cssi/SciSciGPT-SciSciNet huggingface dataset:
Standing for (and up to) Separation of Powers

The U.S. Constitution requires federal agencies to comply with separation-of-powers (or structural) safeguards, such as by obtaining valid appointments, exercising certain limited powers, and being sufficiently subject to the President’s control. Who can best protect these safeguards? A growing number of scholars call for allowing only the political branches — Congress and the President — to defend them. These scholars would limit or end judicial review because private judicial challenges are aberrant to justiciability doctrine and lead courts to meddle in minor matters that rarely effect regulatory outcomes.This Article defends the right of private parties to assert justiciable structural causes of action, arguing that institutional, constitutional, and doctrinal limitations preclude the branches from serving as structural protectors. Indeed, this Article concludes, contrary to recent scholarship, that private claims fit easily within established justiciability doctrines. To address legitimate concerns over utility and judicial intermeddling, this Article argues that courts should confront the underlying doctrine directly by adopting a functional separation-of-powers doctrine with meaningful remedies. Doing so will limit successful claims to only the most important and thereby appropriately balance the political branches’ discretion under the Constitution to design the administrative state with useful judicial oversight.
Central-Bank Credibility: Why Do We Care? How Do We Build It?

Central bank credibility plays a pivotal role in much of the modern literature on monetary policy, yet it is difficult to measure or even assess objectively. A survey of central bankers was conducted to determine their attitudes on two important issues: why credibility matters, and how credibility can be built. The central bankers' answers are compared with the responses of NBER-affiliated macro and monetary economists. The two groups agree much more than they disagree. They are particularly united in their evaluations of ways to make a central bank credible -- assigning high ratings to the central bank's track record and low ratings to theoretical ideas like precommitment and incentive-compatible contracts.
Portfolio Value-at-Risk with Heavy-Tailed Risk Factors

This paper develops efficient methods for computing portfolio value-at-risk (VAR) when the underlying risk factors have a heavy-tailed distribution. In modeling heavy tails, we focus on multivariate t distributions and some extensions thereof. We develop two methods for VAR calculation that exploit a quadratic approximation to the portfolio loss, such as the delta-gamma approximation. In the first method, we derive the characteristic function of the quadratic approximation and then use numerical transform inversion to approximate the portfolio loss distribution. Because the quadratic approximation may not always yield accurate VAR estimates, we also develop a low variance Monte Carlo method. This method uses the quadratic approximation to guide the selection of an effective importance sampling distribution that samples risk factors so that large losses occur more often. Variance is further reduced by combining the importance sampling with stratified sampling. Numerical results on a variety of test portfolios indicate that large variance reductions are typically obtained. Both methods developed in this paper overcome difficulties associated with VAR calculation with heavy-tailed risk factors. The Monte Carlo method also extends to the problem of estimating the conditional excess, sometimes known as the conditional VAR.
Estimating Causal Installed-Base Effects: A Bias-Correction Approach:

Abstract New empirical models of consumer demand that incorporate social effects seek to measure the causal effect of past adopter's behavior—the “installed-base”—on current adoption behavior. Identifying such causal effects is challenging due to several alternative confounds that generate correlation in agents' actions. In the absence of experimental variation, a preferred solution has been to control for these spurious correlations using a rich specification of fixed effects. The authors show that fixedeffects estimators of this sort are inconsistent in the presence of installed-base effects; in simulations, random-effects specifications perform even worse. The analysis reveals the tension the applied empiricist faces in this area: a rich control for unobservables increases the credibility of the reported causal effects, but the incorporation of these controls introduces biases of a new kind in this class of models. The authors present two solutions: a modified version of an instrumental variable approa...
Executioner Identities: Toward Recognizing a Right To Know Who Is Hiding Beneath the Hood

The doctor had more than twenty malpractice suits filed against him.1 Two hospitals had revoked his privileges.2 He testified that he had dyslexia and sometimes confused drug dosages.3 This same doctor also supervised the lethal injections of fifty-four inmates in Missouri over a decade.4 For ten years, the public, the press, and the condemned inmates themselves did not know about the supervising executioner’s qualifications in Missouri.5 In a federal lawsuit challenging the state’s implementation of lethal injection, the Department of Corrections refused to reveal any information about execution team members until a magistrate judge issued a protective order and required team members to answer interrogatories.6 Once the case reached the district court, the judge did not allow testimony because of time constraints.7 The doctor whose problem-plagued history
Inheritance Equity: Reforming the Inheritance Penalties Facing Children in Non-Traditional Families

