cssi/SciSciGPT-SciSciNet huggingface dataset:
The Proportionality Principle in Operation: Methodological Limitations of Empirical Research and the Need for Transparency

The principle of proportionality, notoriously obscure in application and subjective in interpretation, has been enforced so rarely as to call into question its potency as a meaningful international legal standard. Nonetheless, international criminal tribunals, academics, and the ICRC's monumental study on customary international humanitarian law all confidently proclaim the principle as embedded in the customary international law applicable to both international and non-international armed conflicts. To assess whether these claims are accurate, and to flesh out how states interpret the principle in practice, the author and a colleague have undertaken a long-term, multinational empirical study of state practice in interpreting and enforcing the proportionality principle. This article discusses the methodological options available and explains the one chosen for the proportionality study. The limitations of the study, in spite of its deliberate methodology, suggest that the debilities of the proportionality principle may not be conceptual as much as a byproduct of unnecessary military secrecy. This article concludes that greater transparency in state compliance with the rule of discrimination and the principle of proportionality would, at least, facilitate an understanding of how the hitherto obscure principle operates in practice and, at best, could create systemic effects that would decrease the dangers to civilians in armed conflicts.
Who is citing whom: Citation network analysis among HRD publications from 1990 to 2007

A citation network analysis among four journals in human resource development (HRD) was conducted to discover the major themes of published articles in HRD. A total of 1,410 articles from 1990 to 2007 were coded. Main path analysis, influence analysis, and reduced network analysis were conducted for citation network analysis. The key findings are 1. The HRD citation network is characterized as high cohesiveness locally and low separation globally. 2. HRD texts tend to gather around texts dealing with three significant topics. 3. A reduced citation network generated based on cliques is divided into four blocks. 4. A geographical position of a text in the citation network is highly associated with the topics (theory building or training transfer) and with the nature of the study (foundational or applied). Implications of the current study and suggestions for future study based on the limitations of the study are addressed.
Does anti-bribery enforcement deter foreign investment?

AbstractThis article presents the first empirical evidence that bilateral fixed capital flows fall in response to anti-bribery enforcement actions. We hand-collect data on individual enforcement actions initiated by the US Department of Justice (DOJ) and show that anti-bribery enforcement in a country is followed by a 40% reduction in foreign fixed capital investments made by US companies in that country.
The role of price spillovers in the American housing boom

Abstract One of the striking features of the last U.S. housing boom was the heterogeneity in the timing of its onset across local markets. In this paper, we exploit this heterogeneity to estimate the extent to which the boom was spread via spatial spillovers from one market to another. Our analysis focuses on spillovers that occur around the time that a local market enters its boom, which we identify using sharp structural breaks in house price growth rates. On the extensive margin, there is evidence that the likelihood of a market booming increases substantially if nearby neighbors boom. On the intensive margin, we also find statistically significant but economically modest effects of the size of a neighbor's boom on subsequent price growth in nearby markets. These affects appear to be unrelated to local market fundamentals, suggesting a potential role for non-rational factors.
The (Un?)Constitutionality of Compelling Non-Immunized Testimony in Deceptive Trade Practices Investigations Conducted By the Attorney General of the State of Arkansas

The Attorney General of the State of Arkansas has the statutory authority to investigate allegations of violations of Arkansas's prohibition on deceptive trade practices. Under this authority, the Attorney General can conduct investigations and file civil enforcement lawsuits. In conducting an investigation, the Attorney General can compel the target of the investigation to produce documents and give a deposition. A violation of Arkansas's prohibition on deceptive trade practices is a civil offense and a crime. Arkansas's' Attorney General, however, does not have the authority to prosecute criminal cases, nor can that office offer a person immunity from a criminal prosecution. Thus, the Attorney General can compel the target of a deceptive trade practices act investigation to produce testimonial evidence that can be used against that target in later criminal prosecution. Because a violation of Arkansas's ban on deceptive trade practices is a criminal offense, and because the Attorney General lacks the authority to grant a person immunity from a criminal prosecution, the Attorney General's authority to compel the target of a deceptive trade practices investigation to produce non-immunized testimonial evidence violates the Fifth Amendment privilege against self-incrimination. This paper explains why that is so, and offers recommendations on how the Arkansas General Assembly can cure the Fifth Amendment problem without adversely impacting the Attorney General's authority to investigate and put an end to deceptive trade practices.
Using Big Data Analytics in Information Technology (IT) Service Delivery

