cssi/SciSciGPT-SciSciNet huggingface dataset:
A stochastic multidimensional scaling procedure for the empirical determination of convex indifference curves for preference/choice analysis

The vast majority of existing multidimensional scaling (MDS) procedures devised for the analysis of paired comparison preference/choice judgments are typically based on either scalar product (i.e., vector) or unfolding (i.e., ideal-point) models. Such methods tend to ignore many of the essential components of microeconomic theory including convex indifference curves, constrained utility maximization, demand functions, et cetera. This paper presents a new stochastic MDS procedure called MICROSCALE that attempts to operationalize many of these traditional microeconomic concepts. First, we briefly review several existing MDS models that operate on paired comparisons data, noting the particular nature of the utility functions implied by each class of models. These utility assumptions are then directly contrasted to those of microeconomic theory. The new maximum likelihood based procedure, MICROSCALE, is presented, as well as the technical details of the estimation procedure. The results of a Monte Carlo analysis investigating the performance of the algorithm as a number of model, data, and error factors are experimentally manipulated are provided. Finally, an illustration in consumer psychology concerning a convenience sample of thirty consumers providing paired comparisons judgments for some fourteen brands of over-the-counter analgesics is discussed.
Copyright for Blockheads: An Empirical Study of Market Incentive and Intrinsic Motivation

Copyright law is widely perceived as the means to promote social welfare by providing a necessary incentive for intellectual creation. However, there has been little clarity in copyright literature on how artists actually respond to copyright incentives: What factors motivate artists to create works? How do artists perceive the usefulness of copyright protection? Would artists continue their artistic careers in a world without copyright law? This Article contains a systematic study regarding copyright incentives, based on industrial statistics and extensive interviews from the music industry in China—a virtually copyright-free environment featuring one of the highest piracy rates in the world, which has caused a dramatic transformation of the music business. The empirical research indicates three seemingly paradoxical phenomena: (1) while 17.9% of all the musicians in the sample referred to economic benefits as at least part of their motivations for music creation, 97.4% specifically recognized money as being important and helpful for music creation; (2) while 56.4% alleged that copyright piracy did not affect their creative motivations, 72% agreed that copyright piracy does affect music creation and (3) while 53.8% explicitly admitted that they had little awareness or knowledge of copyright, 92.3% indicated that the current level of copyright protection is insufficient and 71.8% suggested that copyright law should provide strong incentives for music creation. The empirical evidence itself provides compelling explanations for such paradoxes: Even though musicians seem to primarily create music for music’s sake, copyright law could still supply powerful incentives for music production in a way that not only caters to market demand, but also allows for broader artistic freedom. Copyright piracy that does not necessarily affect musicians’ intrinsic motivations could nevertheless affect music creation in terms of the time spent on music creation, the volume of investment in music creation and, ultimately, the quality of music creation. Most importantly, copyright incentives do not function as a reward that musicians consciously bargain for and chase after, but as a mechanism that preserves market conditions for gifted musicians to prosper, including a decent standard of living, sufficient income to cover production costs and maximum artistic autonomy during the creative process.
Star clusters under stress: why small systems cannot dynamically relax

Utilizing a series of N-body simulations, we argue that gravitationally bound stellar clusters of modest population evolve very differently from the picture presented by classical dynamical relaxation theory. The system’s most massive stars rapidly sink towards the centre and form binary systems. These binaries efficiently heat the cluster, reversing any incipient core contraction and driving a subsequent phase of global expansion. Most previous theoretical studies demonstrating deep and persistent dynamical relaxation have either conflated the process with mass segregation, ignored three-body interactions, or else adopted the artificial assumption that all cluster members are single stars of identical mass. In such a uniform-mass cluster, binary formation is greatly delayed, as we confirm here both numerically and analytically. The relative duration of core contraction and global expansion is effected by stellar evolution, which causes the most massive stars to die out before they form binaries. In clusters of higher N, the epoch of dynamical relaxation lasts for progressively longer periods. By extrapolating our results to much larger populations, we can understand, at least qualitatively, why some globular clusters reach the point of true core collapse.
Diffusion of Emissions Abating Technology

