cssi/SciSciGPT-SciSciNet huggingface dataset:
A 40 Myr OLD GASEOUS CIRCUMSTELLAR DISK AT 49 CETI: MASSIVE CO-RICH COMET CLOUDS AT YOUNG A-TYPE STARS

The gaseous molecular disk that orbits the main-sequence A-type star 49 Ceti has been known since 1995, but the stellar age and the origin of the observed carbon monoxide molecules have been unknown. We now identify 49 Ceti as a member of the 40 Myr old Argus Association and present a colliding comet model to explain the high CO concentrations seen at 49 Ceti and the 30 Myr old A-type star HD 21997. The model suggests that massive-400 Earth mass-analogs of the Sun's Kuiper Belt are in orbit around some A-type stars, that these large masses are composed primarily of comet-like objects, and that these objects are rich in CO and perhaps also CO{sub 2}. We identify additional early-type members of the Argus Association and the Tucana/Horologium and Columba Associations; some of these stars display excess mid-infrared emission as measured with the Widefield Infrared Survey Explorer.
Relationship between Intensity of White-Light Flares and Proton Flux of Solar Energetic Particles

Solar energetic particles (SEPs), including protons and heavy ions, are believed to be accelerated either by CME shock or by magnetic reconnection. The latter also produces solar flares, in which the white light flares (WLFs) are among the most energetic ones. Magnetic reconnections occur in the corona and the accelerated particles propagate both downward and upward along the magnetic loops. The former is the source of flare emission and the latter is thought to be SEPs. Therefore, a comparison between flare emission and SEP events provides valuable constraint in determining the acceleration site of SEPs. We collect 43 SEP events, observed from 2010 to 2017, and investigate their correlation with WL emission and SXR flus, observed by SDO/HMI and GOES, respectively. Our preliminary results show: 1) Among 47 SEP events, 39 of which do not have detectable flare emissions in white light and SXR. 2) Most strong WLFs are not associated with SEPs. 3) No clear correlation is found between the proton flux and the equivalent area, a quantity that measures the magnitude of WLF emission. A straightforward speculation is that the acceleration process could be different for SEPs and the energetic electrons powering WLFs in the events analyzed.
Weakly Asymmetric Non-Simple Exclusion Process and the Kardar–Parisi–Zhang Equation

We analyze a class of non-simple exclusion processes and the corresponding growth models by generalizing the discrete Cole–Hopf transformation of Gartner (Stoch Process Appl, 27:233–260, 1987). We identify the main non-linearity and eliminate it by imposing a gradient type condition. For hopping range at most 3, using the generalized transformation, we prove the convergence of the exclusion process toward the Kardar–Parisi–Zhang (kpz) equation. This is the first universality result under the weak asymmetry concerning interacting particle systems. While this class of exclusion processes are not explicitly solvable, under the weak asymmetry we obtain the exact one-point limiting distribution for the step initial condition by using the previous result of Amir et al. (Commun Pure Appl Math, 64(4): 466–537, 2011) and our convergence result.
The Abacus Cosmos: A Suite of Cosmological N-body Simulations

National Science Foundation [AST-1313285, 1228509, AST-1312699]; U.S. Department of Energy [DE-SC0013718]
Simulated multiple reference training improves low-resource machine translation

Many valid translations exist for a given sentence, yet machine translation (MT) is trained with a single reference translation, exacerbating data sparsity in low-resource settings. We introduce Simulated Multiple Reference Training (SMRT), a novel MT training method that approximates the full space of possible translations by sampling a paraphrase of the reference sentence from a paraphraser and training the MT model to predict the paraphraser’s distribution over possible tokens. We demonstrate the effectiveness of SMRT in low-resource settings when translating to English, with improvements of 1.2 to 7.0 BLEU. We also find SMRT is complementary to back-translation.
Presolar Diamond in Meteorites

Presolar diamond, the carrier of the isotopically anomalous Xe component Xe–HL, was the first mineral type of presolar dust that was isolated from meteorites. The excesses in the light, p-process only isotopes 124Xe and 126Xe, and in the heavy, r-process only isotopes 134Xe and 136Xe relative to the solar ratios indicate that Xe–HL was produced in supernovae: they are the only stellar source where these two processes are believed to take place. Although these processes occur in supernovae, their physical conditions and timeframes are completely different. Yet the excesses are always correlated in diamond separates from meteorites. Furthermore, the p-process 124Xe/126Xe inferred from Xe–L and the r-process 134Xe/136Xe from Xe–H do not agree with the p-process and r-process ratios derived from the solar system abundance, and the inferred p-process ratio does not agree with those predicted from stellar models. The ‘rapid separation scenario’, where the separation of Xe and its radiogenic precursors Te and I takes place at the very early stage (7900 s after the end of the r-process), has been proposed to explain Xe–H. Alternatively, mixing of 20% of material that experienced neutron burst and 80% of solar material can reproduce the pattern of Xe–H, although Xe–L is not accounted for with this scenario.
Central extensions of smooth 2–groups and a finite-dimensional string 2–group