This paper provides some understandings on what big data analytics are, how they work, some of their applications and how big data analytics can improve the IT service delivery in typical IT organization or IT outsourcing service provider's environment. Both discussion and conclusion are also included. The applications of big data analytics include: recommendation, clustering, classification and frequent pattern matching. Examples for the application of big data analytics are categorized into: a) IT staffing and resourcing, b) IT service level and problem management, and c) IT governance and risk management. Some challenges of adopting big data analytics are also discussed which include: a) Big data analytics are not for everyone, b) Shortage of big data analytical skillset, c) Ethical consideration, and d) Careful planning on what big data to collect.
A network efficiency measure with application to critical infrastructure networks

In this paper, we demonstrate how a new network performance/efficiency measure, which captures demands, flows, costs, and behavior on networks, can be used to assess the importance of network components and their rankings. We provide new results regarding the measure, which we refer to as the Nagurney---Qiang measure, or, simply, the N---Q measure, and a previously proposed one, which did not explicitly consider demands and flows. We apply both measures to such critical infrastructure networks as transportation networks and the Internet and further explore the new measure through an application to an electric power generation and distribution network in the form of a supply chain. The Nagurney and Qiang network performance/efficiency measure that captures flows and behavior can identify which network components, that is, nodes and links, have the greatest impact in terms of their removal and, hence, are important from both vulnerability as well as security standpoints.
A CURE FOR DISCRIMINATION? AFFIRMATIVE ACTION AND THE CASE OF CALIFORNIA'S PROPOSITION 209

Proposition 209, enacted in California in 1996 and made effective the following year, ended state affirmative action programs not only in education, but also for public employment and government contracting. This paper uses CPS data and triple difference techniques to take advantage of the natural experiment presented by this change in state law to gauge the labor market impacts of ending affirmative action programs. Employment among women and minorities dropped sharply, a change that was nearly completely explained by a decline in participation rather than by increases in unemployment. This decline suggests that either affirmative action programs in California had been inefficient or that they failed to create lasting change in prejudicial attitudes.
Deviations from Norms and Informed Trading

Investment managers are subject to personal and institutional norms that can constrain their investment choices. We conjecture that norm-constrained investors deviate from such norms only when they have compelling information, and we predict that deviating investments earn relatively high abnormal returns ex post. Consistent with our conjecture, we find that institutions averse to holding lottery-like stocks or sin stocks earn relatively high abnormal returns when they choose to hold such stocks. We find similar but weaker results for deviations from broader style categories. Overall, our evidence indicates that deviations from established institutional or social norms signal informed investing.
Differential Rewards to, and Contributions of, Education in Urban China’s Segmented Labor Markets

Abstract. Using worker data from a 1999–2000 urban enterprise survey, we examine the effects of education on the current earnings of continuously employed urban workers, migrants and laid off but subsequently re-employed workers. We also decompose the earnings differentials between each of these groups of workers and then assess the contribution of education to explanations of the differentials. The empirical results demonstrate that returns to education increase with marketization and competition in the workplace. We also find educational attainment to be an important explanator of the earnings differentials between institutionally differentiated groups of workers in China's urban labor markets.
The Home Court Advantage in International Corporate Litigation

Abstract Using a comprehensive sample of 2,361 public U.S. corporate defendants and 715 public foreign corporate defendants in U.S. federal courts in the period 1995–2000, we find that the market reaction at the announcement of a U.S. federal lawsuit is less negative for U.S. corporate defendants than for foreign corporate defendants. We find that this market reaction is rational; U.S. firms are less likely to lose than are foreign firms when we control for year, industry, type of litigation, size, and profitability. This finding may still reflect a sample selection bias. We control for this bias, and the results remain unchanged. We thus cannot rule out that U.S. firms have a home court advantage in U.S. federal courts.
THE HETEROGENEITY OF RIGHTS

What is the implication for the validity of governmental rules of the conclusion that the rule interferes with a constitutional right? This question has implications for two important doctrinal puzzles. The first is the question when, if ever, a litigant has a constitutional right to an exemption from a generally valid rule of law. Many constitutional rights are rule-dependent in the sense that they protect actors against certain kinds of governmental rules rather than shielding acts against governmental interference. This Article denies the claim by scholars and judges that this rule-dependence reflects a deep truth about the nature of constitutional rights. For example, it would be perfectly consistent to treat free exercise of religion as act-shielding while treating freedom of speech as rule-dependent, or vice-versa. Although a certain conception of the rule of law may lead judges to favor rule-dependence generally, the weight to be given to rule-of-law values, and the weight of countervailing considerations, will vary from context to context. The second doctrinal puzzle involving the relation between rights and rules involves the question of when the courts will entertain a challenge to a statute or other legal rule on its face as opposed to as applied to some particular set of facts. This Article argues that knowing whether a given right is understood as a right against rules or conduct-shielding is not a sufficient basis for knowing whether, and under what circumstances, a court should strike down a rule infringing that right. The key to these questions is severability. A facial challenge should only succeed if there are constitutional, statutory, or pragmatic grounds why a court may not presume the severability of the challenged law's valid and invalid applications. These grounds will be present to greater or lesser degrees depending upon the nature of the right and the nature of the rule infringing the right. Thus, rights are profoundly heterogenous.
Screening Out Innovation:The Merits of Meritless Litigation

