cssi/SciSciGPT-SciSciNet huggingface dataset:
THE IMPACT OF THE MACROECONOMY ON HEALTH INSURANCE COVERAGE: EVIDENCE FROM THE GREAT RECESSION

This paper investigates the impact of the macroeconomy on the health insurance coverage of Americans using panel data from the Survey of Income and Program Participation for 2004-2010, a period that includes the Great Recession of 2007-2009. We find that a one percentage point increase in the state unemployment rate is associated with a 1.67 percentage point (2.12%) reduction in the probability that men have health insurance; this effect is strongest among college-educated, white, and older (50-64 years old) men. For women and children, health insurance coverage is not significantly correlated with the unemployment rate, which may be the result of public health insurance acting as a social safety net. Compared with the previous recession, the health insurance coverage of men is more sensitive to the unemployment rate, which may be due to the nature of the Great Recession.
Welfare for the Elderly: The Effects of SSI on Pre-Retirement Labor Supply

Abstract This paper studies pre-eligibility-age labor market disincentives created by the Supplemental Security Income (SSI) program. Asset and income limits might induce individuals nearing the eligibility age to work less. We exploit states’ supplementation of federal SSI benefits to estimate the effects of SSI on pre-retirement labor supply, using SIPP data. We find some evidence that generous SSI benefits reduce the pre-retirement labor supply (and earnings) of men who are likely to participate in SSI after retirement, as they near the eligibility age, especially men who are eligible for early Social Security benefits, which may be used to offset their reduced labor income.
Structuring Urban Redevelopment Projects: Moving Participants Up the Learning Curve

Urban redevelopment projects implemented through public-private partnerships are the preferred way to revitalize inner-city areas. As the numbers of participants increase and deal structures become...
Order Consolidation, Price Efficiency, and Extreme Liquidity Shocks

We show that the consolidation of orders is important for producing efficient prices, especially during times of high liquidity demand. The NYSE’s centralized opening call market performs better than Nasdaq’s decentralized opening process on typical trading days. The NYSE is much better than Nasdaq on witching days when index arbitrage activity subjects S&P 500 stocks to large, predictable, and mostly informationless order flow around quarterly futures contract expirations. Nasdaq opening price efficiency improves to NYSE levels once Nasdaq initiates a consolidated opening call in November 2004, but prices on the decentralized Nasdaq remain less efficient at other times of day.
Cannabis Legalization in State Legislatures: Public Health Opportunity and Risk

Cannabis is widely used in the U.S. and internationally despite its illicit status, but that illicit status is changing. In the U.S., 33 states and the District of Columbia have legalized medical cannabis, and 11 states and D.C. have legalized adult use cannabis. A majority of state medical cannabis laws and all but two state adult use laws are the result of citizen ballot initiatives, but state legislatures are beginning to seriously consider adult use legislation. From a public health perspective, cannabis legalization presents a mix of potential risks and benefits, but a legislative approach offers an opportunity to improve on existing legalization models passed using the initiative process that strongly favor business interests over public health. To assess whether state legislatures are acting on this opportunity, this article examines provisions of proposed adult use cannabis legalization bills active in state legislatures as of February 2019 to evaluate the inclusion of key public health best practices based on successful tobacco and alcohol control public health policy frameworks. Given public support for legalization, further adoption of state adult use cannabis laws is likely, but legalization should not be viewed as a binary choice between total prohibition and laissez faire commercialization. The extent to which adult use cannabis laws incorporate or reject public health best practices will strongly affect their impact, and health advocates should work to influence the construction of such laws to prioritize public health and learn from past successes and failures in regulating other substances.
Buyers as stakeholders: How relationships affect suppliers' financial constraints

Abstract This paper examines the role of buyer–supplier relationships on suppliers' financial constraints. Buyers are non-financial stakeholders with both the ability and incentive to monitor their supplier and act as a certifying agent. This mitigates agency costs, reducing the wedge between the costs of internal and external funds resulting in lower investment–cash flow sensitivity and lower cash–cash flow sensitivity. I provide empirical evidence for this effect. The results highlight the importance of understanding buyer–supplier relationships when evaluating a firm's financing and investment policy.
Dead Men Telling Tales: A Policy- Based Proposal for Survivability of Qui Tam Actions Under the Civil False Claims Act