We provide a model of the String group as a central extension of finite-dimensional 2‐groups in the bicategory of Lie groupoids, left-principal bibundles, and bibundle maps. This bicategory is a geometric incarnation of the bicategory of smooth stacks and generalizes the more naive 2‐category of Lie groupoids, smooth functors and smooth natural transformations. In particular this notion of smooth 2‐group subsumes the notion of Lie 2‐group introduced by Baez and Lauda [5]. More precisely we classify a large family of these central extensions in terms of the topological group cohomology introduced by Segal [56], and our String 2‐group is a special case of such extensions. There is a nerve construction which can be applied to these 2‐groups to obtain a simplicial manifold, allowing comparison with the model of Henriques [23]. The geometric realization is an A1 ‐space, and in the case of our model, has the correct homotopy type of String.n/. Unlike all previous models [58; 60; 33; 23; 7] our construction takes place entirely within the framework of finitedimensional manifolds and Lie groupoids. Moreover within this context our model is characterized by a strong uniqueness result. It is a canonical central extension of Spin.n/. 57T10, 22A22, 53C08; 18D10 The String group is a group (or A1 ‐space) which is a 3‐connected cover of Spin.n/. It has connections to string theory, the generalized cohomology theory topological modular forms (tmf ), and to the geometry and topology of loop space. Many of these relationships can be explored homotopy theoretically, but a geometric model of the String group would help provide a better understanding of these subjects and their interconnections. Over the past decade there have been several attempts to provide geometric models of the String group; see Stolz [58], Stolz and Teichner [60], Jurco [33], Henriques [23] and Baez, Stevenson, Crans and Schreiber [7]. The most recent of these use the language of higher categories, and consequently string differential geometry also provides a test case for the emerging field of higher categorical differential geometry; see Waldorf [64] and Sati, Schreiber and Stasheff [51; 52].
Big Data strategies for Data Center Infrastructure management using a 3D gaming platform

High Performance Computing (HPC) is intrinsically linked to effective Data Center Infrastructure Management (DCIM). Cloud services and HPC have become key components in Department of Defense and corporate Information Technology competitive strategies in the global and commercial spaces. As a result, the reliance on consistent, reliable Data Center space is more critical than ever. The costs and complexity of providing quality DCIM are constantly being tested and evaluated by the United States Government and companies such as Google, Microsoft and Facebook. This paper will demonstrate a system where Big Data strategies and 3D gaming technology is leveraged to successfully monitor and analyze multiple HPC systems and a lights-out modular HP EcoPOD 240a Data Center on a singular platform. Big Data technology and a 3D gaming platform enables the relative real time monitoring of 5000 environmental sensors, more than 3500 IT data points and display visual analytics of the overall operating condition of the Data Center from a command center over 100 miles away. In addition, the Big Data model allows for in depth analysis of historical trends and conditions to optimize operations achieving even greater efficiencies and reliability.
Inflation with general initial conditions for scalar perturbations

We explore the possibility of a single field quasi-de Sitter inflationary model with general initial state for primordial fluctuations. In this paper, first we compute the power spectrum and the bispectrum of scalar perturbations with coherent state as the initial state. We find that a large class of coherent states are indistinguishable from the Bunch-Davies vacuum state and hence consistent with the current observations. In case of a more general initial state built over Bunch-Davies vacuum state, we show that the constraints on the initial state from observed power spectrum and local bispectrum are relatively weak and for quasi-de Sitter inflation a large number of initial states are consistent with the current observations. However, renormalizability of the energy-momentum tensor of the fluctuations constraints the initial state further.
Impact of Semiconductor Band Tails and Band Filling on Photovoltaic Efficiency Limits

The theoretical maximum efficiency of a solar cell is typically characterized by a detailed balance of optical absorption and emission for a semiconductor in the limit of unity radiative efficiency and an ideal step-function response for the density of states and absorbance at the semiconductor band edges, known as the Shockley-Queisser limit. However, real materials have non-abrupt band edges, which are typically characterized by an exponential distribution of states, known as an Urbach tail. We develop here a modified detailed balance limit of solar cells with imperfect band edges, using optoelectronic reciprocity relations. We find that for semiconductors whose band edges are broader than the thermal energy, kT, there is an effective renormalized bandgap given by the quasi-Fermi level splitting within the solar cell. This renormalized bandgap creates a Stokes shift between the onset of the absorption and photoluminescence emission energies, which significantly reduces the maximum achievable efficiency. The abruptness of the band edge density of states therefore has important implications for the maximum achievable photovoltaic efficiency.
A case of metastatic adenocarcinoma of unknown primary in a pediatric patient: Opportunities for precision medicine.