The environmental Kuznets curve (EKC) has been extensively criticized on econometric and theoretical grounds. Recent econometric results and case studies show that national emissions of important pollutants are monotonic in income but changes in technology can lead over time to reductions in pollution - a lowering of the EKC - and that pollution reducing innovations and standards may be adopted with relatively short time lags in some developing countries. This study combines the recent literature on measuring environmental efficiency and technological change using production frontier methods with the use of the Kalman filter - a time series method for signal extraction - to model the state of abatement technology in a panel of countries over time. The EKC is reformulated as the best practice technology frontier - countries' position relative to the frontier reflects the degree to which they have adopted best practice. The results are used to determine whether countries are converging to best practice over time and how many years it will take each country to achieve current best practice. The model is applied to sulfur dioxide emissions from sixteen mainly developed countries.
THE JOINT CROSS SECTION OF STOCKS AND OPTIONS

Stocks with large increases in call (put) implied volatilities over the previous month tend to have high (low) future returns. Sorting stocks ranked into decile portfolios by past call implied volatilities produces spreads in average returns of approximately 1% per month, and the return differences persist up to six months. The cross section of stock returns also predicts option implied volatilities, with stocks with high past returns tending to have call and put option contracts that exhibit increases in implied volatility over the next month, but with decreasing realized volatility. These predictability patterns are consistent with rational models of informed trading.
Third-Party Litigation Funding - A Signaling Model

Elwin Francis settled his personal injury case for $150,000 and walked away with $111 from the settlement. Yes, the lawyers got their one-third, but this is not a story about attorney malpractice. Mr. Francis’s limited recovery stems from his involvement with the new kid in town, third-party litigation funders. Several years before the case settled, Mr. Francis borrowed money from LawCash and Lawbuck$, two litigation funding companies, via non-recourse loans. The nature of the loans meant that he only had to repay them if his case was successful. The catch was the extremely high interest rate, much higher than rates charged by credit card companies. All told Mr. Francis borrowed $27,000, but with the high interest rates by the time the case had settled that amount due had swelled to $96,000. Out of the $150,000 settlement, LawCash and Lawbuck$ received a profit $69,000 in interest that amounted to 46 percent of the settlement, the repayment of the principle of the loans represented another 18 percent, the attorney fees and expenses took a little more than a third, and the plaintiff was left nothing except for the money that had been advanced to him by the funding companies. While this situation sounds like an extreme example, the loan arrangement is not unique, and is part of a larger trend of third party litigation funding that has been sweeping across America in recent years.
Early Decision and College Performance.

Abstract This paper examines the relationship between admission status and college performance. In particular, we analyze admissions data from Hamilton College and find that students who applied through the Early Decision Plan II program have significantly lower GPAs and are less likely to receive departmental honors, fellowships, and outside scholarships than those admitted through the regular decision process. However, the results for Early Decision Plan I students are less consistent. These students have lower outcomes for some measures of academic achievement, but not others, than regular decision students.
Using and Designing Platforms for In Vivo Educational Experiments

In contrast to typical laboratory experiments, the everyday use of online educational resources by large populations and the prevalence of software infrastructure for A/B testing leads us to consider how platforms can embed in vivo experiments that do not merely support research, but ensure practical improvements to their educational components. Examples are presented of randomized experimental comparisons conducted by subsets of the authors in three widely used online educational platforms -- Khan Academy, edX, and ASSISTments. We suggest design principles for platform technology to support randomized experiments that lead to practical improvements -- enabling Iterative Improvement and Collaborative Work -- and explain the benefit of their implementation by WPI co-authors in the ASSISTments platform.
Entertainment Law - The Specter of Malpractice Claims and Disciplinary Actions

There is significant risk today that lawyers will become the target of a disciplinary or legal malpractice action, especially given the complexity of the law and advances in technology that reduce the amount of time that lawyers have to reflect about client matters. This risk is heightened by the increased competition in the bar to deliver legal services in a cost-effective manner, the sophistication of clients who expect competent, efficient and reasonably priced services, and the litigious nature of consumers. The risk is further exacerbated by the ever-changing methods and rules for electronic communication and the storage of information. The magnitude of the risk is underscored by the prediction that law school graduates will be the subject of three or more claims of legal malpractice before finishing a career. This article examines some good practice standards that minimize the risk that a lawyer will become the target of a legal malpractice or disciplinary action. These standards should also reduce the risk of a lawyer becoming the object of a disqualification or Rule 11 motion. This article discusses these standards in the entertainment law context but they also apply to a variety of practice areas, for example, sports law.
Impact of outsourcing on business-to-business marketing: An agenda for inquiry

Abstract Increasing globalization has made companies focus more on their outsourcing decisions. Moving beyond the tactical companies have begun to incorporate outsourcing as a strategic weapon in their armory. This article expands on this theme by highlighting the need for understanding this key issue from business marketing and sales perspective and pointing to some interesting research issues on the topic. The article also introduces this special issue, briefly discusses the six special issue articles and provides a framework that integrates their contributions to our understanding of strategic outsourcing.
HISTORICAL LEGACY AND INSTITUTIONS ACROSS COUNTRIES