Courts and legislatures often conflate merit-less and frivolous cases when balancing the desire to keep courthouse doors open to novel or unlikely claims against the concern that entertaining ultimately unsuccessful litigation will prove too costly for courts and defendants. Recently, significant procedural and substantive barriers to civil litigation have been informed by judicial and legislative assumptions about the costs of entertaining merit-less and frivolous litigation. The prevailing wisdom is that eliminating merit-less and frivolous claims as early in a case’s trajectory as possible will focus scarce resources on the truly meritorious cases, thereby ensuring that available remedies are properly distributed to deserving plaintiffs.Frivolous and merit-less litigation are not the same, however. Frivolous claims are easier to identify at the outset of litigation because they rest on unrecognizable legal theories or fantastical factual allegations. More importantly, merit-less litigation has a distinct and identifiable value that is obscured by conflating merit-less claims with frivolous ones. Unlike frivolous litigation, merit-less litigation can bring to light facts that may lead to systematic reform (even where no legal cause of action lies), lead to legal innovation by announcing new interpretations of common law and statutory and constitutional texts, and pave the way for future changes in the law. Recognizing the value of merit-less litigation and distinguishing merit-less from frivolous cases therefore raises questions about the recent barriers that have been imposed to civil litigation. Taking the value of merit-less litigation into account is essential if we are to strike the correct balance between the costs and benefits of keeping courthouse doors open.
Dispersing Authority or Deepening Divisions? Decentralization and Ethnoregional Party Success

Political scientists have fiercely debated the impact of decentralization on ethnic conflict; some see it as a panacea, while others contend that it sows the seeds of its own failure by stimulating ethnic divisions via ethnoregional parties. Using multiple methods—historical analysis, quantitative case studies, and multivariate models of the share of votes won by ethnoregional parties in 71 democracies—this article demonstrates that ethnoregional parties derive no benefit from decentralization in nonethnically decentralized countries. Even in ethnically decentralized countries, much ethnoregional party success is explained by the continuation of parties that originally pressed for decentralization. Any impact of decentralization on ethnoregional parties can be minimized through the careful construction of institutions to enhance regional autonomy but not statewide influence. Consequently, institutional designers should retain decentralization as an option when crafting political institutions even in count...
DNA Rules: Legal and Conceptual Implications of Biological "Lock-Out" Systems

Recent advances in genetic engineering now allow biological inventions to be programmed in a fashion resembling the restrictive programming of digital media. These biological "lock-out" systems restrict unauthorized use of genetically engineered seeds in much the same way that digital rights management (DRM) systems restrict the use of digital media. Indeed, these new genetic use restriction technologies, known as "GURTs," raise many of the same policy issues that have been identified with DRM. In both cases, the substitution of technological protection for legal protection allows private parties to displace the public policy balance of ownership and control that is inherent in intellectual property law. The proliferation of restrictive technologies such as DRM and GURTs poses a challenge not only to the traditional balance of control over intellectual property, but also to our understanding of legal doctrines related to ownership and control. In particular, the ability to embed contractual terms in restrictive technologies requires a re-examination of the concepts of disclosure and consent in licensing transactions involving such technologies, as well as a reconsideration of commonly employed notions of property and contract. As restrictive technologies blur the distinctions between property, contract, and physical products, these categories may be redefined in light of the interplay between law and the values that restrictive technologies embed in the design of the physical products.
FOOD INGLORIOUS FOOD: FOOD SAFETY, FOOD LIBEL AND FREE SPEECH