Cancer of unknown primary (CUP) is a common diagnosis in adult oncology, but is extremely rare in pediatrics, with few published reports and none in the era of molecular profiling. Here, we describe a 13-year old boy with metastatic adenocarcinoma of unknown primary that was refractory to conventional chemotherapy. Molecular profiling revealed an activating ERBB2 D769Y variant. He subsequently achieved disease control on a lapatinib-containing regimen, and upon progression, he transiently responded to neratinib prior to dying from disease. Our case reports a rare example of pediatric CUP and highlights the utility of molecular profiling in these cases.
Band Representations and Topological Quantum Chemistry

In this article, we provide a pedagogical review of the theory of topological quantum chemistry and topological crystalline insulators. We begin with an overview of the properties of crystal symmet...
SynergicLearning: neural network-based feature extraction for highly-accurate hyperdimensional learning

Machine learning models differ in terms of accuracy, computational/memory complexity, training time, and adaptability among other characteristics. For example, neural networks (NNs) are well-known for their high accuracy due to the quality of their automatic feature extraction while brain-inspired hyperdimensional (HD) learning models are famous for their quick training, computational efficiency, and adaptability. This work presents a hybrid, synergic machine learning model that excels at all the said characteristics and is suitable for incremental, on-line learning on a chip. The proposed model comprises an NN and a classifier. The NN acts as a feature extractor and is specifically trained to work well with the classifier that employs the HD computing framework. This work also presents a parameterized hardware implementation of the said feature extraction and classification components while introducing a compiler that maps any arbitrary NN and/or classifier to the aforementioned hardware. The proposed hybrid machine learning model has the same level of accuracy (i.e. ±1%) as NNs while achieving at least 10% improvement in accuracy compared to HD learning models. Additionally, the end-to-end hardware realization of the hybrid model improves power efficiency by 1.60x compared to state-of-the-art, high-performance HD learning implementations while improving latency by 2.13x. These results have profound implications for the application of such synergic models in challenging cognitive tasks.
Safe and Private Forward-trading Platform for Transactive Microgrids

Power grids are evolving at an unprecedented pace due to the rapid growth of distributed energy resources (DER) in communities. These resources are very different from traditional power sources, as they are located closer to loads and thus can significantly reduce transmission losses and carbon emissions. However, their intermittent and variable nature often results in spikes in the overall demand on distribution system operators (DSO). To manage these challenges, there has been a surge of interest in building decentralized control schemes, where a pool of DERs combined with energy storage devices can exchange energy locally to smooth fluctuations in net demand. Building a decentralized market for transactive microgrids is challenging, because even though a decentralized system provides resilience, it also must satisfy requirements such as privacy, efficiency, safety, and security, which are often in conflict with each other. As such, existing implementations of decentralized markets often focus on resilience and safety but compromise on privacy. In this article, we describe our platform, called TRANSAX, which enables participants to trade in an energy futures market, which improves efficiency by finding feasible matches for energy trades, enabling DSOs to plan their energy needs better. TRANSAX provides privacy to participants by anonymizing their trading activity using a distributed mixing service, while also enforcing constraints that limit trading activity based on safety requirements, such as keeping planned energy flow below line capacity. We show that TRANSAX can satisfy the seemingly conflicting requirements of efficiency, safety, and privacy. We also provide an analysis of how much trading efficiency is lost. Trading efficiency is improved through the problem formulation, which accounts for temporal flexibility, and system efficiency is improved using a hybrid-solver architecture. Finally, we describe a testbed to run experiments and demonstrate its performance using simulation results.
Learning properties of ordered and disordered materials from multi-fidelity data

Predicting the properties of a material from the arrangement of its atoms is a fundamental goal in materials science. While machine learning has emerged in recent years as a new paradigm to provide rapid predictions of materials properties, their practical utility is limited by the scarcity of high-fidelity data. Here, we develop multi-fidelity graph networks as a universal approach to achieve accurate predictions of materials properties with small data sizes. As a proof of concept, we show that the inclusion of low-fidelity Perdew–Burke–Ernzerhof band gaps greatly enhances the resolution of latent structural features in materials graphs, leading to a 22–45% decrease in the mean absolute errors of experimental band gap predictions. We further demonstrate that learned elemental embeddings in materials graph networks provide a natural approach to model disorder in materials, addressing a fundamental gap in the computational prediction of materials properties. Multi-fidelity graph networks learn more effective representations for materials from large data sets of low-fidelity properties, which can then be used to make accurate predictions of high-fidelity properties, such as the band gaps of ordered and disordered crystals and energies of molecules.
Nonintrusive manufactured solutions for ablation