Several recent theories postulate why some countries were able to devise institutions conducive to long-run economic growth whereas others were not. Most of these consider various historical factors or geographic characteristics as important predeterminants. But which of these theories comes closest to the truth? This paper simultaneously considers several competing theories and empirically examines which ones provide the strongest explanations for contemporary institutions. I find that settler mortality rates are strongly associated with contemporary institutions even when controlling for other important historical factors, including ones from theories that do not emphasize geographic characteristics. However, Englebert’s concept of state legitimacy does best at explaining institutional outcomes within sub-Saharan Africa.
Revenge of the Bellheads: How the Netheads lost control of the Internet

Abstract Throughout their short, but volatile lives, Internet Service Providers (ISPs) have avoided having to satisfy traditional telecommunications regulatory requirements. ISPs do not operate as common carriers and do not have to pay access charges and make contributions to universal service funding. Having sponsored development of the Internet, many governments consider regulation anathema, despite the fact that ISPs no longer need incubation and many offer some services functionally equivalent to what regulated telephone companies provide. A dichotomy in regulatory treatment exists between ISPs and telecommunications carriers. A large difference in corporate cultures supports this dichotomy. Telephone company executives (Bellheads) may resent regulation, but they accept their fate and work creatively to exploit anomalies and opportunities to secure a regulation-conferred competitive advantage. Most ISP executives (Netheads) appear to embrace a libertarian attitude, strongly opposing any government involvement. Despite the clash of cultures, the telecommunications and Internet worlds have merged. Such convergence jeopardizes the ability of Netheads to avoid some degree of regulation, particularly when they offer services functionally equivalent to what their Bellhead counterparts offer. This paper will assess the regulatory consequences when telecommunications and Internet services converge in the marketplace and in terms of operating technologies. The paper identifies commercial developments in the Internet to support the view that the Internet has become more hierarchical and more like telecommunications networks. For example, the major Internet backbone providers, commonly referred to as Tier-1 ISPs now require smaller ISPs to pay for access rather than simply grant reciprocal “peering” rights. The paper concludes that ownership of the major Tier-1 ISPs and local facilities by incumbent telecommunications carriers provides the basis for management and control of the Internet. Additional opportunities for leadership results from incumbent Bellheads’ superior skill in working the regulatory process to their advantage. The paper suggests that Bellheads will outmaneuver Netheads particularly when the revenue siphoning effect of Internet-mediated services offsets the revenues generated from ISP leases of telecommunications transmission capacity.
Heads I win, tails you lose: Asymmetric taxes, risk taking, and innovation

Abstract When multinationals face lower tax rates abroad than in the US, transfer pricing strategies generate an asymmetry in the tax rates on a project’s profits and losses. We show that the tax savings from transfer pricing can be expressed as a long position in a call option. We use a model to show that this transfer pricing call option leads a firm to choose riskier and larger projects than it would otherwise. Thus, transfer pricing strategies do not simply reduce a firm’s taxes, they can influence the scale and types of projects undertaken.
THE WORD[] ‘PERSON’ . . . INCLUDES CORPORATIONS”:WHY THE RELIGIOUS FREEDOM RESTORATION ACT PROTECTS BOTH FOR- AND NONPROFIT CORPORATIONS

In recent months, lawsuits challenging the Patient Protection and Affordable Care Act’s (ACA) requirement that providers of health insurance pay for contraceptives and potentially abortifacient drugs have attracted attention from legal commentators, the news media, and even the Supreme Court. Plaintiffs argue that the contraception mandate violates the Religious Freedom Restoration Act (RFRA) by imposing a substantial burden on their religious exercise without meeting strict scrutiny requirements.5 On the merits, one commentator has already gone as far as labeling these cases “open-and-shut violation[s] of [RFRA].” Early circuit court decisions at the preliminary injunction phase foreshadowed a circuit split on the issue, with some siding with the plaintiffs, and others siding with the government.8 Recently, the Tenth Circuit issued a complicated en banc decision in Hobby Lobby Stores, Inc. v. Sebelius, which reversed a lower court decision that denied the company’s request for an injunction. The Tenth Circuit’s decision helps highlight the current debate over whether for-profit corporations can use RFRA to avoid the ACA’s requirements and outlines the general themes of this debate. Although that case was a victory for the plaintiffs, the fractured nature of the decision only underscores the likelihood that this issue will ultimately land on the Supreme Court’s doorstep. And it is not without good reason that the Supreme Court will likely take up this issue in the near future.
Noncooperative game theory for industrial organization : an introduction and overview