The civil False Claims Act is the most powerful tool in the federal government's arsenal of weapons used to combat fraud, waste and abuse in government contracting. Because of the long statute of limitations of the civil False Claims Act, and the fact that a qui tam or whistleblower case brought under the civil False Claims Act can remain under seal while the federal government investigates it for many years, the whistleblower may die before the case is settled or litigated. Under the traditional common-law test for survivability of a federal statutory cause of action after a party's death, a court must first decide whether the statute is punitive or remedial. Generally, punitive actions are extinguished upon the death of a party, while remedial actions survive. This paradigm does not work well for qui tam cases brought under the Act, because the Act is both punitive and remedial. This article proposes adoption of a simpler test. The article proposes that the survivability of a cause of action brought by a whistleblower under the Act should depend solely on whether survivability would further the intent of Congress. The article suggests that survivability does further Congress' intent, and that there are sufficient safeguards in our justice system to ensure that defendants are not unduly prejudiced by the death of the whistleblower.
Did the Court Kill the Treason Charge?: Reassessing Cramer v. United States and Its Significance

In 1945, the United States Supreme Court decided a case involving a treason conviction for the first time in its history: Cramer v. United States. In that case, the Court explained what it meant to give aid and comfort to the enemy and interpreted the meaning of the overt act requirement under the Constitution's Treason Clause. Since the Court's decision, most observers have argued that Cramer's exacting standards made treason too hard to prove, thereby removing it as a potential charging option for federal prosecutors. Notably, between 1954 and 2006, the United States did not indict a single American for treason - the longest such absence in American history. However, in 2006, the United States indicted Adam Gadahn on charges of treason for his participation in several al-Qaeda videotapes. In light of this landmark indictment, this article reexamines the Court's decision in Cramer and its significance. In so doing, it challenges the conventional wisdom on two fronts. First, this article explores what issues motivated the Justices in Cramer. Specifically, it posits that the Court's decision (and division) can be best explained by the Justices' attitudes on two factors that have each been overlooked in previous scholarship: (1) the degree to which Congress may circumvent the Treason Clause by proscribing conduct covered by treason under a different heading and without the same procedural safeguards and (2) the degree to which the Framers intended treason prosecutions to be exceedingly rare and difficult. Second, this article reassesses the significance of Cramer and, in particular, its contribution to the lack of treason charges after 1954. In particular, it argues that while the Court's decision made treason harder to prove, it certainly did not make treason too hard to prove. Furthermore, it asserts that Cramer's most significant contribution was that it expressly held that Congress could criminalize (and the executive could prosecute) treasonous conduct under a separate statutory heading and without the procedural safeguards required by the Constitution's Treason Clause.
Comparing alternative explanations for accounting risk-return relations

Abstract Research into accounting risk-return relations largely relied on reference-based models of managerial choice. This focus ignores other explanations that may contribute to our understanding. Our study extends prior research by incorporating agency theory and implicit contracts theory into models based on the behavioral theory of the firm. We test our hypotheses in a large sample of US manufacturing firms in two different economic environments. Our results show some support for each theory, suggesting that multiple frameworks may better explain risk-return relations. Further, differences in results between the two economic environments imply that macroeconomic conditions may be important.
A Tale of Two Debt Crises: A Stochastic Optimal Control Analysis

Creditors, banks and bank regulators should evaluate whether a borrower is likely to default. I apply several techniques in the extensive mathematical literature of stochastic optimal control/dynamic programming to derive an optimal debt in an environment where there are risks on both the asset and liabilities sides. The vulnerability of the borrowing firm to shocks from either the return to capital, the interest rate or capital gain, increases in proportion to the difference between the Actual and Optimal debt ratio, called the excess debt. As the debt ratio exceeds the optimum, default becomes ever more likely. This paper is "A Tale of Two Crises" because the same analysis is applied to the agricultural debt crisis of the 1980s and to the subprime mortgage crisis of 2007. A measure of excess debt is derived, and we show that it is an early warning signal of a crisis in both cases.
A Multiple Pathway Anchoring and Adjustment (MPAA) Model of Attitude Generation and Recruitment

