient distribution networks and cost constraints, millions of children in many low and middle-income countries still go without being vaccinated. In this paper, we formulate a mathematical programming model for the design of a typical WHO-EPI network with the goal of minimizing costs while providing the opportunity for universal coverage. Since it is only possible to solve small versions of the model optimally, we describe an iterative heuristic that cycles between solving restrictions of the original problem and show that it can find very good solutions in reasonable time for larger problems that are not directly solvable.
A comprehensive spatial-temporal infection model

Abstract Motivated by analogies between the spread of infections and of chemical processes, we develop a model that accounts for infection and transport where infected populations correspond to chemical species. Areal densities emerge as the key variables, thus capturing the effect of spatial density. We derive expressions for the kinetics of the infection rates, and for the important parameter R 0 , that include areal density and its spatial distribution. We present results for a batch reactor, the chemical process equivalent of the SIR model, where we examine how the dependence of R 0 on process extent, the initial density of infected individuals, and fluctuations in population densities effect the progression of the disease. We then consider spatially distributed systems. Diffusion generates traveling waves that propagate at a constant speed, proportional to the square root of the diffusivity and R 0 . Preliminary analysis shows a similar behavior for the effect of stochastic advection.
Trimmed Constrained Mixed Effects Models: Formulations and Algorithms

Mixed effects (ME) models inform a vast array of problems in the physical and social sciences, and are pervasive in meta-analysis. We consider ME models where the random effects component is linear...
A Better Death in Britain

In the United States, terminally ill patients and their physicians often avoid discussing the inevitability of death and planning for it. As a result, these patients miss opportunities to make choices that comport with their values and preferences. In the absence of such decisions, the default model is to "err on the side of life," which often results in overtreatment, inappropriate prolongation of life, and avoidable suffering. This Article discusses trends in end-of-life care in the the United States and compares these trends with the the U.K.'s Liverpool Care Pathway and its approach to end-of-life care. Although the Liverpool Care Pathway generated clearly superior outcomes compared with the United States' model in all dimensions - care availability, quality, and cost - it nevertheless generated controversy. Poor physician-patient communication represents the shared barrier to high quality end-of-life care in both countries. Although the United States' medical community and other interested groups have begun serious work into methods to improve the quality of communication and care at the end of life, they are a long way from understanding how best to bridge the gap between theory and practice across a vast and diffuse health care system.
Protecting Tenants at Foreclosure By Funding Needed Repairs

Among the victims of the current mortgage foreclosure crisis, tenants of buildings in foreclosure are often innocent, harmed, and overlooked. When a landlord defaults on the mortgage, tenants often suffer from neglected repairs, lack of heat and hot water, and other code violations. A recent case from New York Supreme Court for Bronx County shows how tenants can use equitable arguments to force a lender to advance funds to a receiver in order to cover the cost of repairs, even before the lender obtains a judgment of foreclosure. This note argues that foreclosure courts should entertain tenants' equitable arguments and grant relief where appropriate, as well as for statutory reform to make relief more straightforward.
Shareholder Compensation as Dividend

This Article questions the prevailing view that securities fraud actions suffer from a circularity problem. Because shareholder plaintiffs are owners of the defendant corporation, it is commonly argued that shareholder compensation is a payment from shareholders to themselves with substantial transaction costs in the form of attorney fees. But shareholder compensation is no more circular than a dividend, which is a cash payment to shareholders from the company they own with substantial transaction costs in the form of taxes. In fact, shareholder compensation is less circular than a dividend because it is a transfer to shareholders who purchased stock when the price was inflated by fraud from those who did not. Shareholder compensation serves an important loss spreading function that is facilitated by the insurance market. Shareholder compensation may also capture some of the benefits of paying dividends, such as signaling and reducing agency costs, though it may do so more effectively if companies could resolve securities fraud actions by paying a preemptive dividend.
TEACHER QUALITY AND TEACHER MOBILITY

There is growing concern among policy makers over the quality of the teacher workforce in general, and the distribution of effective teachers across schools. The impact of teacher attrition on overall teacher quality will depend on the effectiveness of teachers who leave the profession. Likewise, teacher turnover may alleviate or worsen inequities in the distribution of teachers, depending on which teachers change schools or leave teaching and who replaces them. Using matched student–teacher panel data from the state of Florida, we examine teacher mobility across the distribution of effectiveness (as measured by teacher value added). We find that top-quartile and bottom-quartile teachers exit at a higher rate than do average-quality teachers. Additionally, as the share of peer teachers with more experience, advanced degrees, or professional certification increases, the likelihood of moving within-district decreases. We also find some evidence of assortative matching among teachers—more productive reading/...
Cultural cognition of scientific consensus