This Article examines how more than 50% of children living today may be disadvantaged by 1950s era inheritance laws that privilege and protect only those children living in nuclear families with their biological parents. Because so many children today are living in blended families — single-parent families, lesbian, gay, bisexual, transgender, or queer/questioning (LGBTQ) families, or are living with relatives — their right to inherit from the persons who function as their parents are severely limited by most state probate codes, even though they would likely be entitled to child support under the parent-child definitions of most of those states' family law codes. In the unusual case of second-parent adoptions by the partner of a biological parent, many children will be cut off from being able to inherit from their biological parent, which is a truly unanticipated consequence of the “fresh start” provision of most probate codes that delineate the rights of adopted children. This article explores the vast scope of the inheritance penalty, including the history of equitable adoption doctrines and attitudes about parenting. It includes model statutory language to resolve some of the myriad disabilities in these probate codes and a chart detailing how the adoption and inheritance laws of all fifty states interact to create the inheritance penalty.
The Natural Complexity of Patent Eligibility

It has long been assumed that the doctrine of patent eligibility’s prohibition of patents on “laws of nature,” “natural phenomena,” and “products of nature” rests on legalistic interpretations of those terms. But there is good reason to doubt this assumption. Since the doctrine’s inception, the Supreme Court has yet to provide any framework, formula, or factors explaining these “natural” terms. Rather, the Court has increasingly fixated on a list of scientific tropes, such as gravity, the heat of the Sun, and extracted metals, that it believes are true examples of “natural laws,” “phenomena,” and “products.”An actual examination of scientific philosophy, however, demonstrates that these concepts are anything but true examples of “natural laws,” “phenomena,” and “products.” And one branch of scientific philosophy in particular, natural complexity, focuses on why such terms are ultimately unworkable today. This disconnect between patent eligibility’s appeal to science and natural complexity’s agnosticism of patent eligibility’s terms explains some of the problems patentable eligibility faces today in applying the terms “laws of nature,” “natural phenomena” and “products of nature” to current technologies. Interestingly, the solution to these difficulties may lie in recognizing that the doctrine of patent eligibility is, itself, complex: that rather than breaking down its analysis into cognitively easier subparts, it operates under the burden of a complicated and unworkable whole. Solutions to analogous scientific problems revolve around the strategies of “decomposition” and “localization,” i.e., “decomposing” a system into cognitively manageable subparts and “localizing” those subparts to functions of the overall system. In this way, researchers can develop a coherent description of the system as a whole. While this may appear inapplicable to the law, other complex areas of jurisprudence use this methodology to break down high-order, generalized questions into separate “factors” or “prongs” that map to the law’s substantive purposes. Harnessing decomposition and localization for patent eligibility — rather than attempting to resolve the grander question of what a “natural law” is — may go a long way in developing a coherent, legalistic, and yet simple framework to the century-and-a-half old doctrine.
The Balance Sheet as an Earnings Management Constraint

The balance sheet accumulates the effects of previous accounting choices, so the level of net assets partly reflects the extent of previous earnings management. We predict that managers' ability to optimistically bias earnings decreases with the extent to which the balance sheet overstates net assets relative to a neutral application of GAAP. To test this prediction, we examine the likelihood of reporting various earnings surprises for 3,649 firms during 1993–1999. Consistent with our prediction, we find that the likelihood of reporting larger positive or smaller negative earnings surprises decreases with our proxy for overstated net asset values.
On the dynamics and severity of bank runs: An experimental study

Article history: This paper presents an experimental investigation of the factors that affect the dynamics and severity of bank runs. Our experiments demonstrate that the more information laboratory economic agents can expect to learn about the crisis as it develops, the more willing they are to restrain themselves from withdrawing their funds once a crisis occurs. Furthermore, our results indicate that the presence of insiders, who know the quality of the bank, significantly affects the dynamics of bank runs and helps mitigate their severity. We also show that deposit insurance, even of a limited type, can help diminish the severity of bank runs. Published by Elsevier Inc.
Pay It Forward? Law and the Problem of Restricted-Spending Philanthropy