The Multiple Pathway Anchoring and Adjustment (MPAA) model integrates prior research on attitude formation, accessibility, strength, and attitude-behavior relationships and responds to key challenges to the traditional view of attitudes as enduring predispositions that guide behavior. The MPAA model emphasizes multiple pathways to attitude formation, including outside-in (object-centered) and inside-out (person-centered) pathways. The model also provides a nonoverlapping cognitions rationale for the coexistence of competing attitudes. The MPAA model introduces two subjective assessment criteria (representational and functional sufficiency) to explain how an anchoring and adjustment process functions to permit attitudes to guide behavior.
Smoothed Complexity of 2-player Nash Equilibria

We prove that computing a Nash equilibrium of a two-player ( $n\times n$ ) game with payoffs in [−1, 1] is PPAD-hard (under randomized reductions) even in the smoothed analysis setting, smoothing with noise of constant magnitude. This gives a strong negative answer to conjectures of Spielman and Teng [ST06] and Cheng, Deng, and Teng [CDT09]. In contrast to prior work proving PPAD-hardness after smoothing by noise of magnitude $1/\text{poly}(n)$ [CDT09], our smoothed complexity result is not proved via hardness of approximation for Nash equilibria. This is by necessity, since Nash equilibria can be approximated to constant error in quasi-polynomial time [LMM03]. Our results therefore separate smoothed complexity and hardness of approximation for Nash equilibria in two-player games. The key ingredient in our reduction is the use of a random zero-sum game as a gadget to produce two-player games which remain hard even after smoothing. Our analysis crucially shows that all Nash equilibria of random zero-sum games are far from pure (with high probability), and that this remains true even after smoothing.
Genome-wide ancestry and introgression in a Zambian baboon hybrid zone.

Hybridization in nature offers unique insights into the process of natural selection in incipient species and their hybrids. In order to evaluate the patterns and targets of selection, we examine a recently discovered baboon hybrid zone in the Kafue River Valley of Zambia, where Kinda baboons (Papio kindae) and grey-footed chacma baboons (P. ursinus griseipes) coexist with hybridization. We genotyped baboons at 14,962 variable genome-wide autosomal markers using double-digest RADseq. We compared ancestry patterns from this genome-wide data set to previously reported ancestry from mitochondrial-DNA and Y-chromosome sources. We also fit a Bayesian genomic cline model to scan for genes with extreme patterns of introgression. We show that the Kinda baboon Y chromosome has penetrated the species boundary to a greater extent than either mitochondrial DNA or the autosomal chromosomes. We also find evidence for overall restricted introgression in the JAK/STAT signalling pathway. Echoing results in other species including humans, we find evidence for enhanced and/or directional introgression of immune-related genes or pathways including the toll-like receptor pathway, the blood coagulation pathway, and the LY96 gene. Finally we show enhanced introgression and excess chacma baboon ancestry in the sperm tail gene ODF2. Together, our results elucidate the dynamics of introgressive hybridization in a primate system while identifying genes and pathways possibly under selection.
DialoGraph: Incorporating Interpretable Strategy-Graph Networks into Negotiation Dialogues

To successfully negotiate a deal, it is not enough to communicate fluently: pragmatic planning of persuasive negotiation strategies is essential. While modern dialogue agents excel at generating fluent sentences, they still lack pragmatic grounding and cannot reason strategically. We present DialoGraph, a negotiation system that incorporates pragmatic strategies in a negotiation dialogue using graph neural networks. DialoGraph explicitly incorporates dependencies between sequences of strategies to enable improved and interpretable prediction of next optimal strategies, given the dialogue context. Our graph-based method outperforms prior state-of-the-art negotiation models both in the accuracy of strategy/dialogue act prediction and in the quality of downstream dialogue response generation. We qualitatively show further benefits of learned strategy-graphs in providing explicit associations between effective negotiation strategies over the course of the dialogue, leading to interpretable and strategic dialogues.
Competition between fractional quantum Hall liquid and Wigner solid at small fillings: Role of layer thickness and Landau level mixing