The study of heat transfer and ablation plays an important role in many problems of scientific and engineering interest. As with the computational simulation of any physical phenomenon, the first step toward establishing credibility in ablation simulations involves code verification. Code verification is typically performed using exact and manufactured solutions. However, manufactured solutions generally require the invasive introduction of an artificial forcing term within the source code such that the code solves a modified problem for which the solution is known. In this paper, we present a nonintrusive method for manufacturing solutions for a non-decomposing ablation code, which does not require the addition of a source term.
Improved analysis of CRISPR fitness screens and reduced off-target effects with the BAGEL2 gene essentiality classifier

Identifying essential genes in genome-wide loss-of-function screens is a critical step in functional genomics and cancer target finding. We previously described the Bayesian Analysis of Gene Essentiality (BAGEL) algorithm for accurate classification of gene essentiality from short hairpin RNA and CRISPR/Cas9 genome-wide genetic screens. We introduce an updated version, BAGEL2, which employs an improved model that offers a greater dynamic range of Bayes Factors, enabling detection of tumor suppressor genes; a multi-target correction that reduces false positives from off-target CRISPR guide RNA; and the implementation of a cross-validation strategy that improves performance ~ 10× over the prior bootstrap resampling approach. We also describe a metric for screen quality at the replicate level and demonstrate how different algorithms handle lower quality data in substantially different ways. BAGEL2 substantially improves the sensitivity, specificity, and performance over BAGEL and establishes the new state of the art in the analysis of CRISPR knockout fitness screens. BAGEL2 is written in Python 3 and source code, along with all supporting files, are available on github ( https://github.com/hart-lab/bagel ).
Getting on board: The monitoring effect of institutional directors

Abstract We identify a sample of firms with directors employed by institutional investors and examine the effect of a direct channel of institutional monitoring. Using difference-in-differences tests, we find weak evidence that institutional directors have a positive effect on informational efficiency. More importantly, institutional directors have a significantly positive impact on stock returns over the long run. Further analysis shows that the presence of institutional directors leads to a slight increase of managerial entrenchment. Consistent with the notion that entrenched managers reduce risk-taking, we also find significant decreases in R&D investments and financial leverage, and significant increases in payouts for firms with institutional directors. The findings suggest that aligning with the interest of long-term investors, institutional directors deter firms from pursuing potentially value-decreasing investment projects and influence firms to return value to investors through lower debts and higher payouts, mainly share repurchases.
Adaptive Robust Quadratic Programs using Control Lyapunov and Barrier Functions

This paper presents adaptive robust quadratic program (QP) based control using control Lyapunov and barrier functions for nonlinear systems subject to time-varying and state-dependent uncertainties. An adaptive estimation law is proposed to estimate the pointwise value of the uncertainties with pre-computable estimation error bounds. The estimated uncertainty and the error bounds are then used to formulate a robust QP, which ensures that the actual uncertain system will not violate the safety constraints defined by the control barrier function. Additionally, the accuracy of the uncertainty estimation can be systematically improved by reducing the estimation sampling time, leading subsequently to reduced conservatism of the formulated robust QP. The proposed approach is validated in simulations on an adaptive cruise control problem and through comparisons with existing approaches.
North Carolina, Juvenile Court Jurisdiction, and the Resistance to Reform

North Carolina is the only state in the United States that treats all sixteenand seventeen-year-olds as adults when they are charged with criminal offenses and then denies them the ability to appeal for return to the juvenile system. Thirty-seven states cap juvenile court jurisdiction at age eighteen, while ten do so at seventeen. In addition, as reflected by international treaties and instruments, many nations of the world consider eighteen to be the most appropriate age for delineating between juvenile and adult court jurisdiction. Not surprisingly, the consequences of North Carolina’s scheme for prosecuting minors can be particularly severe. The approximately 26,000 sixteenand seventeen-yearolds who are convicted each year in North Carolina’s criminal court system encounter significant barriers when attempting to secure employment or access higher education. According to empirical research, a less punitive approach to youth crime lowers recidivism rates and better protects public safety. Further, providing intensive probationary supervision and rehabilitation to young offenders, rather than incarcerating them with adults, is consistent with recent findings in the areas of brain development
The Effects of Specialization in Audit Workpaper Review on Review Efficiency and Reviewers' Confidence

Accounting firms are currently re‐engineering their audit processes with the aim of delivering a quality audit more efficiently. One area of potential efficiency gains is the sequential and hierarchical workpaper review process. This study examines the potential for specialization to improve review efficiency and reviewer confidence. Auditing literature advises focusing each review level on specific kinds of errors (i.e., seniors on mechanical errors and managers on conceptual errors), rather than having seniors and managers perform successive all‐encompassing reviews. We find that seniors but not managers performing specialized reviews were more confident in their reviews. However, both seniors and managers performing specialized reviews required on average more time than those performing all‐encompassing reviews. Additional analysis suggests that specialized reviewers were also less calibrated. We attribute these results to specialization interfering with auditors' mental model of review. The results su...
Evaluating the SDC Mergers and Acquisitions Database