Publisher Summary Noncooperative game theory is a way of modelling and analyzing situations in which each player's optimal decisions depend on his beliefs or expectations about the play of his opponents. Game-theoretic methodology has caused deep and wide-reaching changes in the way that practitioners think about key issues in oligopoly theory, much as the idea of rational expectations has revolutionized the study of macroeconomics. This chapter reviews those aspects of the noncooperative game theory that are most commonly used by industrial organization economists and describes the most important applications of the theory. There are two equivalent ways of formulating a game. The first is the extensive form. An extensive form specifies (1) the order of play, (2) the choices available to a player whenever it is his turn to move, (3) the information a player have at each of these turns, (4) the payoffs to each player as a function of the moves selected, and (5) the probability distributions for moves by “Nature.”
Toward a complexity theory of information systems development

Purpose – Existing literature acknowledges information systems development (ISD) to be a complex activity. This complexity is magnified by the continuous changes in user requirements due to changing organizational needs in changing external competitive environments. Research findings show that, if this increasing complexity is not managed appropriately, information systems fail. The paper thus aims to portray the sources of complexity related to ISD and to suggest the use of complexity theory as a frame of reference, analyzing its implications on information system design and development to deal with the emergent nature of IS.Design/methodology/approach – Conceptual analysis and review of relevant literature.Findings – This article provides a conceptual model explaining how top‐down “official” and bottom‐up “emergent” co‐evolutionary adaptations of information systems design with changing user requirements will result in more effective system design and operation. At the heart of this model are seven firs...
The Economics and Regulation of Network Branded Prepaid Cards

General-purpose reloadable prepaid cards have been one of the fastest-growing sectors of the consumer payments marketplace in recent years. Their importance has accelerated as a consequence of new regulations enacted in the wake of the 2008 financial crisis. This increased use of prepaid cards has also increased angst among regulators, especially regarding the number and size of fees on prepaid cards. State and federal regulators as well as Congress are interested in imposing new regulations on prepaid cards. These calls for regulation, however, have proceeded in a largely fact-free environment. This paper describes the current economic and regulatory landscape for prepaid cards. The market appears to be robustly competitive, as recent years have seen declining costs and increasing functionality as well as entry of major players such as American Express and several large banks. Nor is there any evidence that consumers systematically err in the cards that they choose. Absent a demonstrable competitive market failure or systematic consumer abuse, prescriptive regulation of the terms and substance of prepaid cards would likely have unintended consequences that would exceed the benefits to consumers. On the other hand, there are some regulations that might be enacted that could promote competition and consumer welfare in this rapidly evolving market.
The Politics of the Exhibition: Viewing Corporate Museums Through the Paradigmatic Lens of Organizational Memory

This paper explores corporate museums as little–understood sites of organizational memory and proposes that corporate museums, as a form of organizational memory, are used strategically by organizations in the development of the firm’s identity and image. More critically, the authors examine the politics of the exhibition of organizational memory, or what Sturken refers to as ‘organized forgetting’ or ‘strategic forgetting’. The authors propose that organizations, through these museums, choose what is recalled (the politics of remembering) as well as what is not remembered (the politics of forgetting). Four propositions are suggested to guide future research on corporate museums with the purpose of furthering our understanding of these museums and their relationship to the development of organizational identity and image as well as organizational actions – past, present, and future. The paper concludes with implications for the organizational–studies scholar.
Our Non-Originalist Right to Bear Arms