Why do members of the public disagree – sharply and persistently – about facts on which expert scientists largely agree? We designed a study to test a distinctive explanation: the cultural cognition of scientific consensus. The ‘cultural cognition of risk’ refers to the tendency of individuals to form risk perceptions that are congenial to their values. The study presents both correlational and experimental evidence confirming that cultural cognition shapes individuals’ beliefs about the existence of scientific consensus, and the process by which they form such beliefs, relating to climate change, the disposal of nuclear wastes, and the effect of permitting concealed possession of handguns. The implications of this dynamic for science communication and public policy‐making are discussed.
The Impact of the Rise and Fall of Chevron on the Executive's Power to Make and Interpret Law

The Supreme Court’s willingness to defer to agency interpretations of ambiguous statutes has vacillated over the past seventy years. The Court’s vacillation has dramatically impacted the executive’s power to make and interpret law. This Article examines how the Court augmented then constricted executive lawmaking power and ceded then reclaimed executive interpretive power with a single case and its legal progeny. Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc.1 and its aftermath dramatically altered the executive’s power to make and interpret law. Prior to Chevron, Congress had the primary responsibility for lawmaking, while agencies made policy choices primarily when Congress explicitly delegated that power to them. Also, prior to Chevron, the judiciary resolved questions of statutory interpretation of regulatory statutes with a bifurcated approach: agencies did not receive deference when they resolved issues involving pure questions of law, but did receive some level of deference when they resolved issues involving questions of law application. In short, prior to Chevron, the executive was an expert advisor, not a law-maker or law interpreter. With its holding in Chevron, the Court dramatically, and likely
On the Speed of Transition in Central and Eastern Europe : Does On-the-Job Search Matter?

This paper examines how the on-the-job search of workers in the state sector who are seeking jobs in the private sector affects private sector employment, the unemployment level, and the unemployment duration in the transition economies of Central and Eastern Europe. The main finding is that on-the-job searching can account for the coexistence of a quickly growing private sector and a high unemployment level of long duration. The paper also addresses the issue of the optimal (output maximizing) rate of state sector closure and finds that the rate is slower when workers are simultaneously job hunting than when they are not.
The extent of price misalignment in prediction markets

We study misaligned prices for logically related contracts in prediction markets. First, we uncover persistent arbitrage opportunities for risk-neutral investors between identical contracts on different exchanges. Examining the impact of several thousand dollars of transactions on the exchanges themselves in a randomized field trial, we document that price support extends well beyond what is seen in the published order book and that arbitrage opportunities are significantly larger than purely observational measurements indicate. Second, we demonstrate misalignment among identical and logically related contracts listed on the same exchange that cluster around moments of high information flow, when related contracts systemically shut down or fail to respond efficiently. Third, we document bounded rationality in prediction markets; examples include: consistent asymmetry between buying and selling, leaving the average return for selling higher than for buying; and persistent price lags between exchanges. Despite these signs of departure from theoretical optimality, the markets studied function well on balance, considering the sometimes complex and subtle relationships among contracts. Yet, we detail how to improve prediction markets by moving the burden of finding and fixing logical contradictions into the exchange and providing flexible trading interfaces, both of which free traders to focus on providing meaningful information in the form they find most natural.
Trade Policy Determinants and Trade Reform in a Developing Country: The Case of Colombia

In this paper, I empirically examine trade policy determinants and trade reform in a developing country setting by using a political economy of trade policy model to guide my estimations for Colombia between 1983 and 1998. I introduce a novel approach to estimating the extra political weights placed by the government on the well-being of producers relative to average citizens. This is under the assumption that producers are organized in terms of trade policy while the public is not. I measure
Switched at the fertility clinic: determining maternal rights when a child is born from stolen or misdelivered genetic material.

Modern reproductive technology has been a blessing for many couples unable to conceive naturally. Through procedures such as in vitro fertilization, physicians are able to harvest eggs from the mother, fertilize them outside the womb, and freeze them for later implantation. A scandal at a California fertility clinic, however, illustrated the dangers of this process--namely, the possibility that an egg or embryo produced by one woman might be improperly implanted in the uterus of another, resulting in a legal battle to determine parental rights over the child. This article reviews the legal community's response to issues raised by reproductive technology in general and suggests how the law might be adapted to the special case of stolen or misdelivered genetic material. The article finds that traditional parentage laws yield no easy answers because they were crafted in simpler times and cling to the theory that a child can have only one legal mother. The article suggests that a more progressive solution is needed when genetic material is shared without the mother's consent. The article proposes that if both mothers demonstrate an intent to parent the child, the courts should treat them both as legal parents and resolve their competing claims as a custody issue using a modified best interests analysis.
Taxing transactions in futures markets: Objectives and effects