American foundations and other philanthropic giving entities hold about $1 trillion in investment assets, and that figure continues to grow every year. Even as urgent contemporary needs go unmet, philanthropic organizations spend only a tiny fraction of their wealth each year, mostly due to restrictive terms in contracts between donors and firms limiting the rate at which donations can be distributed. Law has played a critical role in underwriting and encouraging this buildup of philanthropic wealth. For instance, contributors can typically take a full tax deduction for the value of their contributions today, no matter when the foundation spends their money, and pay no tax on the investment earnings the organization reaps in the meantime. What, if anything, justifies public support for “restricted spending” charity? This Article offers the first comprehensive assessment of that question and supplies original empirical evidence on several key aspects of it. I argue that restricted spending sacrifices crucial information, leaves superior opportunities on the table, and on average transfers funds to times when they are less useful. While there is a place for large and long Professor of Law, Georgetown University Law Center. I am grateful for helpful comments from Bill Bagley, Tom Brennan, Neil Buchanan, Roger Colinvaux, John Colombo, Vic Fleischer, Dan Halperin, Louis Kaplow, Michael Klausner, Don Langevoort, Ben Leff, Yair Listokin, Ray Madoff, Jim Repetti, Diane Ring, Natalya Shnitser, Josh Teitelbaum, Mark Wolfson, and attendees of presentations at the Forum on Effective Philanthropy, the University of Southern California Sol Price School of Public Policy, the National Tax Association, Georgetown University Law Center, and Boston College Law School. Washington University Open Scholarship 1144 WASHINGTON UNIVERSITY LAW REVIEW [VOL. 93:1143 lived philanthropic organizations in American society, that role does not require public support for restricted spending. As long as foundations can demonstrate their value to new donors, they will continue to thrive. I set out a series of policy recommendations aimed at better reconciling nonprofit law and the principles that justify it. I support my claims with new evidence drawn from a data set of over 200,000 firm-year observations of private foundations. For example, I find that foundations earn about twice as much money per year as in earlier studies funded by foundation-industry lobbyists and that they are growing three times faster than those earlier studies suggested. This finding implies that the law could require a much higher annual “payout” from foundations. I also find that new laws introduced in about a dozen states since 2006 have significantly slowed foundation spending in the enacting states. Last, I offer simulations of several policy proposals for making foundations more effective at fighting recessions.
Political Justice and Tax Policy: The Social Welfare Organization Case

In addition to valuing whether a tax policy is equitable, efficient, and administrable, I argue we should ask if a tax policy is politically just. Others have made a similar case for valuing political justice as democracy in implementing just tax policy. I join that call and highlight why it matters in one arena – tax exemption. I argue that politically just tax policy does the least harm to the democratic functioning of our government and may ideally enhance it. I argue that our right to an equal voice in collective decision making is the most fundamental value of political justice. To test this case, I evaluate our choice to exempt ‘social welfare organizations’ from the U.S. income tax. In addition to efficiency and equity, I also ask whether the policy is politically just in a democratic sense. I examine three models of democratic justice: liberal, republican, and deliberative. In making the democratic case I try to find commonalities among the three in order to further what an agreed upon notion of democratic justice might look like in the tax context. I contend that the notion of democratic justice must exist at the substantive level of Code. This Code level application demonstrates that the typical criteria of efficiency and fairness do not provide sufficient criteria to evaluate the justice of tax-exempt policy. There are likely significant other parts of income tax policy that need to be considered from the value of political justice as democracy as well.
The Future of Legal Education Reform

The history of the legal profession’s self-regulation during self-identified crisis times (such as the present) is not a happy one. The profession has resisted change. When it has instituted change, such change has been directed not at the existing members of the profession, but at new entrants. Mostly, the change that has come has been forced by the influence of society, culture, economics, and globalization — not by the profession itself. These change agents include Watergate, communist infiltration, the arrival of waves of immigrants, the litigation explosion, the civility crisis, and the current economic crisis that blends with dramatic changes in technology, communications, and globalization. In every instance the profession has held fast to its history and its ways long after those ways have become anachronistic. The profession seems to repeat the same question in response to every crisis: How can we stay even more the same than we already are? Legal education has fared little better in this mode.
EXPRESSIVE ASSOCIATION AFTER DALE

The right to join with other people to promote a particular outlook, known as the right of expressive association, is a necessary adjunct to the right of freedom of speech, which is protected by the First Amendment of the United States Constitution. In Boy Scouts of America v. Dale, the United States Supreme Court found that the Boy Scouts of America had a First Amendment expressive association right to exclude a homosexual adult volunteer. Dale is likely to prove to be one of the most important First Amendment cases of recent years, because the Court enforced a broad right of expressive association against the competing claims of an antidiscrimination law. The right to expressive association had languished in obscurity for more than two decades after the Supreme Court articulated it in the late 1950s and early 1960s in the course of protecting civil rights activists from racist Southern governments. Controversy over constitutional protection of expressive association arose in the 1980s, when private associations claimed that it protected their right to discriminate when necessary to pursue the associations’ goals. The Supreme Court seemed aghast that the expressive association right was being used as a tool of those who would seek to use its protection of their associative status in order to discriminate. In a series of opinions in the mid to late 1980s, the Court both narrowly defined the circumstances in which expressive association rights are impinged, and suggested that antidiscrimination laws are always “compelling government interests” sufficient to override these rights. The right of expressive association had been significantly weakened. Dale, however, dramatically revived the right of expressive association. The Court found that the Boy Scouts had an expressive association right to exclude gay scoutmasters even though the Scouts’ anti-homosexual activity policy was neither wellpublicized nor especially central to its mission. Moreover, the Court rejected New Jersey’s claim that the law was justified by the state’s compelling interest in eradicating discrimination against homosexuals. The essay examines the right of expressive association and the consequences of its reinvigoration by the Supreme Court in Dale. Part I recounts the ups and downs of the right from its inception in civil rights cases, to its low ebb in the 1980s, to its reinvigoration in Dale. Part II discusses some of the scholarly commentary on Dale and concludes that the right to expressive association after Dale will continue to be a broad one, with some limitations. Part III discusses some of the post-Dale decisions that support the interpretation of Dale as expounding a broad-based expressive association right fully applicable to a variety of situations. Finally, Part IV looks at some of the untapped potential uses of the right. In particular, Dale will often shield religious associations from intrusive antidiscrimination laws.
Plausibly exogenous causes of economic freedom