District of Columbia v. Heller was a landmark, if controversial, opinion. Discussion has centered on the merits of its self-described originalist approach. Supporters praise its efforts to return to a more originalist and textualist approach to constitutional questions, whereas critics challenge the accuracy of Heller’s historical claims and criticize its departure from precedent. This Article challenges much of the conventional wisdom about Heller, its use of originalism, and its relationship to nineteenthand twentieth-century case law. This Article argues that, despite much of its rhetoric, Heller actually exemplified popular constitutionalism—not originalism—in the way it approached the most important practical question at issue in the case: determining the content of the right to bear arms. On that question, Heller—and not United States v. Miller—is largely consistent with the way, throughout most of American history, that both state and federal courts have adjudicated cases involving the right to bear arms. In particular, this Article argues that the dominant approach followed by nineteenth-century courts was neither “originalist” nor “textualist” about the right to bear arms. These courts did not look to how James Madison viewed the right in 1789 or how Americans in 1791 commonly understood the Second Amendment. Instead, they attempted to find compromise positions on the scope of the right to bear arms to accommodate a population divided between those believing in the right and those seeking stronger restrictions on weapons. To do this, the nineteenth-century courts shifted their understanding of the purpose of the right to bear arms over time, which, in turn, enabled them to reach conclusions about the content of the right that reflected the contemporaneous popular understanding of the right—and of the right’s limits. In this revisionist account, Miller is the case that represented a break with the courts’ historical approach because it arguably allowed access to common military weapons—an approach that did not readily allow courts to adjust the Second Amendment right to new circumstances as these military weapons became increasingly destructive. These difficulties prompted subsequent lower courts to adopt the “collective rights” interpretation of Miller— an interpretation that was too rigidly restrictive, and therefore, also difficult to adjust to reflect popular understandings. The Article concludes that Heller reflects a new compromise: expanding the individual self-defense rationale while diminishing the Second Amendment’s military objectives. This new compromise recognizes an individual right to have self-defense weapons, while allowing greater
Delegated Investment Decisions and Private Benefits of Control

This paper studies the capital budgeting process in a setting where a manager is privately informed about the profitability of an investment project and enjoys nonpecuniary benefits of control (“empire benefits”). I characterize the optimal required rate of return and show that a delegation scheme with residual income‐based compensation can replicate the benchmark performance achieved under centralization. The main result of the paper is that the optimal capital charge rate for computing residual income always exceeds the required rate of return as a result of empire benefits. This highlights the necessity for future empirical studies on capital budgeting to distinguish between alternative forms of hurdle rates. Contrary to conventional wisdom, I further show that if compensation contracts are derived endogenously, then the shareholders will ultimately benefit from the manager's empire benefits even under asymmetric information.
Bargaining with Hippocrates: managed care and the doctor-patient relationship.

In order to reduce the number of unnecessary, and potentially even harmful, medical interventions, managed care imposes oversight on health care expenses. Oversight includes external controls on physician spending and internal financial incentives intended to bring the self-interest of the individual physician in line with the fiscal goals of the managed care organization. The current legal framework for such incentives presumes that patients can negotiate with physicians and other health care providers for their desired mix of cost savings and professional fidelity, if only the playing field is leveled through appropriate disclosures. This article will focus on the financial incentives provided to physicians by MCOs in order to change physicians' practice methods and patterns, and the conflicts of interest caused by those financial incentives. The article proposes a new way of thinking about regulation of financial incentives - a paradigm of respect for the personhood of patients and their unique position within the health care system, and proposes that the traditional physician-patient relationship be protected by insulating the central features of the doctor-patient relationship from the operations of the health care marketplace.
Union Lawyers and Employment Law

A major challenge facing labor activists and scholars today, given the small percentage of the private sector workers who are union members, is to find a new role for unions in attaining decent working conditions for the vast majority of the American workforce that is not unionized. Many unions have launched major efforts to enforce employment law in nonunion workplaces where statutory violations are rampant. The lower the wages, the more likely that fundamental employment laws, including safety, wage and hour laws, will be violated. Low-wage employees are apt to lack the knowledge and the resources to enforce their rights, and there are too few government inspectors to ensure compliance in workplaces all over the country. The article examines the labor law, constitutional, and ethical implications of this important new union strategy. The National Labor Relations Act (NLRA) has been interpreted to prohibit employers and unions from conferring benefits on employees during the critical period prior to a union certification election. The provision of legal representation (except assistance in filing unfair labor practice charges with the National Labor Relations Board (NLRB)) has been deemed to be an unlawful pre-election benefit. Although the NLRB has insisted that the provision of such services is not an unlawful benefit nor grounds to set aside an election, the D.C. and Sixth Circuit courts of appeals disagreed and set aside elections. Because employers may seek review of any union election in the D.C. Circuit, no union can confidently provide pre-election legal representation. The article also shows that to prohibit unions from providing legal assistance to non-member employees in employment law matters while allowing them to do so for unfair labor practice charges is an unconstitutional content-based restriction on First Amendment activity. In addition, forcing employees to choose between exercising their right to union representation for collective bargaining and their right to union lawyers' representation for employment litigation impermissibly requires employees to sacrifice important First Amendment rights as a condition of obtaining an NLRB-sponsored election. Finally, the article also critiques recent cases holding that union lawyers cannot ethically represent non-union members. The article explores the relevant law on conflicts of interest and shows that unions' new effort to bring employment law litigation is consistent with the highest standards of professional ethics.
Income and health spending: Evidence from oil price shocks