The authors find signatures of magnetic-field-induced Wigner solids at small Landau level filling factors in two-dimensional electron systems confined to AlAs quantum wells.
An Improvement of Reed’s Treewidth Approximation

We present a new approximation algorithm for the treewidth problem which constructs a corresponding tree decomposition as well. Our algorithm is a faster variation of Reed’s classical algorithm. For the benefit of the reader, and to be able to compare these two algorithms, we start with a detailed time analysis for Reed’s algorithm. We fill in many details that have been omitted in Reed’s paper. Computing tree decompositions parameterized by the treewidth k is fixed parameter tractable (FPT), meaning that there are algorithms running in time O(f(k)g(n)) where f is a computable function, g(n) is polynomial in n, and n is the number of vertices. An analysis of Reed’s algorithm shows \(f(k) = 2^{O(k \log k)}\) and \(g(n) = n \log n\) for a 5-approximation. Reed simply claims time \(O(n \log n)\) for bounded k for his constant factor approximation algorithm, but the bound of \(2^{\varOmega (k \log k)} n \log n\) is well known. From a practical point of view, we notice that the time of Reed’s algorithm also contains a term of \(O(k^2 2^{24k} n \log n)\), which for small k is much worse than the asymptotically leading term of \(2^{O(k \log k)} n \log n\). We analyze f(k) more precisely, because the purpose of this paper is to improve the running times for all reasonably small values of k.
Counting Integer Points of Flow Polytopes

The Baldoni–Vergne volume and Ehrhart polynomial formulas for flow polytopes are significant in at least two ways. On one hand, these formulas are in terms of Kostant partition functions, connecting flow polytopes to this classical vector partition function, fundamental in representation theory. On the other hand, the Ehrhart polynomials can be read off from the volume functions of flow polytopes. The latter is remarkable since the leading term of the Ehrhart polynomial of an integer polytope is its volume! Baldoni and Vergne proved these formulas via residues. To reveal the geometry of these formulas, the second author and Morales gave a fully geometric proof for the volume formula and a partial generating function proof for the Ehrhart polynomial formula. The goal of the present paper is to provide a fully geometric proof for the Ehrhart polynomial formula for flow polytopes.
Longer-Run Effects of Anti-Poverty Policies on Disadvantaged Neighborhoods

We estimate the longer-run effects of minimum wages, the Earned Income Tax Credit, and welfare on key economic indicators of economic self-sufficiency in disadvantaged neighborhoods. Our strongest findings are twofold. First, the longer-run effects of the EITC are to increase employment and to reduce poverty and public assistance, as long as we rely on national as well as state variation in EITC policy. Second, tighter welfare time limits also reduce poverty and public assistance in the longer run; while the effect on public assistance result may be mechanically related to loss of benefits, the effect on poverty is more likely behavioral. It is harder to draw firm conclusions about minimum wages and welfare benefits. With some specifications and samples, the evidence suggests that higher minimum wages lead to longer-run declines in poverty and the share of families on public assistance, whereas higher welfare benefits have adverse longer-run effects. However, the evidence on minimum wages and welfare benefits is not robust – and the estimated effects of minimum wages are sometimes in the opposite direction, including when we restrict the analysis to more recent data that is likely of more interest to policymakers.
Rethinking tax priorities: Marriage neutrality, children, and contemporary families