Recently, the movie Food, Inc. exposed issues about the food production industry in the United States. That Oscar-nominated documentary included a scene in which a mother, whose child had died from food-borne illness, explained that she could not criticize the food industry without risk of being sued. The risk to which she alluded stems from special legislation against criticism that agriculture and food production enjoy in 13 U.S. states. In the late 20 century, Oprah Winfrey successfully defended one such case under the Texas food libel law based on a show she aired on cattle management. The other states with food libel laws are Alabama, Arizona, Colorado, Florida, Georgia, Idaho, Louisiana, Mississippi, North Dakota, Ohio, Oklahoma and South Dakota. Of these, only Colorado criminalizes food disparagement. The rest establish civil liability and are the focus of this analysis. At the same time the foregoing states are protecting agri-business from criticism, the 21 century has seen a significant increase in health concerns related to food. According to the U.S. Centers for Disease Control and Prevention, 48 million people in the United States get sick, 128,000 are hospitalized, and 3,000 die each year from food-borne diseases. In response to these concerns, the United States adopted a new federal food safety law in January, 2011. Among other things, the law includes whistleblower protection for employees in food production who complain about food safety issues. These new whistleblower protections could directly contravene provisions of state food libel laws that stifle such complaints. Potentially, the new federal law reflects a national public policy about food safety and debate that state food libel laws contradict. This paper analyzes the impact of food disparagement statutes in the United States. First, the paper examines the scope of liability under the twelve civil food libel laws. Further, the analysis considers the reach of the laws to determine what constitutes a violation of the law ―within‖ each relevant state with a food libel statute. This analysis considers whether health and safety statements published in states without food libel laws can become actionable in any state with a food libel law. If so, the effect could be to elevate the laws of twelve states to national food debate policy. Next, the paper discusses the new federal food safety law. In particular, this analysis discusses how whistleblower protections in new federal food safety law affect the enforceability of state food disparagement laws. Finally, paper concludes with analysis and recommendations for future research regarding food debate, food safety and the role of state laws.
The Child Citizenship Act and the Family Reunification Act: Valuing the Citizen Child as Well as the Citizen Parent

Leading civil rights advocates today lament the degree to which current immigration law fails to maintain family unity. The recent passage of the Child Citizenship Act of 2000 is a rare bipartisan step in the right direction because it grants automatic citizenship to foreign-born children of U.S. citizens upon receipt of their permanent resident status and finalization of their adoption. Congress now has before it the Family Reunification Act of 2001, which aims to restore certain procedural safeguards relaxed in 1996 to ensure that foreign-born parents are not summarily separated from their children, many of whom may be U.S. citizens. Because it usually takes both children and parents to create a family, my hope is that Congress will look just as favorably upon the seemingly more complex, but actually less extraordinary, measures suggested in the Family Reunification Act as it did with the Child Citizenship Act of 2000. My fear, however, is that despite its promised gains, embedded within the Child Citizenship Act of 2000 are assumptions that will make passage of key parts of the Family Reunification Act difficult if not impossible. One of these assumptions is that criminal adult legal permanent residents (LPRs) are presumptively deportable unless they happen to be a citizen's adopted child.
Stochastic Comparative Statics in Markov Decision Processes

In multiperiod stochastic optimization problems, the future optimal decision is a random variable whose distribution depends on the parameters of the optimization problem. I analyze how the expecte...
Two distinct trophectoderm lineage stem cells from human pluripotent stem cells.

The trophectoderm layer of the blastocyst-stage embryo is the precursor for all trophoblast cells in the placenta. Human trophoblast stem (TS) cells have emerged as an attractive tool for studies on early trophoblast development. However, the use of TS cell models is constrained by the limited genetic diversity of existing TS cell lines and restrictions on using human fetal tissue or embryos needed to generate additional lines. Here we report the derivation of two distinct stem cell types of the trophectoderm lineage from human pluripotent stem cells. Analogous to villous cytotrophoblasts in vivo, the first is a CDX2- stem cell comparable with placenta-derived TS cells—they both exhibit identical expression of key markers, are maintained in culture and differentiate under similar conditions, and share high transcriptome similarity. The second is a CDX2+ stem cell with distinct cell culture requirements, and differences in gene expression and differentiation, relative to CDX2- stem cells. Derivation of TS cells from pluripotent stem cells will significantly enable construction of in vitro models for normal and pathological placental development.
A tool to predict coercivity in magnetic materials

Abstract Magnetic coercivity is often viewed to be lower in alloys with negligible (or zero) values of the anisotropy constant. However, this explains little about the dramatic drop in coercivity in FeNi alloys at a non-zero anisotropy value. Here, we develop a theoretical and computational tool to investigate the fundamental interplay between material constants that govern coercivity in bulk magnetic alloys. The two distinguishing features of our coercivity tool are that: (a) we introduce a large localized disturbance, such as a spike-like magnetic domain, that provides a nucleation barrier for magnetization reversal; and (b) we account for magneto-elastic energy—however small—in addition to the anisotropy and magnetostatic energy terms. We apply this coercivity tool to show that the interactions between local instabilities and material constants, such as anisotropy and magnetostriction constants, are key factors that govern magnetic coercivity in bulk alloys. Using our model, we show that coercivity is minimum at the permalloy composition ( Fe 21.5 Ni 78.5 ) at which the alloy’s anisotropy constant is not zero. We systematically vary the values of the anisotropy and magnetostriction constants, around the permalloy composition, and identify new combinations of material constants at which coercivity is small. More broadly, our coercivity tool provides a theoretical framework to potentially discover novel magnetic materials with low coercivity.
Force2Vec: Parallel force-directed graph embedding