Health expenditures as a share of GDP in the United States have more than tripled over the past half-century. A common conjecture is that this is a consequence of rising income. We investigate this hypothesis by instrumenting for local area income with time series variation in oil prices interacted with local oil reserves. This strategy enables us to capture both partial equilibrium and local general equilibrium effects of income on health expenditures. Our central income elasticity estimate is 0.7, with 1.1 as the upper end of the 95% confidence interval, which suggests that rising income is unlikely to be a major driver of the rising health expenditure share of GDP. © 2013 The President and Fellows of Harvard College and the Massachusetts Institute of Technology.
A Mask That Eats into the Face: Images and the Right of Publicity

In their eagerness to reward celebrities for the power of their “images,” and to prevent other people from exploiting those images, courts have allowed the right of publicity to distort the First Amendment. The power of the visual image has allowed courts to create an inconsistent, overly expansive regime that would be easily understood as constitutionally unacceptable were the same rules applied to written words as are applied to drawings and video games. The intersection of a conceptually unbounded right with a category of objects that courts do not handle well has created deep inconsistencies and biases in the treatment of visual and audiovisual media, particularly comics and video games. These problems show up both in First Amendment defenses and in copyright preemption analysis. The possible arguments one might offer for treating images differently are insufficient to justify this disparity. The Article concludes that, absent the distortion produced by images, the right of publicity would properly be understood as sharply limited.
Analog Lagrange Coded Computing

A distributed computing scenario is considered, where the computational power of a set of worker nodes is used to perform a certain computation task over a dataset that is dispersed among the workers. Lagrange coded computing (LCC), proposed by Yu et al. , leverages the well-known Lagrange polynomial to perform polynomial evaluation of the dataset in such a scenario in an efficient parallel fashion while keeping the privacy of data amidst possible collusion of workers. This solution relies on quantizing the data into a finite field, so that Shamir’s secret sharing, as one of its main building blocks, can be employed. Such a solution, however, is not properly scalable with the size of dataset, mainly due to computation overflows. To address such a critical issue, we propose a novel extension of LCC to the analog domain, referred to as analog LCC (ALCC). All the operations in the proposed ALCC protocol are done over the infinite fields of ${ \mathbb R}/ { \mathbb C}$ but for practical implementations floating-point numbers are used. We characterize the privacy of data in ALCC, against any subset of colluding workers up to a certain size, in terms of the distinguishing security (DS) and the mutual information security (MIS) metrics. Also, the accuracy of outcome is characterized in a practical setting assuming operations are performed using floating-point numbers. Consequently, a fundamental trade-off between the accuracy of the outcome of ALCC and its privacy level is observed and is numerically evaluated. Moreover, we implement the proposed scheme to perform matrix-matrix multiplication over a batch of matrices. It is observed that ALCC is superior compared to the state-of-the-art LCC, implemented using fixed-point numbers, assuming both schemes use an equal number of bits to represent data symbols.
Codes for Correcting Localized Deletions

We consider the problem of constructing binary codes for correcting deletions that are localized within certain parts of the codeword that are unknown a priori. The model that we study is when $\delta \leq w$ deletions are localized in a window of size $w$ bits. These $\delta $ deletions do not necessarily occur in consecutive positions, but are restricted to the window of size $w$ . The localized deletions model is a generalization of the bursty model, in which all the deleted bits are consecutive. In this paper, we construct new explicit codes for the localized model, based on the family of Guess & Check codes which was previously introduced by the authors. The codes that we construct can correct, with high probability, $\delta \leq w$ deletions that are localized in a single window of size $w$ , where $w$ grows with the block length. Moreover, these codes are systematic; have low redundancy; and have efficient deterministic encoding and decoding algorithms. We also generalize these codes to deletions that are localized within multiple windows in the codeword.
To update or not to update? Delayed nonparametric bandits with randomized allocation

Delayed rewards problem in contextual bandits has been of interest in various practical settings. We study randomized allocation strategies and provide an understanding on how the exploration-exploitation tradeoff is affected by delays in observing the rewards. In randomized strategies, the extent of exploration-exploitation is controlled by a user-determined exploration probability sequence. In the presence of delayed rewards, one may choose between using the original exploration sequence that updates at every time point or update the sequence only when a new reward is observed, leading to two competing strategies. In this work, we show that while both strategies may lead to strong consistency in allocation, the property holds for a wider scope of situations for the latter. However, for finite sample performance, we illustrate that both strategies have their own advantages and disadvantages, depending on the severity of the delay and underlying reward generating mechanisms.
Accounting for confounding by time, early intervention adoption, and time-varying effect modification in the design and analysis of stepped-wedge designs: application to a proposed study design to reduce opioid-related mortality