We compare 20 years of data from Thompson Financial SDC Platinum (SDC)'s Mergers and Acquisitions database with a hand-collected database, providing evidence on the completeness and accuracy of SDC data across time. We find that our hand-collected data is generally more accurate than SDC, but SDC's accuracy and coverage improves over time. Our investigation of discrepancies between the databases finds that SDC is more prone to errors on smaller, high book-to-market acquirers with weak announcement period market responses. Preliminary analyses suggest that this potential bias is not significant, but could affect inferences when examining smaller, high book-to-market firms.
Voluntary Disclosure in a Multi‐Audience Setting: An Empirical Investigation

Theory suggests that voluntary disclosure decisions are a function of conflicting incentives vis‐a`‐vis multiple audiences. However, few opportunities exist to investigate this issue empirically. We identify a setting that offers us such an opportunity: the electric utility industry as it transitions toward deregulation. We consider two types of voluntary disclosures: strategies to protect the firm's existing customer base and plans to exploit emerging opportunities under deregulation. We examine these particular disclosures since they are voluntary, relevant to all sample firms, and convey positive information about the firm's prospects in a deregulated environment. We consider three target audiences: industry regulators, capital market participants, and product market competitors. We find that our disclosure index is negatively associated with the magnitude of utilities' stranded costs in jurisdictions where the stranded cost recovery issue is unresolved, consistent with our predicted regulatory incenti...
Credit Risk Model with Lagged Information

In a structural credit risk model, the credit spread is a function of how far firm value is above the critical level that will cause the firm to default. Previous research has shown that in a theoretical model with periodic information releases, such as quarterly earnings reports, the credit spread will exhibit a cyclical pattern and will tend to be much narrower immediately after a release than is observed empirically. Choi demonstrates that simply allowing information about the firm value to reach the market with a lag is enough to produce reasonable spreads without discrete information releases. Thus, is it the lag rather than the discreteness of announcements that keeps the credit spread at empirically observed levels?
Awareness of SEC Enforcement and Auditor Reporting Decisions

We find that non-Big 4 audit offices with greater awareness of SEC enforcement are more likely to issue first-time going-concern reports to distressed clients; where SEC “awareness” is measured using (i) audit office proximity to SEC regional offices, and (ii) proximity to specific SEC enforcement actions against auditors. We also show that these non-Big 4 audit offices issue more going-concern opinions to clients who do not subsequently fail, indicating a conservative bias that reduces the informativeness of audit reports. This conservative reporting bias is also associated with higher audit fees and higher auditor switching rates. These findings are important because non-Big 4 firms now audit 39 percent of SEC registrants and issue 88 percent of going-concern audit reports. For Big 4 offices, we find some evidence that awareness of SEC enforcement may improve reporting accuracy by reducing Type II errors (failing to issue a going-concern report to a company that fails), although the number of cases is small. This article is protected by copyright. All rights reserved.
Gender Earnings Differentials Among College Administrators

This analysis examines gender pay gap among the top five salaried individuals at private higher education institutions. We find a 13.0 percent average pay disadvantage for women versus men. This pay gap can be decomposed into a 10.4 percent differential owing to differences in the types of institutions and occupations that women hold relative to men and a 2.6 percent unexplained earnings differential.
Mirror neuron research and Adam Smith's concept of sympathy: Three points of correspondence

In The Theory of Moral Sentiments, Adam Smith asserts that humans have an innate interest in the fortunes of other people and desire for sympathy with others. In Smith’s theory, sympathy is an imperfectly reflected combination of emotion and judgment when one observes someone (the agent) in a particular situation, and imagines being that person in that situation. That imagination produces a degree of interconnectedness among individuals. Recent neuroscience research on mirror neurons provides evidence consistent with Smith’s assertion, suggesting that humans have an innate capability to understand the mental states of others at a neural level. A mirror neuron fires both when an agent acts and when an agent observes that action being performed by another; the name derives from the “mirroring” of the action in the brain of the observer. This neural network and the capabilities arising from it have three points of correspondence with important aspects of the Smithian sympathetic process: an agent’s situation as a stimulus or connection between two similar but separate agents, an external perspective on the actions of others, and an innate imaginative capacity that enables an observer to imagine herself as the agent, in the agent’s situation. Both this sympathetic process and the mirror neuron system predispose individuals toward coordination of the expression of their emotions and of their actions. In Smith’s model this decentralized coordination leads to the emergence of social order, bolstered and reinforced by the emergence and evolution of informal and formal institutions grounded in the sympathetic process. Social order grounded in this sympathetic process relies on a sense of interconnectedness and on shared meanings of actions, and the mirror neuron system predisposes humans toward such interconnection.
Ronald Coase and law and economics in Europe