Tax scholarship has long struggled with whether married taxpayers should be taxed differently from unmarried taxpayers. Currently, married taxpayers are subject to different tax rates than unmarried taxpayers, and may file a joint tax return. A married couple may pay a higher or lower amount of tax than an unmarried couple with the same total income, and a single person generally pays more tax on a given income than a married couple with a single earner with the same income. These outcomes are difficult to reconcile with a commitment to income tax progressivity, which in theory requires that higher incomes be taxed at higher rates. Moreover, the system penalizes some marriages, and benefits other marriages. This Article takes a fresh look at the problem of marriage bonuses and penalties, acknowledges that there may be difficulties with a separate filing system, but concludes that the joint return and special rates for married taxpayers should be abolished. In addition, drawing on the work of family law scholars, this Article argues that a stronger case can be made for supporting parenting rather than marriage in the tax system.
Statistical theory of cubic Langmuir turbulence

The cubic direct-interaction approximation is applied to the truncated cubically nonlinear Schroedinger equation. The statistical theory does a satisfactory job in several important respects.
Simultaneous averaging to zero by unitary mixing operators

We show that if every element a vector subspace of a C*-algebra can be averaged to zero by means of unitary mixing operators, then all the elements of the subspace can be simultaneously averaged to zero by a net of unitary mixing operators. Moreover, such subspaces admit a simple description in terms of commutators and kernels of states on the C*-algebra. We apply this result to center-valued expectations in C*-algebras with the Dixmier property.
Optimal Online Algorithms for File-Bundle Caching and Generalization to Distributed Caching

We consider a generalization of the standard cache problem called file-bundle caching, where different queries (tasks), each containing l ≥ 1 files, sequentially arrive. An online algorithm that does not know the sequence of queries ahead of time must adaptively decide on what files to keep in the cache to incur the minimum number of cache misses. Here a cache miss refers to the case where at least one file in a query is missing among the cache files. In the special case where l = 1, this problem reduces to the standard cache problem. We first analyze the performance of the classic least recently used (LRU) algorithm in this setting and show that LRU is a near-optimal online deterministic algorithm for file-bundle caching with regard to competitive ratio. We then extend our results to a generalized (h,k)-paging problem in this file-bundle setting, where the performance of the online algorithm with a cache size k is compared to an optimal offline benchmark of a smaller cache size h k. In this latter case, we provide a randomized O(l ln k/k-h)-competitive algorithm for our generalized (h, k)-paging problem, which can be viewed as an extension of the classic marking algorithm. We complete this result by providing a matching lower bound for the competitive ratio, indicating that the performance of this modified marking algorithm is within a factor of 2 of any randomized online algorithm. Finally, we look at the distributed version of the file-bundle caching problem where there are m ≥ 1 identical caches in the system. In this case, we show that for m = l + 1 caches, there is a deterministic distributed caching algorithm that is (l2 + l)-competitive and a randomized distributed caching algorithm that is O(l ln (2l + 1)-competitive when l ≥ 2. We also provide a general framework to devise other efficient algorithms for the distributed file-bundle caching problem and evaluate the performance of our results through simulations.
Deep fictitious play for stochastic differential games

In this paper, we apply the idea of fictitious play to design deep neural networks (DNNs), and develop deep learning theory and algorithms for computing the Nash equilibrium of asymmetric $N$-player non-zero-sum stochastic differential games, for which we refer as \emph{deep fictitious play}, a multi-stage learning process. Specifically at each stage, we propose the strategy of letting individual player optimize her own payoff subject to the other players' previous actions, equivalent to solve $N$ decoupled stochastic control optimization problems, which are approximated by DNNs. Therefore, the fictitious play strategy leads to a structure consisting of $N$ DNNs, which only communicate at the end of each stage. The resulted deep learning algorithm based on fictitious play is scalable, parallel and model-free, {\it i.e.}, using GPU parallelization, it can be applied to any $N$-player stochastic differential game with different symmetries and heterogeneities ({\it e.g.}, existence of major players). We illustrate the performance of the deep learning algorithm by comparing to the closed-form solution of the linear quadratic game. Moreover, we prove the convergence of fictitious play under appropriate assumptions, and verify that the convergent limit forms an open-loop Nash equilibrium. We also discuss the extensions to other strategies designed upon fictitious play and closed-loop Nash equilibrium in the end.
Random Coordinate Underdamped Langevin Monte Carlo