Beginning in 2019, stepped-wedge designs (SWDs) were being used in the investigation of interventions to reduce opioid-related deaths in communities across the United States. However, these interventions are competing with external factors such as newly initiated public policies limiting opioid prescriptions, media awareness campaigns, and the COVID-19 pandemic. Furthermore, control communities may prematurely adopt components of the intervention as they become available. The presence of time-varying external factors that impact study outcomes is a well-known limitation of SWDs; common approaches to adjusting for them make use of a mixed effects modeling framework. However, these models have several shortcomings when external factors differentially impact intervention and control clusters. We discuss limitations of commonly used mixed effects models in the context of proposed SWDs to investigate interventions intended to reduce opioid-related mortality, and propose extensions of these models to address these limitations. We conduct an extensive simulation study of anticipated data from SWD trials targeting the current opioid epidemic in order to examine the performance of these models in the presence of external factors. We consider confounding by time, premature adoption of intervention components, and time-varying effect modification— in which external factors differentially impact intervention and control clusters. In the presence of confounding by time, commonly used mixed effects models yield unbiased intervention effect estimates, but can have inflated Type 1 error and result in under coverage of confidence intervals. These models yield biased intervention effect estimates when premature intervention adoption or effect modification are present. In such scenarios, models incorporating fixed intervention-by-time interactions with an unstructured covariance for intervention-by-cluster-by-time random effects result in unbiased intervention effect estimates, reach nominal confidence interval coverage, and preserve Type 1 error. Mixed effects models can adjust for different combinations of external factors through correct specification of fixed and random time effects. Since model choice has considerable impact on validity of results and study power, careful consideration must be given to how these external factors impact study endpoints and what estimands are most appropriate in the presence of such factors.
Procurement Mechanisms for Assortments of Differentiated Products

Many procurement agencies around the world construct assortments of differentiated products from which consumers can buy from. A leading example is framework agreements, a type of procurement mecha...
Computational catalyst discovery: Active classification through myopic multiscale sampling

The recent boom in computational chemistry has enabled several projects aimed at discovering useful materials or catalysts. We acknowledge and address two recurring issues in the field of computational catalyst discovery. First, calculating macro-scale catalyst properties is not straightforward when using ensembles of atomic-scale calculations [e.g., density functional theory (DFT)]. We attempt to address this issue by creating a multi-scale model that estimates bulk catalyst activity using adsorption energy predictions from both DFT and machine learning models. The second issue is that many catalyst discovery efforts seek to optimize catalyst properties, but optimization is an inherently exploitative objective that is in tension with the explorative nature of early-stage discovery projects. In other words, why invest so much time finding a "best" catalyst when it is likely to fail for some other, unforeseen problem? We address this issue by relaxing the catalyst discovery goal into a classification problem: "What is the set of catalysts that is worth testing experimentally?" Here, we present a catalyst discovery method called myopic multiscale sampling, which combines multiscale modeling with automated selection of DFT calculations. It is an active classification strategy that seeks to classify catalysts as "worth investigating" or "not worth investigating" experimentally. Our results show an ∼7-16 times speedup in catalyst classification relative to random sampling. These results were based on offline simulations of our algorithm on two different datasets: a larger, synthesized dataset and a smaller, real dataset.
Physics-inspired heuristics for soft MIMO detection in 5G new radio and beyond

Overcoming the conventional trade-off between throughput and bit error rate (BER) performance, versus computational complexity is a long-term challenge for uplink Multiple-Input Multiple-Output (MIMO) detection in base station design for the cellular 5G New Radio roadmap, as well as in next generation wireless local area networks. In this work, we present ParaMax, a MIMO detector architecture that for the first time brings to bear physics-inspired parallel tempering algorithmic techniques [28, 50, 67] on this class of problems. ParaMax can achieve near optimal maximum-likelihood (ML) throughput performance in the Large MIMO regime, Massive MIMO systems where the base station has additional RF chains, to approach the number of base station antennas, in order to support even more parallel spatial streams. ParaMax is able to achieve a near ML-BER performance up to 160 × 160 and 80 × 80 Large MIMO for low-order modulations such as BPSK and QPSK, respectively, only requiring less than tens of processing elements. With respect to Massive MIMO systems, in 12 × 24 MIMO with 16-QAM at SNR 16 dB, ParaMax achieves 330 Mbits/s near-optimal system throughput with 4--8 processing elements per subcarrier, which is approximately 1.4× throughput than linear detector-based Massive MIMO systems.
Computable obstructions to wait-free computability