A graph embedding algorithm embeds a graph into a low-dimensional space such that the embedding preserves the inherent properties of the graph. While graph embedding is fundamentally related to graph visualization, prior work did not exploit this connection explicitly. We develop Force2Vec that uses force-directed graph layout models in a graph embedding setting with an aim to excel in both machine learning (ML) and visualization tasks. We make Force2Vec highly parallel by mapping its core computations to linear algebra and utilizing multiple levels of parallelism available in modern processors. The resultant algorithm is an order of magnitude faster than existing methods (43× faster than DeepWalk, on average) and can generate embeddings from graphs with billions of edges in a few hours. In comparison to existing methods, Force2Vec is better in graph visualization and performs comparably or better in ML tasks such as link prediction, node classification, and clustering. Source code is available at https://github.com/HipGraph/Force2Vec.
Distributed Motion Control for Multiple Connected Surface Vessels

We propose a scalable cooperative control approach which coordinates a group of rigidly connected autonomous surface vessels to track desired trajectories in a planar water environment as a single floating modular structure. Our approach leverages the implicit information of the structure’s motion for force and torque allocation without explicit communication among the robots. In our system, a leader robot steers the entire group by adjusting its force and torque according to the structure’s deviation from the desired trajectory, while follower robots run distributed consensus-based controllers to match their inputs to amplify the leader’s intent using only onboard sensors as feedback. To cope with the nonlinear system dynamics in the water, the leader robot employs a nonlinear model predictive controller (NMPC), where we experimentally estimated the dynamics model of the floating modular structure in order to achieve superior performance for leader-following control. Our method has a wide range of potential applications in transporting humans and goods in many of today’s existing waterways. We conducted trajectory and orientation tracking experiments in hardware with three custom-built autonomous modular robotic boats, called Roboat, which are capable of holonomic motions and onboard state estimation. Simulation results with up to 65 robots also prove the scalability of our proposed approach.
Reply to my critics

This paper offers an overview of the central argument of my book, Territorial Sovereignty, and replies to four critics.
Task-based assessment of binned and list-mode SPECT systems.

In SPECT, list-mode (LM) format allows storing data at higher precision compared to binned data. There is significant interest in investigating whether this higher precision translates to improved performance on clinical tasks. Towards this goal, in this study, we quantitatively investigated whether processing data in LM format, and in particular, the energy attribute of the detected photon, provides improved performance on the task of absolute quantification of region-of-interest (ROI) uptake in comparison to processing the data in binned format. We conducted this evaluation study using a DaTscan brain SPECT acquisition protocol, conducted in the context of imaging patients with Parkinson’s disease. This study was conducted with a synthetic phantom. A signal-known exactly/background-known-statistically (SKE/BKS) setup was considered. An ordered-subset expectation-maximization algorithm was used to reconstruct images from data acquired in LM format, including the scatter-window data, and including the energy attribute of each LM event. Using a realistic 2-D SPECT system simulation, quantification tasks were performed on the reconstructed images. The results demonstrated improved quantification performance when LM data was used compared to binning the attributes in all the conducted evaluation studies. Overall, we observed that LM data, including the energy attribute, yielded improved performance on absolute quantification tasks compared to binned data.
Enabling Large Intelligent Surfaces With Compressive Sensing and Deep Learning

Employing large intelligent surfaces (LISs) is a promising solution for improving the coverage and rate of future wireless systems. These surfaces comprise massive numbers of nearly-passive elements that interact with the incident signals, for example by reflecting them, in a smart way that improves the wireless system performance. Prior work focused on the design of the LIS reflection matrices assuming full channel knowledge. Estimating these channels at the LIS, however, is a key challenging problem. With the massive number of LIS elements, channel estimation or reflection beam training will be associated with (i) huge training overhead if all the LIS elements are passive (not connected to a baseband) or with (ii) prohibitive hardware complexity and power consumption if all the elements are connected to the baseband through a fully-digital or hybrid analog/digital architecture. This paper proposes efficient solutions for these problems by leveraging tools from compressive sensing and deep learning. First, a novel LIS architecture based on sparse channel sensors is proposed. In this architecture, all the LIS elements are passive except for a few elements that are active (connected to the baseband). We then develop two solutions that design the LIS reflection matrices with negligible training overhead. In the first approach, we leverage compressive sensing tools to construct the channels at all the LIS elements from the channels seen only at the active elements. In the second approach, we develop a deep-learning based solution where the LIS learns how to interact with the incident signal given the channels at the active elements, which represent the state of the environment and transmitter/receiver locations. We show that the achievable rates of the proposed solutions approach the upper bound, which assumes perfect channel knowledge, with negligible training overhead and with only a few active elements, making them promising for future LIS systems.
A Bayesian Model of Cash Bail Decisions