Ronald Coase himself never wrote about law and economics in Europe. Yet many of his insights about the development of the discipline in the United States are extremely useful to our understanding of the methodological and practical challenges faced by European law and economics (as in most civil law jurisdictions). This paper argues that a careful consideration of Coase’s insights might address some of the current limitations.
FLSA Working Hours Reform: Worker Well-Being Effects in an Economic Framework

This article discusses a model developed to predict the effects of recently proposed amendments to the FLSA workweek and overtime provisions. The model contrasts allowing compensatory time for overtime pay for private nonexempt employees to “rights to request” reduced hours. Hours demanded are likely to rise for workers who request comp time, undermining the intention of family-friendliness and alleviating overemployment, unless accompanied by offsetting policies that would prevent the denied use or forced use of comp time and that resurrect some monetary deterrent effect. A unique survey shows that the preference for time over money and comp time is relatively more prevalent among exempt, long hours and women workers; thus, worker welfare is likely better served if comp time were incorporated into an individualized, employee-initiated right to request
An Intertemporal Capital Asset Pricing Model with Owner-Occupied Housing

This article studies portfolio choice and asset pricing in the presence of owner-occupied housing in a continuous time framework. The unique feature of the model is that housing is a consumption good as well as a risky asset. Under general conditions, that is, when the utility function is not Cobb–Douglas and the covariance matrix is not block-diagonal, the model shows that the market portfolio is not mean-variance efficient, and the traditional capital asset pricing model fails. Nonetheless, a conditional linear factor pricing model holds with housing return and market portfolio return as two risk factors. The model also predicts that the nondurable consumption-to-housing ratio (ch) can forecast financial asset returns. The two factor pricing model conditioning on ch yields a good cross-sectional fit for Fama–French 25 portfolios.
Why Do Cities Hoard Cash? Determinants and Implications of Municipal Cash Holdings

ABSTRACT: This study examines the determinants of municipal cash holdings and the implications of holding high levels of cash. The first part of the analysis investigates municipal manager incentives to accumulate cash as part of normal operations. Results indicate that municipalities with a higher variation in revenues, fewer sources of revenues, and higher growth accumulate more cash. Larger governments and those receiving relatively more state revenue accumulate less cash. Further analysis considers whether high levels of cash indicate agency problems, and finds municipalities with high cash holdings spend more on administrative expenses, city manager salaries, and bonuses. I find no evidence that municipalities with excess cash reduce taxes. The presence of staggered councils and councils that are not independent tend to exacerbate excessive cash holdings. These results are consistent with the proposition that municipalities with high cash levels have agency problems relative to those with lower cash ...
Measurement of Market Integration and Arbitrage

We develop a measurement theory of market integration, based on two notions of "integrated markets. " First, two markets cannot be perfectly integrated in any sense if one can construct two portfolios, one from each market, that have identical payoffs but different prices. In that case, the law of one price is violated across the markets. Second, they cannot be integrated in a stronger sense if there are cross-market arbitrage opportunities. Two measures of market integration are developed, respectively reflecting these notions. The smaller the measures, the more closely integrated (in the respective senses) the markets. Among other things, they are interpreted as measuring pricing discrepancy between markets. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.
Secession in International Law and Relations: What Are We Talking About?

“Secession” is a commonly recognized method of state creation, yet exactly what secession entails remains a moot point. International legal instruments fail to provide any definitional and conceptual guidance; scholars adopt divergent definitional approaches, often failing to provide any reasoning to substantiate their positions. This article aims to address the important question of how to define secession in international law and relations. In order to undertake this task it develops a definition based upon etymological, conceptual and international legal principles. By doing so it makes an original contribution to existing secessionist discourses, providing a conceptual and definitional framework for the classification of secessionist state creation.
Being Surprised by the Unsurprising: Earnings Seasonality and Stock Returns

We present evidence consistent with markets failing to properly price information in seasonal earnings patterns. Firms with historically larger earnings in one quarter of the year (“positive seasonality quarters”) have higher returns when those earnings are usually announced. Analysts have more positive forecast errors in positive seasonality quarters, consistent with the returns being driven by mistaken earnings estimates. We show that investors appear to overweight recent lower earnings following positive seasonality quarters, leading to pessimistic forecasts in the subsequent positive seasonality quarter. The returns are not explained by risk-based explanations, firm-specific information, increased volume, or idiosyncratic volatility.Received June 19, 2014; accepted April 25, 2016, by Editor David Hirshleifer.
Estimating the determinants of stock price changes