A large literature has emerged investigating the origins of the institutions of economic freedom. While some literature has used impressive identification strategies to tackle this question, findings as a whole are typically circumscribed in their identification. This paper considers a series of variables that are reasonably thought of as exogenous, namely, legal origins and a series of environmental variables. It then compares their effects on economic freedom to the lagged relationships of education, democracy, and civil society with economic freedom. The historical prevalence of pathogens at first appears to be a strong determinant of economic freedom, but it is tentatively concluded that this occurs through the conduit of education, with lagged education having a strongly positive relationship with economic freedom. We also find that the natural log of the size of a country has a negative effect on economic freedom. We separately observe several other tertiary or less robust results in the course of the analysis found herein.
Analyzing the economic efficiency of eBay-like online reputation reporting mechanisms

This paper introduces a model for analyzing marketplaces, such as eBay, which rely on binary reputation mechanisms for quality signaling and quality control. In our model sellers keep their actual quality private and choose what quality to advertise. The reputation mechanism is primarily used to determine whether sellers advertise truthfully. Buyers may exercise some leniency when rating sellers, which needs to be compensated by corresponding strictness when judging sellers'feedback profiles. It is shown that, the more lenient buyers are when rating sellers, the more likely it is that sellers will find it optimal to settle down to steady-state quality levels, as opposed to oscillating between good quality and bad quality. Furthermore, the fairness of the market outcome is determined by the relationship between rating leniency and strictness when assessing a seller's feedback profile. If buyers judge sellers too strictly (relative to how leniently they rate) then, at steady state, sellers will be forced to understate their true quality. On the other hand, if buyers judge too leniently then sellers can get away with consistently overstating their true quality. An optimal judgment rule, which results in outcomes where at steady state buyers accurately estimate the true quality of sellers, is analytically derived. However, it is argued that this optimal rule depends on several system parameters, which are difficult to estimate from the information that marketplaces, such as eBay, currently make available to their members. It is therefore questionable to what extent unsophisticated buyers are capable of deriving and applying it correctly in actual settings.
Unmistakably Clear: Human Rights, the Right to Representation, and Remedial Voting Rights of People of Color

The Author critiques the Supreme Court’s analysis in its Shelby County v. Holder decision, which found the preclearance requirement of the Voting Rights Act unconstitutional by applying a disparate treatment analysis to how States were treated under the Act. Such a reading of the Act makes a number of tacit and explicit assumptions with regard to the choice by the Federal Government and by the States of whose rights governmental actors must protect. The Court reached its conclusion by decontextualizing the Civil Rights movement and the Voting Rights Act from decolonization and post-World War II expressions of human rights, a time in which there was a move toward greater global recognition that the “other” has rights that are enforceable based on recognition of individual human equality. In this Essay, the Author considers the context of the Fifteenth Amendment and its work in overturning prior jurisprudence that indicated a divorcing of constitutional protections from the African-American population. The Author then turns to the context of the Voting Rights Act of 1965 and the connection between U.S. rights-protective legislation and a global shift toward rights-protective treatises and laws. Then the Author juxtaposes the positivist stance of international law with the current Court’s jurisprudential posture of seeking congressional clarification and justification of rights above all else, even in the context of civil and human rights. Finally, the Author concludes that without positivist interpretations that have permeated U.S. civil rights legislation and jurisprudence in the past, new voting rights legislation can achieve neither its domestic nor global potential.
The Economic Theory of Nuisance Law and Implications for Environmental Regulation

I explore the economic structure of nuisance law as a mechanism for regulating environmental interferences and propose a modernized enforcement regime. The modern regime would retain public enforcement primarily in identifying environmental harms and as a backstop for private enforcement.
How much is too much? The limits to generous treatment of stakeholders