The Underdamped Langevin Monte Carlo (ULMC) is a popular Markov chain Monte Carlo sampling method. It requires the computation of the full gradient of the log-density at each iteration, an expensive operation if the dimension of the problem is high. We propose a sampling method called Random Coordinate ULMC (RC-ULMC), which selects a single coordinate at each iteration to be updated and leaves the other coordinates untouched. We investigate the computational complexity of RC-ULMC and compare it with the classical ULMC for strongly log-concave probability distributions. We show that RC-ULMC is always cheaper than the classical ULMC, with a significant cost reduction when the problem is highly skewed and high dimensional. Our complexity bound for RC-ULMC is also tight in terms of dimension dependence.
Computational semi-discrete optimal transport with general storage fees

Abstract We propose and analyze a modified damped Newton algorithm to solve the semi-discrete optimal transport with storage fees. We prove global linear convergence for a wide range of storage fee functions, the main assumption being that each warehouse's storage costs are independent. We show that if F is an arbitrary storage fee function that satisfies this independence condition then F can be perturbed into a new storage fee function so that our algorithm converges. We also show that the optimizers are stable under these perturbations. Furthermore, our results come with quantitative rates.
TreeFuser: A Framework for Analyzing and Fusing General Recursive Tree Traversals

Series of traversals of tree structures arise in numerous contexts: abstract syntax tree traversals in compiler passes, rendering traversals of the DOM in web browsers, kd-tree traversals in computational simulation codes. In each of these settings, a tree is traversed multiple times to compute various values and modify various portions of the tree. While it is relatively easy to write these traversals as separate small updates to the tree, for efficiency reasons, traversals are often manually fused to reduce the number of times that each portion of the tree is traversed: by performing multiple operations on the tree simultaneously, each node of the tree can be visited fewer times, increasing opportunities for optimization and decreasing cache pressure and other overheads. This fusion process is often done manually, requiring careful understanding of how each of traversals of the tree interact. This paper presents an automatic approach to traversal fusion: tree traversals can be written independently, and then our framework analyzes the dependences between the traversals to determine how they can be fused to reduce the number of visits to each node in the tree. A critical aspect of our framework is that it exploits two opportunities to increase the amount of fusion: i) it automatically integrates code motion, and ii) it supports partial fusion, where portions of one traversal can be fused with another, allowing for a reduction in node visits without requiring that two traversals be fully fused. We implement our framework in Clang, and show across several case studies that we can successfully fuse complex tree traversals, reducing the overall number of traversals and substantially improving locality and performance.
Age relationships of large-scale troughs and impact basins on Vesta

Abstract The Dawn mission at Asteroid 4 Vesta revealed two sets of enormous troughs with the Divalia Fossae spanning around two-thirds of the equator and the Saturnalia Fossae located in the northern hemisphere. Previous studies showed that the Divalia and Saturnalia Fossae are concentric around the Rheasilvia and Veneneia impact basins, respectively, and hence the troughs are widely considered to be genetically linked to the impact events forming the basins. In the existing literature, the troughs are assumed to be formed directly by, and simultaneously with the basin-forming impacts; however, the temporal relationships of the troughs and how they compare to the impact basins have never been documented. We count crater populations superposed on the Divalia and Saturnalia Fossae to establish their crater frequency distributions and compare that with the previously published data of the Rheasilvia and Veneneia basins, respectively. The comparisons allow us to determine the relative temporal relationships of the troughs and impact basins. Our results show that the Divalia Fossae and Rheasilvia basin overlap in their crater frequencies, indicating they can be considered coeval within the bounds of the uncertainties. A restrictive age relationship of the Saturnalia Fossae and Veneneia basin emplacement cannot be determined from the crater counts on Vesta since the preserved surface geology of the eastern Veneneia basin may not provide any meaningful information on the emplacement age of the impact structure. However, the Rheasilvia basin superposes the Veneneia basin, and thus the Veneneia basin-forming impact must predate that of Rheasilvia. The crater frequencies of the Saturnalia Fossae and Rheasilvia basin indicate that the Saturnalia Fossae are older than or coeval with the Rheasilvia basin emplacement. Taken together, our derived relative age relationships do not contradict but also do not yield tight constraints on the hypothesis that the basin-forming impacts on Vesta directly triggered the formation of the troughs.
Fu-Yau Hessian Equations