I develop an approach for estimating the determinants of stock price changes that uses all eligible trade data and other observable parameters of market activity. This approach backs out the unobserved continuous price change distribution from the observable discrete price changes, and does not constrain the determinants to be proportions of the traded bid-ask spread. I show that theoretically impermissible results and skewed estimates of cost components are obtained when the model used for estimating the determinants of stock price changes does not attempt to uncover the mapping between the observed price changes and the underlying unobserved continuous price change process, and does not effectively use all eligible trade data.
Governing and Financing Blended Enterprise

The image of nonprofit and for-profit as dual and exclusive categories is misleadingly simple. This blurring of the boundary between for-profit and nonprofit has gone on for years and appears only to be gaining steam. Yet, traditionally, the law has put organizations to a choice of either the nonprofit or for-profit form of governance. In the first decade of this century, organizational law is beginning to catch up with the boundary-blurring trend. Legislatures are creating new forms for blended enterprise, including several U.S. states’ low-profit limited liability company (the “L3C”) and the community interest company (the “CIC “) in England and Wales. Along with these more formal efforts, at least one self-regulatory scheme provides a framework to fashion a blended form (the “B Corporation”) under traditional state for-profit corporation law. This article describes and compares these forms, evaluating whether they can enhance the governance and finance of blended enterprise.
Alternative Schools of Economic Thought

Alternative schools of economic thought are defined relative to the current mainstream of economic theory. This article examines the path of mainstream economics during the twentieth century and the challenges presented to the mainstream by various alternative schools of economic thinking, such as the desire for relevance of American institutional economics, the emphasis on market process and calculation given by Austrian economics, the role of gendered theorizing examined by feminist economics, and the treatment of uncertainty offered by post-Keynesian Economics.
Entitled to Work: Urban Property Rights and Labor Supply in Peru

This brief summarizes the results of a gender impact evaluation study, entitled Entitled to work : urban property rights and labor supply in Peru, new legal rights were issued in 1996; project teams providing titling service through 2003, in Peru. The study observed that between 1996 and 2003, the Peruvian government issued property titles to over 1.2 million urban households, the largest titling program targeted at urban squatters in the developing world. This paper examines the labor market effects of increases in tenure security resulting from the program. Pre-program squatters in program neighborhoods were significantly more likely to report improved tenure security, by 60 percent. Similarly, program participants were 18.8 percentage points less likely to report a high likelihood of eviction or invasion and 18.8 percentage points more likely to report that their dwelling was currently very secure from eviction or invasion. The likelihood of working inside the home significantly falls by 11.6 percentage points for the average squatter family with two program periods.
Karl Popper and Conspiracy Theories in Polish Political Thought

Abstract: Over the last century, Polish national discourse and political culture have produced an uncommonly high incidence of conspiracy theories. A similar tendency can be shown to occur among expatriates, even those one or two generations removed from the home land. Two hundred fifty years of partitions between hostile neighbors resulting in deprivation of a national identity, along with systematic oppression by the occupants’ secret police, and a tradition of uprisings and mass emigration recurring generation after generation account for some of the propensity for conspiracy theories. Karl Raimund Popper recognized conspiracy theories as psychologically anamorphous phenomena based on flawed cognitive patterns and misguided axiomatic beliefs that the more consequential an event, the less likely it is to be random or unintended. This paper examines Polish evidence of Popper’s diagnosis of a widespread aversion to attributing significant events to good or bad luck and of an assumption of an underlying intentional order. Many conspiracy theories go wrong not by mistakenly assuming intentional actors but their identity, motives, or degree of coordination. The common denominator of all conspiracy theories is a misjudgment of the forces of randomness, invisible hand mechanisms, or accidentally disproportionate consequences of relatively minor causes and/or overestimation of the possibility of maintaining control and secrecy of conspiracies in open societies. While not a universal panacea, simple interest analysis can dispel the notion of conspiracy but it can also form part of the misleading theory itself. Keywords: Poland, Karl Popper, Conspiracy Theories, Politics, Rhetoric and Communication, Discourse.
The Dogs That Did Not Bark: The Silence of the Legal Academy during World War II

During World War II, the legal academy was virtually uncritical of the government’s conduct of the war, despite some obvious domestic abuses of civil rights, such as the internment of Japanese-Americans. This silence has largely been ignored in the literature about the history of legal education. This Article argues that there are many strands of causation for this silence. On an obvious level, World War II was a popular war fought against a fascist threat, and left-leaning academics generally supported the war. On a less obvious level, law school enrollment plummeted during the war, and the numbers of full-time law professors dropped by half. Of those professors “laid off” during the war, many took employment in government agencies and thus effectively silenced themselves. Finally, the American Association of Law Schools had only adopted a strong position on academic freedom and tenure in 1940. The commitment to academic freedom and tenure was insecure in many institutions and was only weakened by the severe economic strain of the war. To illustrate the effect of these larger forces, this Article tells the stories of five professors who criticized domestic policy during the war and the institutional consequences of their dissent. Of those professors, only one - a tenured professor at New York University - was fired during the war. While the basic building blocks of legal academies are the same today as they were in World War II, other factors such as strong institutional commitments to academic freedom and tenure, a robust First Amendment, and economic prosperity have significantly changed the roles that law professors are empowered to play in society, most significantly as the watchdogs of government.
Taking Stock of Newspapers and Their Future