The use of cash bail as a mechanism for detaining defendants pretrial is an often-criticized system that many have argued violates the presumption of "innocent until proven guilty." Many studies have sought to understand both the long-term effects of cash bail's use and the disparate rate of cash bail assignments along demographic lines (race, gender, etc). However, such work is often susceptible to problems of infra-marginality - that the data we observe can only describe average outcomes, and not the outcomes associated with the marginal decision. In this work, we address this problem by creating a hierarchical Bayesian model of cash bail assignments. Specifically, our approach models cash bail decisions as a probabilistic process whereby judges balance the relative costs of assigning cash bail with the cost of defendants potentially skipping court dates, and where these skip probabilities are estimated based upon features of the individual case. We then use Monte Carlo inference to sample the distribution over these costs for different magistrates and across different races. We fit this model to a data set we have collected of over 50,000 court cases in the Allegheny and Philadelphia counties in Pennsylvania. Our analysis of 50 separate judges shows that they are uniformly more likely to assign cash bail to black defendants than to white defendants, even given identical likelihood of skipping a court appearance. This analysis raises further questions about the equity of the practice of cash bail, irrespective of its underlying legal justification.
Representations of the (-2,3,7)-Pretzel Knot and Orderability of Dehn Surgeries

Abstract We construct a 1-parameter family of SL 2 ( R ) representations of the pretzel knot P ( − 2 , 3 , 7 ) . As a consequence, we conclude that Dehn surgeries on this knot are left-orderable for all rational surgery slopes less than 6. Furthermore, we discuss a family of knots and exhibit similar orderability results for a few other examples.
A Survey of System Architectures and Techniques for FPGA Virtualization

FPGA accelerators are gaining increasing attention in both cloud and edge computing because of their hardware flexibility, high computational throughput, and low power consumption. However, the design flow of FPGAs often requires specific knowledge of the underlying hardware, which hinders the wide adoption of FPGAs by application developers. Therefore, the virtualization of FPGAs becomes extremely important to create a useful abstraction of the hardware suitable for application developers. Such abstraction also enables the sharing of FPGA resources among multiple users and accelerator applications, which is important because, traditionally, FPGAs have been mostly used in single-user, single-embedded-application scenarios. There are many works in the field of FPGA virtualization covering different aspects and targeting different application areas. In this article, we review the system architectures used in the literature for FPGA virtualization. In addition, we identify the primary objectives of FPGA virtualization, based on which we summarize the techniques for realizing FPGA virtualization. This article helps researchers to efficiently learn about FPGA virtualization research by providing a comprehensive review of the existing literature.
Too Much of a Good Thing: Quality-Differentiated Demand and Monopoly Bias:

Previous teaching notes focused on the logic and mechanics of a quality-differentiated linear demand structure. This note takes up the question of potential bias in how markets respond to quality-r...
Gabor-Type Frames for Signal Processing on Graphs

In the past decade, significant progress has been made to generalize classical tools from Fourier analysis to analyze and process signals defined on networks. In this paper, we propose a new framework for constructing Gabor-type frames for signals on graphs. Our approach uses general and flexible families of linear operators acting as translations. Compared to previous work in the literature, our methods yield the sharp bounds for the associated frames, in a broad setting that generalizes several existing constructions. We also examine how Gabor-type frames behave for signals defined on Cayley graphs by exploiting the representation theory of the underlying group. We explore how natural classes of translations can be constructed for Cayley graphs, and how the choice of an eigenbasis can significantly impact the properties of the resulting translation operators and frames on the graph.
Online to Offline: The Impact of Social Media on Offline Sales in the Automobile Industry

This study examines the dynamic relationships between firm-generated content (FGC), user-generated content (UGC), traditional media, and offline light vehicle sales. Data were collected from the of...
The Sound of Many Funds Rebalancing