We solve the Fu–Yau equation for arbitrary dimension and arbitrary slope $\alpha^\prime$. Actually we obtain at the same time a solution of the open case $\alpha^\prime \gt 0$, an improved solution of the known case $\alpha^\prime \lt 0$, and solutions for a family of Hessian equations which includes the Fu–Yau equation as a special case. The method is based on the introduction of a more stringent ellipticity condition than the usual $\Gamma_k$ admissible cone condition, and which can be shown to be preserved by precise estimates with scale.
Quartermaster: a tool for modeling and simulating system degradation

It is essential that software systems be tolerant to degradations in components they rely on. There are patterns and techniques which software engineers use to ensure their systems gracefully degrade. Despite these techniques being available in practice, tuning and configuration is hard to get right and it is expensive to explore possible changes to components and techniques in complex systems. To fill these gaps, we propose Quartermaster to model and simulate systems and fault-tolerant techniques. We anticipate that Quartermaster will be useful to further research on graceful degradation and help inform software engineers about techniques that are most appropriate for their use cases.
Minimizing mean flow time with error constraint

We consider the problem of minimizing mean flow time for the Imprecise Computation Model introduced by Lin et al. A task system TS=({T i },{r(T i )},{d(T i )},{m(T i )},{o(T i )}) consists of a set of n independent tasks, where r(T i ),d(T i ),m(T i ) , and o(T i ) denote the ready time, deadline, execution time of the mandatory part, and execution time of the optional part of T i , respectively. Given a task system TS and an error threshold K , our goal is to find a preemptive schedule on one processor such that the average error is no more than K and the mean flow time of the schedule is minimized. Such a schedule is called an optimal schedule. In this article we show that the problem of finding an optimal schedule is NP-hard, even if all tasks have identical ready times and deadlines. A pseudopolynomial-time algorithm is given for a set of tasks with identical ready times and deadlines, and oppositely ordered mandatory execution times and total execution times (i.e., there is a labeling of tasks such that m(T i )≤ m(T i+1 ) and m(T i )+o(T i )≥ m(T i+1 )+o(T i+1 ) for each 1≤ i<n ). Finally, polynomial-time algorithms are given for (1) a set of tasks with identical ready times, and similarly ordered mandatory execution times and total execution times and (2) a set of tasks with similarly ordered ready times, deadlines, mandatory execution times, and total execution times.
Achieving High Throughput and Elasticity in a Larger-than-Memory Store

Millions of sensors, mobile applications and machines now generate billions of events. Specialized many-core key-value stores (KVSs) can ingest and index these events at high rates (over 100 Mops/s...
Stability of Vacuum for the Boltzmann Equation with Moderately Soft Potentials

We consider the spatially inhomogeneous non-cutoff Boltzmann equation with moderately soft potentials and any singularity parameter $$s\in (0,1)$$ , i.e. with $$\gamma +2s\in (0,2)$$ on the whole space $${\mathbb {R}}^3$$ . We prove that if the initial data $$f_{{{\,\mathrm{in}\,}}}$$ are close to the vacuum solution $$f_{\text {vac}}=0$$ in an appropriate weighted norm then the solution f remains regular globally in time and approaches a solution to a linear transport equation. Our proof uses $$L^2$$ estimates and we prove a multitude of new estimates involving the Boltzmann kernel without angular cut-off. Moreover, we rely on various previous works including those of Gressman–Strain, Henderson–Snelson–Tarfulea and Silvestre. From the point of view of the long time behavior we treat the Boltzmann collisional operator perturbatively. Thus an important challenge of this problem is to exploit the dispersive properties of the transport operator to prove integrable time decay of the collisional operator. This requires the most care and to successfully overcome this difficulty we draw inspiration from Luk’s work [Stability of vacuum for the Landau equation with moderately soft potentials, Annals of PDE (2019) 5:11] and that of Smulevici [Small data solutions of the Vlasov-Poisson system and the vector field method, Ann. PDE, 2(2):Art. 11, 55, 2016]. In particular, to get at least integrable time decay we need to consolidate the decay coming from the space-time weights and the decay coming from commuting vector fields.
No Excess Mortality Detected in Rural Bangladesh in 2020 From Repeated Surveys of a Population of 81,000