In this essay, we will touch upon many subjects that are contributing to the changing face of daily newspapers in the United States. We begin with a brief and conclusory definition of editorial freedom in news, the foundation of journalism, and the key to its educational function in the news setting. We will then turn to markets, technology, economics, organization of the news firm, operation of the newsroom, and the changing definition of news. Our purpose is to identify deep changes that are occurring in the nature and institutions of news, changes that will continue to evolve in un-foreseeable but perhaps controllable ways as the Twenty-first Century unfolds.
Restraining the Genuine Homo Economicus: Why the Economy Cannot Be Divorced from Its Governance

The Homo economicus of traditional economics is far from being completely self-interested, rational, or as individualistic as he is purported to be; he will haggle to death over price but will not take what he wants by force. Implicitly, he is assumed to behave ruthlessly within a well-defined bubble of sainthood. Based on a simple model, I first examine what occurs when this assumption is relaxed and genuine, amoral Homo economici interact. Productivity can be inversely related to compensation; a longer shadow of the future can intensify conflict; and more competition among providers of protection reduces welfare. The patently inefficient outcomes that follow call for restraining self-interest, for finding ways to govern markets. I then review some of the different ways of creating restraints, from the traditional social contract, to the hierarchical domination of kings and lords, to modern forms of governance. Checks and balances, wider representation, the bureaucratic form of organization, and other ingredients of modern governance can partly be thought of as providing restraints to the dark side of self-interest. Though highly imperfect, these restraints are better than the alternative, which typically involves autocratic, amateurish, and corrupt rule. Then, thinking of most problems in terms of a first-best economic model is practically and scientifically misguided.
Corporate Citizenship: The Case for a New Corporate Governance Model

© 2004 Center for Business Ethics at Bentley College. Published by Blackwell Publishing, 350 Main Street, Malden, MA 02148, USA, and 9600 Garsington Road, Oxford OX4 2DQ, UK. Blackwell Publishing, Ltd. Oxford, UK ASR usiness and Society Review 0045-3609 © 2004 Ce ter f r Busin ss Ethics at Bentley College 1 9 3 rigi al Article U INESS and SOCIETY R VIEW THOMA A. HEMPHI L Corporate Citizenship: The Case for a New Corporate Governance Model
The Argument from Transnational Effects I: Representing Outsiders through Freedom of Movement

Earlier versions of this article were presented at a conference at the Berlin Institute for Advanced Study, at an in‐house faculty workshop at the University of Iowa and as part of the International Legal Theory Colloquium at New York University Law School. I owe a debt of gratitude to colleagues who provided me with critical feedback, in particular to Arthur Bonfield, Armin von Bogdandy, Ann Estin, Herbert Hovenkamp, Benedict Kingsbury, Mattias Kumm, Todd E. Pettys and Joseph Weiler. I should also like to acknowledge how much I benefited from having been part of a group of ‘constitutionalists’ that was resident at the Berlin Institute during the academic year of 2007/08. Attending a weekly conversation with Petra Dobner, Dieter Grimm, Bogdan Iancu, Martin Loughlin, Fritz W. Scharpf, Gunther Teubner and Rainer Wahl has been highly conducive to the clarification of my constitutional ideas.
Bank Borrowers and Loan Sales: New Evidence on the Uniqueness of Bank Loans*

This article examines the information content of the sale announcement of a borrower’s loans by its lending bank. We find significant negative stock returns for the borrower on the loan sale announcement, particularly for subpar loan sales, where the bank’s information advantage is greatest. Further, a large proportion of these borrowers file for bankruptcy after the loan sale. The evidence supports the hypothesis that the news of a bank loan sale conveys negative certification, which is validated by the subsequent performance of the firms whose loans are sold. We also find that the selling banks are not significantly affected.
The determinants of board structure.

Abstract Using a comprehensive sample of nearly 7,000 firms from 1990 to 2004, we examine the corporate board structure, trends, and determinants. Guided by recent theoretical work, we find that board structure across firms is consistent with the costs and benefits of the board's monitoring and advising roles. Our models explain as much as 45% of the observed variation in board structure. Further, small and large firms have dramatically different board structures. For example, board size fell in the 1990s for large firms, a trend that reversed at the time of mandated reforms, while board size was relatively flat for small and medium-sized firms.