Abstract Firms must allocate some minimum amount of value to stakeholders in order to retain access to the resources they provide. Stakeholder theory suggests managers optimize firm-level performance by allocating more than this minimum amount. However, how much is too much? This article addresses the misleading notion that more is always better when it comes to the treatment of stakeholders and, in doing so, provides needed refinement of the boundary of stakeholder theory's predictions. The upside for managers is guidance in distinguishing between the types of value-allocating behaviors that will lead to greater value creation in their firms and actions that are likely to reduce value overall.
Does quality matter in local consumption amenities? An empirical investigation with Yelp ☆

Abstract The possibility that local consumption amenities provided by bars, restaurants, and other retail services improve neighborhood or city attractiveness has received increasing attention in the literature. Empirical research thus far has focused on the number of establishments in an area. This paper proposes and tests a method for differentiating consumption amenities along a quality dimension, based on either consumer ratings or price estimates from Yelp.com. Appealing to the implicit market model of Rosen (1974), consumption amenity is capitalized in the value of nearby housing. The results demonstrate that both the quantity and quality aspects of consumption amenities matter, and that consumer ratings are more informative about unobservable restaurant amenity than price estimates. Furthermore, comparisons between the results for the pre– and post-Yelp periods show that such capitalization differentials are more significant when information on quality is readily available to and widely used by the public. The method used in this paper to measure the quality of consumption amenities could be applied to other private retail businesses or even local public goods.
Using earnings conference calls to identify analysts with superior private information

We examine the extent to which analysts who participate in earnings conference calls by asking questions possess superior private information relative to analysts who do not ask questions. Using a large sample of earnings conference call transcripts over the period 2002–2005, we find that annual earnings forecasts issued immediately after a conference call are both more accurate and timelier for participating analysts relative to nonparticipating analysts. These results hold after controlling for observable analyst characteristics, suggesting conference call participation can serve as a mechanism to identify analysts possessing superior private information. The economic magnitude of the superior private information contained in participating analyst forecasts is small but comparable with magnitudes reported in prior studies with respect to other analyst characteristics. Our mediation analysis does not support the notion that the superior private information stems exclusively from the information received during the call. Therefore, from a regulatory stand point, our results suggest that regulatory intervention to allow for equal participation during conference calls may be unwarranted.
Model Selection Using Database Characteristics: Developing a Classification Tree for Longitudinal Incidence Data

When managers and researchers encounter a data set, they typically ask two key questions: 1 Which model from a candidate set should I use? And 2 if I use a particular model, when is it going to likely work well for my business goal? This research addresses those two questions and provides a rule, i.e., a decision tree, for data analysts to portend the “winning model” before having to fit any of them for longitudinal incidence data. We characterize data sets based on managerially relevant and easy-to-compute summary statistics, and we use classification techniques from machine learning to provide a decision tree that recommends when to use which model. By doing the “legwork” of obtaining this decision tree for model selection, we provide a time-saving tool to analysts. We illustrate this method for a common marketing problem i.e., forecasting repeat purchasing incidence for a cohort of new customers and demonstrate the method's ability to discriminate among an integrated family of a hidden Markov model HMM and its constrained variants. We observe a strong ability for data set characteristics to guide the choice of the most appropriate model, and we observe that some model features e.g., the “back-and-forth” migration between latent states are more important to accommodate than are others e.g., the inclusion of an “off” state with no activity. We also demonstrate the method's broad potential by providing a general “recipe” for researchers to replicate this kind of model classification task in other managerial contexts outside of repeat purchasing incidence data and the HMM framework.
There’s Something in a Name: Value Relevance of Congruent Ticker Symbols

Choosing assets for their portfolios is a complex decision, and investors, endowed with limited information processing capacity are influenced by various psychological factors. One such factor is investors’ processing fluency with the firm’s stock. In this paper, we introduce the idea of congruent ticker symbol, defined as whether or not the firm’s ticker symbol is similar to its corporate name (e.g., DELL for Dell, Inc.) Further, we propose that a firm’s congruent ticker symbol, in conjunction with other firm characteristics, will increase investors’ processing fluency with its stock and, therefore, affect its intangible value. We consider the firm’s size, performance, advertising, and distribution presence as firm characteristics that will interact with congruent ticker symbol to affect its intangible value. Data from 181 publicly listed US retailers between 1994 and 2006 strongly support the hypotheses relating the contingent effects of congruent ticker symbols to intangible value. While, firms’ congruent ticker symbols do not independently increase their intangible values, they do so, in conjunction with their performance, advertising, and distribution presence. For marketing theory, congruent ticker symbols emerge as contingent intangible market-based assets that create enduring shareholder value with other firm characteristics. For managerial practice, the findings offer guidance on ticker symbol-naming strategies that can increase shareholder value.
Cocycle enhancements of psyquandle counting invariants

We bring cocycle enhancement theory to the case of psyquandles. Analogously to our previous work on virtual biquandle cocycle enhancements, we define enhancements of the psyquandle counting invaria...
Are 100 Ensemble Members Enough to Capture the Remote Atmospheric Response to +2°C Arctic Sea Ice Loss?