In the last few years various legislative proposals have been made to impose a transaction or excise tax on securities and derivative market transactions. Although there have been considerable discussion and analysis of the wisdom of imposing such a tax on securities markets, there has been no analysis of the pros and cons of extending the tax to futures markets. This article attempts to fill this gap, first, by examining the various rationales advanced to support a tax on securities markets to determine their applicability to futures markets and, second, by analyzing the likely effects of the tax on the competitiveness and efficiency of futures markets. In addition, the revenue-raising potential of a tax on futures transactions is evaluated. I conclude that a tax on futures markets will not achieve any important social objective and will not generate much revenue.
The Strategic Formation of Networks: Experimental Evidence

We use a laboratory experiment to explore dynamic network formation in a six-player game where link creation requires mutual consent. The analysis of network outcomes suggests that the process tends to converge to the pairwise-stable (PWS) equilibrium when it exists and not to converge at all when it does not. When multiple PWS equilibria exist, subjects tend to coordinate on the high-payoff one. The analysis at the single choice level indicates that the percentage of myopically rational behavior is generally high. Deviations are more prevalent when actions are reversible, when marginal payoff losses are smaller and when deviations involve excessive links that can be removed unilaterally later on. There is, however, some heterogeneity across subjects.
Optionality in Merger Agreements

The credit crisis of 2008 and the subsequent collapse of a number of high-profile acquisition transactions put a spotlight on contracting practices that embedded optionality into merger agreements by way of the reverse termination fee and its attendant triggers. This article examines whether reverse termination fees are a symmetrical response to the seller's judiciallymandated fiduciary termination right and whether such fees represent an efficient transactional term. A series of Delaware cases over the last decade limited the degree to which buyers could rely on deal protection measures in merger agreements to prevent a seller from accepting a superior second bid resulting in a judicially-created fiduciary put. Where courts require seller termination rights, it is possible that buyers might attempt to negotiate symmetrical "optionality" for buyers elsewhere in the merger agreement. This article investigates whether the termination triggers that accompany reverse termination fees are that symmetrical response. Using a sample of 644 acquisitions from 2003 through 2008, which includes 105 transactions where strategic buyers negotiated a reverse termination fee, this article provides an empirical account of the use of reverse termination fees by strategic buyers, including the first taxonomy of reverse termination fee triggers. This article concludes first that reverse termination fee triggers are not a symmetrical response to the judicially mandated seller's fiduciary termination rights. Second, to the extent reverse termination rights mimic termination rights in size, they may be inefficient terms. The results of this study provide some guidance to courts as they are asked to assess the viability of reverse termination fees and the degree of optionality embedded in the modern merger agreement. Assistant Professor of Law, Boston College Law School. The author is grateful for the support of the Boston College Law School Summer Research Fund and for the participation of faculty in presentations at Boston College Law School and Washington & Lee Law School. Thanks also to Chuck Whitehead, Afra Afsharipour, Steven Davidoff, and Elizabeth Nowicki for comments on earlier drafts and to Aaron Fine (BCLS, '10) for research assistance. 790 DELAWARE JOURNAL OF CORPORATE LAW [Vol. 35 TABLE OF CONTENTS Page
Mask Formulas for Cograssmannian Kazhdan-Lusztig Polynomials

We give two constructions of sets of masks on cograssmannian permutations that can be used in Deodhar’s formula for Kazhdan–Lusztig basis elements of the Iwahori–Hecke algebra. The constructions are respectively based on a formula of Lascoux–Schutzenberger and its geometric interpretation by Zelevinsky. The first construction relies on a basis of the Hecke algebra constructed from principal lower order ideals in Bruhat order and a translation of this basis into sets of masks. The second construction relies on an interpretation of masks as cells of the Bott–Samelson resolution. These constructions give distinct answers to a question of Deodhar.
The Superior Measure of PSID Consumption: an Update

Abstract This paper provides an update to Skinner's (1987) predicted consumption measure for households in the Panel Study of Income Dynamics from 1980 to 2003. More than 80% of the variance in total non-durable consumption is explained by three expenditure components.
“I only want trust”: norms, trust, and autonomy

Abstract Examines the way norms are created and treated in family law. Divorce results when one of the spouses feels that the other has violated trust norms internal to the couple. At the same time, the award of custody speaks to an external norm of societal trust of parenting. When one spouse becomes a noncustodial parent, he or she loses the autonomy and other social supports given to a custodial parent or parents. Empirically, the paper shows the relationship between violation of internal trust norms and divorce, and between the loss of custodial status and depression. The paper also tests whether the common practice of awarding joint legal custody assuages the situation, and concludes that it does not.
The role of foreign institutional investors in restraining earnings management activities across countries