This paper proposes that portfolio-rebalancing cascades generate noise in financial markets. In particular, we study the rebalancing decisions of exchangetraded funds (ETFs). Stocks are often held by many different ETFs that track a wide variety of benchmarks. We show theoretically that, when many ETFs are involved, small price changes can trigger large rebalancing cascades that wind up affecting unrelated stocks on the opposite side of the market. We then show empirically that, when many ETFs hold a stock, aggregate ETF demand for that stock passes statistical tests for white noise and that aggregate ETF volume predicts total trading volume, liquidity, and insider-trading activity. These results persist when we instrument for aggregate ETF volume with the number of unrelated ETFs in the market—that is, with the number of ETFs that hold neither the target stock nor any stocks held by ETFs that hold the target stock. The number of unrelated ETFs is correlated with the potential for rebalancing cascades but not with characteristics of the target stock, so our results are unlikely to be driven by unobserved stock-level differences. JEL Classification. G02, G12, G14
Reversing the Trend: The Recent Expansion of the Reverse Mortgage Market

Reverse mortgages allow elderly homeowners to consume their housing wealth without having to sell or move out of their homes. However, very few eligible homeowners have used reverse mortgages to achieve consumption smoothing until recently when the reverse mortgage market in the U.S. witnessed substantial growth. This paper examines 1989-2007 loan-level reverse mortgage data and presents a number of findings. First, I show that recent reverse mortgage borrowers are significantly different from earlier borrowers in many respects. Second, I find that borrowers who take the line-ofcredit payment plan, single male borrowers, and borrowers with higher housing values exit their homes sooner than other reverse mortgage borrowers. Third, I combine the reverse mortgage data with county-level housing price data to show that elderly homeowners are more likely to purchase reverse mortgages when the local housing market is at its peak. This finding suggests that the 2000-05 housing market boom may be partially responsible for the rapid growth in the reverse mortgage market. Lastly, I show that the Federal Housing Administration (FHA) mortgage limits, which cap the amount of housing wealth that an eligible homeowner can borrow against, have little effect on the demand for reverse mortgages. This paper is the first to perform such analyses using actual loan-level reverse mortgage data. The findings have important implications to both policy making and the economics of housing and aging.
Crosscap number and epimorphisms of two-bridge knot groups

We consider the relationship between the crosscap number γ of knots and a partial order on the set of all prime knots, which is defined as follows. For two knots K and J, we say K ≥ J if there exis...
Violation of the Onsager relation for quantum oscillations in superconductors

We numerically study the quantum oscillations in superconducting vortex-mixed states with $d$-wave pairing. We show that in the parameter range of an underdoped cuprate superconductor, the commonly held assumption that the period is given by the underlying Fermi-surface area using the Onsager relation becomes invalid. Using this result, we conclude that the interpretation of the recent experimental data on YBCO as a signal of an underlying Fermi surface with four hole pockets created by a $(\ensuremath{\pi},\ensuremath{\pi})$ folding cannot be ruled out.
Increasing power for observational studies of aberrant response: An adaptive approach

In many observational studies, the interest is in the effect of treatment on bad, aberrant outcomes rather than the average outcome. For such settings, the traditional approach is to define a dichotomous outcome indicating aberration from a continuous score and use the Mantel–Haenszel test with matched data. For example, studies of determinants of poor child growth use the World Health Organization’s definition of child stunting being height‐for‐age z‐score ≤ − 2. The traditional approach may lose power because it discards potentially useful information about the severity of aberration. We develop an adaptive approach that makes use of this information and asymptotically dominates the traditional approach. We develop our approach in two parts. First, we develop an aberrant rank approach in matched observational studies and prove a novel design sensitivity formula enabling its asymptotic comparison with the Mantel–Haenszel test under various settings. Second, we develop a new, general adaptive approach, the two‐stage programming method, and use it to adaptively combine the aberrant rank test and the Mantel–Haenszel test. We apply our approach to a study of the effect of teenage pregnancy on stunting.
Pre-Hausdorff spaces

This paper introduces three separation conditions for topological spaces, called T_{0,1}, T_{0,2} ("pre-Hausdorff"), and T_{1,2}. These conditions generalize the classical T_(1) and T_(2) separation axioms, and they have advantages over them topologically which we discuss. We establish several different characterizations of pre-Hausdorff spaces, and a characterization of Hausdorff spaces in terms of pre-Hausdorff. We also discuss some classical Theorems of general topology which can or cannot be generalized by replacing the Hausdorff condition by pre-Hausdorff.
New perspective on chiral exceptional points with application to discrete photonics