Author(s): Peings, Y; Labe, ZM; Magnusdottir, G | Abstract: This study presents results from the Polar Amplification Multimodel Intercomparison Project (PAMIP) single-year time-slice experiments that aim to isolate the atmospheric response to Arctic sea ice loss at global warming levels of 128C. Using two general circulation models (GCMs), the ensemble size is increased up to 300 ensemble members, beyond the recommended 100 members. After partitioning the response in groups of 100 ensemble members, the reproducibility of the results is evaluated, with a focus on the response of the midlatitude jet streams in the North Atlantic and North Pacific. Both atmosphere-only and coupled ocean–atmosphere PAMIP experiments are analyzed. Substantial differences in the midlatitude response are found among the different experiment subsets, suggesting that 100-member ensembles are still significantly influenced by internal variability, which can mislead conclusions. Despite an overall stronger response, the coupled ocean–atmosphere runs exhibit greater spread due to additional ENSO-related internal variability when the ocean is interactive. The lack of consistency in the response is true for anomalies that are statistically significant according to Student’s t and false discovery rate tests. This is problematic for the multimodel assessment of the response, as some of the spread may be attributed to different model sensitivities whereas it is due to internal variability. We propose a method to overcome this consistency issue that allows for more robust conclusions when only 100 ensemble members are used.
Unsupervised Meta-Learning through Latent-Space Interpolation in Generative Models

Several recently proposed unsupervised meta-learning approaches rely on synthetic meta-tasks created using techniques such as random selection, clustering and/or augmentation. In this work, we describe a novel approach that generates meta-tasks using generative models. The proposed family of algorithms generate pairs of in-class and out-of-class samples from the latent space in a principled way, allowing us to create synthetic classes forming the training and validation data of a meta-task. We find that the proposed approach, LAtent Space Interpolation Unsupervised Meta-learning (LASIUM), outperforms or is competitive with current unsupervised learning baselines on few-shot classification tasks on the most widely used benchmark datasets.
Identifying Dehn functions of Bestvina–Brady groups from their defining graphs

Let $$\Gamma $$ be a finite simplicial graph such that the flag complex on $$\Gamma $$ is a 2-dimensional triangulated disk. We show that with some assumptions, the Dehn function of the associated Bestvina–Brady group is either quadratic, cubic, or quartic. Furthermore, we can identify the Dehn function from the defining graph $$\Gamma $$ .
ARXON : A Framework for Approximate Communication Over Photonic Networks-on-Chip

The approximate computing paradigm advocates for relaxing accuracy goals in applications to improve energy-efficiency and performance. Recently, this paradigm has been explored to improve the energy-efficiency of silicon photonic networks-on-chip (PNoCs). Silicon photonic interconnects suffer from high power dissipation because of laser sources, which generate carrier wavelengths, and tuning power required for regulating photonic devices under different uncertainties. In this article, we propose a framework called AppRoXimation framework for On-chip photonic Networks ( ARXON ) to reduce such power dissipation overhead by enabling intelligent and aggressive approximation during communication over silicon photonic links in PNoCs. Our framework reduces laser and tuning-power overhead while intelligently approximating communication, such that application output quality is not distorted beyond an acceptable limit. Simulation results show that our framework can achieve up to 56.4% lower laser power consumption and up to 23.8% better energy-efficiency than the best-known prior work on approximate communication with silicon photonic interconnects and for the same application output quality.
Parallelized Kalman-Filter-Based Reconstruction of Particle Tracks on Many-Core Processors and GPUs

For over a decade now, physical and energy constraints have limited clock speed improvements in commodity microprocessors. Instead, chipmakers have been pushed into producing lower-power, multi-core processors such as Graphical Processing Units (GPU), ARM CPUs, and Intel MICs. Broad-based efforts from manufacturers and developers have been devoted to making these processors user-friendly enough to perform general computations. However, extracting performance from a larger number of cores, as well as specialized vector or SIMD units, requires special care in algorithm design and code optimization. One of the most computationally challenging problems in high-energy particle experiments is finding and fitting the charged-particle tracks during event reconstruction. This is expected to become by far the dominant problem at the High-Luminosity Large Hadron Collider (HL-LHC), for example. Today the most common track finding methods are those based on the Kalman filter. Experience with Kalman techniques on real tracking detector systems has shown that they are robust and provide high physics performance. This is why they are currently in use at the LHC, both in the trigger and offine. Previously we reported on the significant parallel speedups that resulted from our investigations to adapt Kalman filters to track fitting and track building on Intel Xeon and Xeon Phi. Here, we discuss our progresses toward the understanding of these processors and the new developments to port the Kalman filter to NVIDIA GPUs.
Relative entropy and the Pinsker product formula for sofic groups