This study investigates the role of foreign institutional investors (FIIs) in restraining earnings management activities of firms under varying levels of investor protection. Firms manage their earnings less when independent FIIs are among their shareholders, especially for firms in which monitoring is more valuable – firms in weak investor protection countries and when firms have greater growth opportunities. These effects are robust to a quasi-exogenous shock to FIIs’ shareholdings, unobserved firm heterogeneity, and alternative earning management measures. FIIs are associated with an increase in foreign director presence on corporate boards and audit committees.
Household leveraging and deleveraging

Abstract U.S. households' debt skyrocketed between 2000 and 2007, and has been falling since. This leveraging (and deleveraging) cycle cannot be accounted for by the relaxation, and subsequent tightening, of collateral requirements in mortgage markets observed during the same period. We base this conclusion on a quantitative dynamic general equilibrium model calibrated using macroeconomic aggregates and microeconomic data from the Survey of Consumer Finances. From the perspective of the model, the credit cycle is more likely due to factors that impacted house prices more directly, thus affecting the availability of credit through a change in collateral values. In either case, the macroeconomic consequences of leveraging and deleveraging are relatively minor, because the responses of borrowers and lenders roughly wash out in the aggregate. These results suggest that household debt overhang alone cannot account for the slow recovery from the Great Recession.
HEAVY-ELEMENT DISPERSION IN THE METAL-POOR GLOBULAR CLUSTER M92*

Dispersion among the light elements is common in globular clusters (GCs), while dispersion among heavier elements is less common. We present detection of r-process dispersion relative to Fe in 19 red giants of the metal-poor GC M92. Using spectra obtained with the Hydra multi-object spectrograph on the WIYN Telescope at Kitt Peak National Observatory, we derive differential abundances for 21 species of 19 elements. The Fe-group elements, plus Y and Zr, are homogeneous at a level of 0.07-0.16 dex. The heavy-elements La, Eu, and Ho exhibit clear star-to-star dispersion spanning 0.5-0.8 dex. The abundances of these elements are correlated with one another, and we demonstrate that they were produced by r-process nucleosynthesis. This r-process dispersion is not correlated with the dispersion in C, N, or Na in M92, indicating that r-process inhomogeneities were present in the gas throughout star formation. The r-process dispersion is similar to that previously observed in the metal-poor GC M15, but its origin in M15 or M92 is unknown at present.
Decimal Pricing and Information‐Based Trading: Tick Size and Informational Efficiency of Asset Price

: In this study we analyze the effect of tick size on information-based trading. Although prior studies provide extensive evidence on the effect of tick size on market quality measures such as spreads, depths, and return volatility, there is little evidence as to the effect of tick size on the informational efficiency of asset price. Our results indicate that the probability of information-based trading during the post-decimal period is significantly greater than the corresponding figure during the pre-decimal period. We also show that the increase in information-based trading after decimalization cannot be attributed to concurrent changes in stock attributes. We interpret our findings as evidence that the smaller tick size under penny pricing encourages information-based trading and thereby raises the informational efficiency of asset price.
Dividend Policy inside the Multinational Firm

Three factors significantly influence profit repatriations by U.S. multinational firms: tax considerations, domestic financing and investment needs, and agency problems inside firms. Dividend repatriations are surprisingly persistent and resemble dividend payments to external shareholders. Tax considerations are influential but not decisive. Affiliates whose organizational forms carry differing tax treatments nonetheless feature similar repatriation polices, and certain firms incur avoidable tax penalties by simultaneously repatriating profits and investing new equity. Parental financing needs also matter, as parents with larger dividend payouts to external shareholders, and highly levered parent companies with profitable domestic investment opportunities, draw on the resources of their foreign affiliates. Finally, affiliates that are incompletely controlled are more likely than others to make regularized dividend payments and to trigger avoidable tax costs through repatriations. Taken together, the results indicate that traditional corporate finance concerns – taxation, costly external finance, and agency problems – are also critical to the internal capital markets of multinational firms. JEL Classifications: F23, G31, G35, H25, H87. Mihir A. Desai C. Fritz Foley James R. Hines Jr. Harvard Business School Harvard Business School Department of Economics Baker 265 Baker 265 University of Michigan Soldiers Field Soldiers Field 611 Tappan Street Boston, MA 02163 Boston, MA 02163 Ann Arbor, MI 48109-1220 mdesai@hbs.edu ffoley@hbs.edu jrhines@umich.edu