We present an algorithmic test for deterministic wait-free solvability of decision tasks in asynchronous distributed systems whose processes communicate via read-write shared memory. Input to the test is a formal representation of the decision task as a triple (I, O, Δ), where I and O are simplicial complexes specifying the inputs and outputs of the task and Δ is the input-output relation of the task. The form of I, O, and Δ fixes the system size (i.e., number of processes). The result of the test is either (1) that there is no wait-free solution to the decision task for the given system size or (2) inconclusive Incompleteness of the test is unavoidable since wait-free solvability of decision tasks is undecidable for a system of size at least three. The test is shown to detect the impossibility of wait-free consensus for all systems, and experimental results show that the test detects the impossibility of wait-free set consensus for systems of size at most five. A more complete description of the efficacy of the test remains open. The key new ingredient underlying the test is a simplicial complex T, the task complex, associated to Δ. There is a simplicial projection map α from T to I, and α induces a homomorphism α * , from H * (T) to H * (I), where H * denotes simplicial homology. Failure of α * , to surject on H * (I) implies that no wait-free protocol can solve the task. Put another way, the elements of H * (I) that are not in the image of α * are obstructions to solvability of the task. These obstructions are computable when using suitable homology coefficients. By passing to quotients of T and I by well-behaved group actions, the test can be adapted to check the impossibility of solution of a decision task by any wait-free protocol that is symmetric or anonymous relative to the group.
Characterization of the nanomechanical properties of the fission yeast (Schizosaccharomyces pombe) cell surface by atomic force microscopy.

Variations in cell wall composition and biomechanical properties can contribute to the cellular plasticity required during complex processes such as polarized growth and elongation in microbial cells. This study utilizes atomic force microscopy (AFM) to map the cell surface topography of fission yeast, Schizosaccharomyces pombe, at the pole regions and to characterize the biophysical properties within these regions under physiological, hydrated conditions. High-resolution images acquired from AFM topographic scanning reveal decreased surface roughness at the cell poles. Force extension curves acquired by nanoindentation probing with AFM cantilever tips under low applied force revealed increased cell wall deformation and decreased cellular stiffness (cellular spring constant) at cell poles (17 ± 4 mN/m) relative to the main body of the cell that is not undergoing growth and expansion (44 ± 10 mN/m). These findings suggest that the increased deformation and decreased stiffness at regions of polarized growth at fission yeast cell poles provide the plasticity necessary for cellular extension. This study provides a direct biophysical characterization of the S. pombe cell surface by AFM, and it provides a foundation for future investigation of how the surface topography and local nanomechanical properties vary during different cellular processes.
Notes on two-dimensional pure supersymmetric gauge theories

In this note we study IR limits of pure two-dimensional supersymmetric gauge theories with semisimple non-simply-connected gauge groups including SU(k)/ℤk, SO(2k)/ℤ2, Sp(2k)/ℤ2, E6/ℤ3, and E7/ℤ2 for various discrete theta angles, both directly in the gauge theory and also in nonabelian mirrors, extending a classification begun in previous work. We find in each case that there are supersymmetric vacua for precisely one value of the discrete theta angle, and no supersymmetric vacua for other values, hence supersymmetry is broken in the IR for most discrete theta angles. Furthermore, for the one distinguished value of the discrete theta angle for which supersymmetry is unbroken, the theory has as many twisted chiral multiplet degrees of freedom in the IR as the rank. We take this opportunity to further develop the technology of nonabelian mirrors to discuss how the mirror to a G gauge theory differs from the mirror to a G/K gauge theory for K a subgroup of the center of G. In particular, the discrete theta angles in these cases are considerably more intricate than those of the pure gauge theories studied in previous papers, so we discuss the realization of these more complex discrete theta angles in the mirror construction. We find that discrete theta angles, both in the original gauge theory and their mirrors, are intimately related to the description of centers of universal covering groups as quotients of weight lattices by root sublattices. We perform numerous consistency checks, comparing results against basic group-theoretic relations as well as with decomposition, which describes how two-dimensional theories with one-form symmetries (such as pure gauge theories with nontrivial centers) decompose into disjoint unions, in this case of pure gauge theories with quotiented gauge groups and discrete theta angles.