We continue our study of the outer Pinsker factor for probability measure-preserving actions of sofic groups. Using the notion of doubly quenched convergence developed by Austin, we prove that in many cases the outer Pinsker factor of a product action is the product of the outer Pinsker factors. Our results are parallel to those of Seward for Rohklin entropy. We use these Pinsker products formulas to show that for many actions of a sofic group G on X where X is a compact group and the action is by automorphism, the (measurable) outer Pinsker factor of the action of G on X is given as a quotient by a G-invariant, closed, normal subgroup. We use our results to show that if G is sofic and f in M_{n}(Z(G)) is invertible as a convolution operator, then the action of G on the Pontryagin dual of \Z(G)^{\oplus n}/\Z(G)^{\oplus n}f has completely positive measure-theoretic entropy with respect to the Haar measure. This last application requires our previous work connecting topological entropy in the presence as defined by Li-Liang to measure-theoretic entropy in the presence (implicitly defined by Kerr) for actions on compact groups. In particular, we need our previous formulation of measure-theoretic entropy in the presence in terms of a given topological model.
Wnt-Dependent Activation of ERK Mediates Repression of Chondrocyte Fate during Calvarial Development

Wnt signaling regulates cell fate decisions in diverse contexts during development, and loss of Wnt signaling in the cranial mesenchyme results in a robust and binary cell fate switch from cranial bone to ectopic cartilage. The Extracellular signal-regulated protein kinase 1 and 2 (ERK1/2) and Wnt signaling pathways are activated during calvarial osteoblast cell fate selection. Here, we test the hypothesis that ERK signaling is a mediator of Wnt-dependent cell fate decisions in the cranial mesenchyme. First, we show that loss of Erk1/2 in the cranial mesenchyme results in a diminished domain of osteoblast marker expression and increased expression of cartilage fate markers and ectopic cartilage formation in the frontal bone primordia. Second, we show that mesenchyme Wnt/β-catenin signaling and Wntless are required for ERK activation in calvarial osteoblasts. Third, we demonstrate that Wnt and ERK signaling pathways function together to repress SOX9 expression in mouse cranial mesenchyme. Our results demonstrate an interaction between the Wnt and ERK signaling pathways in regulating lineage selection in a subset of calvarial cells and provide new insights into Wnt-dependent cell fate decisions.
Efficient Computation and Analysis of Distributional Shapley Values

Distributional data Shapley value (DShapley) has recently been proposed as a principled framework to quantify the contribution of individual datum in machine learning. DShapley develops the foundational game theory concept of Shapley values into a statistical framework and can be applied to identify data points that are useful (or harmful) to a learning algorithm. Estimating DShapley is computationally expensive, however, and this can be a major challenge to using it in practice. Moreover, there has been little mathematical analyses of how this value depends on data characteristics. In this paper, we derive the first analytic expressions for DShapley for the canonical problems of linear regression, binary classification, and non-parametric density estimation. These analytic forms provide new algorithms to estimate DShapley that are several orders of magnitude faster than previous state-of-the-art methods. Furthermore, our formulas are directly interpretable and provide quantitative insights into how the value varies for different types of data. We demonstrate the practical efficacy of our approach on multiple real and synthetic datasets.
Achieving highly reproducible results in graphite-based Li-ion full coin cells