Chiral exceptional points (CEPs) have been shown to emerge in traveling wave resonators via asymmetric back scattering from two or more nano-scatterers. Here, we provide a new perspective on the formation of CEPs based on the coupled oscillator model. Our approach provides an intuitive understanding for the modal coalescence that signals the emergence of CEPs and emphasizes the role played by dissipation throughout this process. In doing so, our model also unveils an otherwise unexplored connection between CEPs and other types of exceptional points associated with parity-time symmetric photonic arrangements. In addition, our model also explains qualitative results observed in recent experimental work involving CEPs. Importantly, the tight-binding nature of our approach allows us to extend the notion of CEP to discrete photonics setups that consist of coupled resonator and waveguide arrays, thus opening new avenues for exploring the exotic features of CEPs in conjunction with other interesting physical effects such as nonlinearities and topological protections.
A novel reconstruction technique for two-dimensional Bragg scatter imaging

Here we introduce a new reconstruction technique for two-dimensional Bragg Scattering Tomography (BST), based on the Radon transform models of (Webber, James W., and Eric L. Miller. "Bragg scattering tomography." arXiv preprint arXiv:2004.10961, 2020). Our method uses a combination of ideas from multibang control and microlocal analysis to construct an objective function which can regularize the BST artefacts, e.g., the boundary artefacts due to sharp cutoff in sinogram space, as observed in (Webber, James W., and Eric Todd Quinto. "Microlocal analysis of generalized Radon transforms from scattering tomography." arXiv preprint arXiv:2007.00208, 2020), and errors due to attenuation and Compton noise. We then go on to test our algorithm in a variety of Monte Carlo (MC) simulated examples of practical interest in airport baggage screening and threat detection.
Three-Axis Magnetometer Calibration Using Total Least Squares

In this paper attitude-independent three-axis magnetometer (TAM) sensor calibration algorithms are presented from a total least squares approach. One algorithm estimates biases only, whereas the ot...
Optimally selecting the top k values from X + Y with layer-ordered heaps.

Selection and sorting the Cartesian sum, X + Y, are classic and important problems. Here, a new algorithm is presented, which generates the top k values of the form X i + Y j . The algorithm relies on layer-ordered heaps, partial orderings of exponentially sized layers. The algorithm relies only on median-of-medians and is simple to implement. Furthermore, it uses data structures contiguous in memory, cache efficient, and fast in practice. The presented algorithm is demonstrated to be theoretically optimal.
With linear pricing, can profit-maximizing monopoly output be socially efficient?

We question the prevailing wisdom that a profit-maximizing monopolist using linear pricing cannot produce socially efficient output. We show that when market demand function exhibits a flat portion, the prevailing wisdom may not be true. Such a flat portion in demand is consistent with weakly convex preferences, and many general demand functions such as any polynomials of degree three and higher. Thus, our analysis demonstrates that the output distortion resulting from linear pricing by a profit-maximizing monopolist is demand specific. In general, neither monopoly per se nor linear pricing is the main reason for social inefficiency.
Examining the Presence of Gender Bias in Customer Reviews Using Word Embedding

Humans have entered the age of algorithms. Each minute, algorithms shape countless preferences from suggesting a product to a potential life partner. In the marketplace, algorithms are trained to learn consumer preferences from customer reviews because user-generated reviews are considered the voice of customers and a valuable source of information to firms. Insights, minded from reviews, play an indispensable role in several business activities ranging from product recommen-dations, targeted advertising, promotions, segmentation, etc. In this research, we question whether reviews might hold stereotypic gender bias that algorithms learn and propagate. Utilizing data from millions of observations and a word embedding approach, GloVe, we show that algorithms designed to learn from human language output, also learn gender bias. We also examine why such biases occur: whether the bias is caused because of a negative bias against females or a positive bias for males. We examine the impact of gender bias in reviews on choice and conclude with policy implications for female consumers, especially when they are unaware of the bias, and the ethical implications for the firms.
Some open problems in the theory of composites.

A selection of open problems in the theory of composites is presented. Particular attention is drawn to the question of whether two-dimensional, two-phase composites with general geometries have th...
EventPlus: A Temporal Event Understanding Pipeline.

We present EventPlus, a temporal event understanding pipeline that integrates various state-of-the-art event understanding components including event trigger and type detection, event argument detection, event duration and temporal relation extraction. Event information, especially event temporal knowledge, is a type of common sense knowledge that helps people understand how stories evolve and provides predictive hints for future events. EventPlus as the first comprehensive temporal event understanding pipeline provides a convenient tool for users to quickly obtain annotations about events and their temporal information for any user-provided document. Furthermore, we show EventPlus can be easily adapted to other domains (e.g., biomedical domain). We make EventPlus publicly available to facilitate event-related information extraction and downstream applications.