Jiangtao Hu is currently a postdoctoral research associate at Battery Materials & Systems Group at Pacific Northwest National Laboratory (PNNL). He obtained his PhD degree from Peking University, China in 2018. His research interests mainly lie in fundamental research of structure chemistry, exploring functional materials for energy storage and conversion applications. Bingbin Wu is currently a scientist at Battery Materials & Systems Group at PNNL. He received his PhD in physical chemistry from Wuhan University, China in 2013. Prior to joining PNNL, he was a senior engineer at Amperex Technology Limited where he developed high-energy-density rechargeable Li metal batteries for 3 years. His research interest is to develop high-energy-density and safe lithium batteries for energy storage applications from material and cell design point of view. Sujong Chae is currently an assistant professor at Pukyong National University (PKNU), Republic of Korea. He received his PhD from the School of Energy and Chemical Engineering at Ulsan National Institute of Science and Technology (UNIST), Republic of Korea under the supervision of Professor Jaephil Cho. Then, he carried out his research as a postdoctoral research associate at PNNL. His research interests include the practical development of Si anodes for high-energy lithium-ion batteries. Joshua Lochala is currently a postdoctoral research associate at Battery Materials & Systems Group at PNNL. He received his PhD from the University of Arkansas under the supervision of Dr. Jie Xiao. His research focuses on understanding fundamentals of Li metal protection and its surface properties. He currently works on applying Li metal in high-energy pouch cells at PNNL. Yujing Bi is currently a postdoctorate research associate at Battery Materials & Systems Group at PNNL. He earned his PhD from University of Chinese Academy of Sciences in 2017 after completing his PhD research in Ningbo Institute of Materials Technology & Engineering and University of Western Ontario. Before joining PNNL, he worked as postdoctoral researcher at Utah State University to develop electrolyte and materials for multivalent ion batteries. His present research is devoted to fundamental study of battery material science and develop the battery material technologies. Jie Xiao is currently a Laboratory Fellow and Technical Group Manager of Battery Materials & System Group at PNNL. Dr. Xiao obtained her PhD in Materials Chemistry from State University of New York, Binghamton. Her research interest spans from materials synthesis, electrochemical kinetics, to battery prototyping and manufacturing for electrochemical energy storage. She has published more than 100 peer-reviewed papers, 2 book chapters, and holds 17 US patents in the area of energy storage research area. Dr. Xiao has been named top 1% Clarivate Analytics Highly Cited Researcher since 2017.
Toward a Race-Conscious Critique of Mental Health-Related Exclusionary Immigration Laws

This Article employs the emergent analytical framework of Dis/ability Critical Race Theory (DisCrit) to offer a race-conscious critique of a set of immigration laws that have been left out of the story of race-based immigrant exclusion in the United States—namely, the laws that exclude immigrants based on mental health-related grounds. By centering the influence of the white supremacist, racist and ableist ideologies of the eugenics movement in shaping mental health-related exclusionary immigration laws, this Article locates the roots of these restrictive laws in the desire to protect the purity and homogeneity of the white Anglo Saxon race against the threat of racially inferior, undesirable, and unassimilable immigrants. Moreover, by using a DisCrit framework to critique today’s mental health-related exclusionary law, INA § 212(a)(1)(A)(iii), this Article reveals how this law carries forward the white supremacist, racist, and ableist ideologies of eugenics into the present in order to shape ideas of citizenship and belonging. The ultimate goal of the Article is to broaden the conceptualization of race-based immigrant exclusion to encompass mental health-related immigrant exclusion, while demonstrating the utility of DisCrit as an exploratory analytical tool to examine the intersections of race and disability within immigration law.
Finite-amplitude RF heating rates for magnetized electrons in neutral plasma

A theoretical model is developed and evaluated using a Vlasov–Poisson treatment to calculate radio frequency (RF) electric field heating rates for magnetized electrons in neutral plasma when the magnetic and electric field directions are colinear and when the RF is of sufficiently high frequency. This calculation reduces to the theory for magnetized longitudinal AC conductivity introduced by Oberman and Shure [Phys. Fluids 6, 834–838 (1963)] in the low-amplitude limit when the electron oscillation velocity is much less than the thermal velocity. For electron coupling strengths Γ = 0.15–0.015 and RF fields accessible to ultracold neutral plasma experiments, the model predicts mild variations in heating rate of order unity across magnetization strengths spanning orders of magnitude. The predicted effect of including a Bhatnagar-Gross-Krook-type collisional relaxation term in the Vlasov equation reduces the heating rate by 5% or less across magnetizations.
Supply of immigrant entrepreneurs and native entrepreneurship

Using nationally representative data from the United States, the author estimates the causal impact of immigrant entrepreneurship on entrepreneurial propensities of natives. The author draws data from the Annual Social and Economic Supplement of the Current Population Survey and uses within-state variation in supply of immigrant entrepreneurs for identification. To address concerns of endogeneity in the supply of immigrant entrepreneurs, the author takes advantage of a quasi-experiment provided by the State Children's Health Insurance Program. While the Ordinary Least Squares estimates indicate a positive effect, the Two Stage Least Squares estimates suggest that, on average, there is no significant effect of immigrant entrepreneurs on native entrepreneurship. Moreover, there is no net effect on subgroups of natives separated by skill level. There is also some evidence that immigrant entrepreneurs may “crowd-in” Blacks into certain types of self-employment. These results are in contrast to the significant negative impact suggested by the previous literature.