Background: Excess mortality has demonstrated under-counting of COVID-19 deaths in many countries but cannot be measured in low-income countries where civil registration is incomplete. Methods: Enumerators conducted an in-person census of all 16,054 households in a sample of 135 villages within a 350 km2 region of Bangladesh followed by a census conducted again in May and November 2020 over the phone. The date and cause of any changes in household composition, as well as changes in income and food availability, were recorded. For analysis, we stratify the mortality data by month, age, gender, and household education. Mortality rates were modeled by Bayesian multilevel regression and the strata aggregated to the population by poststratification. Findings: A total of 276 deaths were reported between February and the end of October 2020 for the subset of the population that could be contacted twice over the phone, slightly below the 289 deaths reported for the same population over the same period in 2019. After adjustment for survey non-response and poststratification, 2020 mortality changed by -8\% (95\% CI, -21\% to 7\%) relative to an annualized mortality of 6.1 per thousand in 2019. However, salaried breadwinners reported a 40\% decline in income and businesses a 60\% decline in profits in May 2020. Interpretation: All-cause mortality in the surveyed portion of rural Bangladesh was if anything lower in 2020 compared to 2019. Our findings suggest various restrictions imposed by the government limited the scale of the pandemic, although they need to be accompanied by expanded welfare programs. Funding Statement: The study was supported by the U.S. National Science Foundation. Declaration of Interests: The authors have no competing interests to declare. Ethics Approval Statement: Institutional Review Boards at both Michigan State University and Columbia University, as well as the NGO Bureau of Bangladesh, approved the study.
The Contestation of Tech Ethics: A Sociotechnical Approach to Ethics and Technology in Action

Recent controversies related to topics such as fake news, privacy, and algorithmic bias have prompted increased public scrutiny of digital technologies and soul-searching among many of the people associated with their development. In response, the tech industry, academia, civil society, and governments have rapidly increased their attention to “ethics” in the design and use of digital technologies (“tech ethics”). Yet almost as quickly as ethics discourse has proliferated across the world of digital technologies, the limitations of these approaches have also become apparent: tech ethics is vague and toothless, is subsumed into corporate logics and incentives, and has a myopic focus on individual engineers and technology design rather than on the structures and cultures of technology production. As a result of these limitations, many have grown skeptical of tech ethics and its proponents, charging them with “ethics-washing”: promoting ethics research and discourse to defuse criticism and government regulation without committing to ethical behavior. By looking at how ethics has been taken up in both science and business in superficial and depoliticizing ways, I recast tech ethics as a terrain of contestation where the central fault line is not whether it is desirable to be ethical, but what “ethics” entails and who gets to define it. This framing highlights the significant limits of current approaches to tech ethics and the importance of studying the formulation and real-world effects of tech ethics. In order to identify and develop more rigorous strategies for reforming digital technologies and the social relations that they mediate, I describe a sociotechnical approach to tech ethics, one that reflexively applies many of tech ethics’ own lessons regarding digital technologies to tech ethics itself.
Stronger calibration lower bounds via sidestepping

We consider an online binary prediction setting where a forecaster observes a sequence of T bits one by one. Before each bit is revealed, the forecaster predicts the probability that the bit is 1. The forecaster is called well-calibrated if for each p ∈ [0, 1], among the np bits for which the forecaster predicts probability p, the actual number of ones, mp, is indeed equal to p · np. The calibration error, defined as ∑p |mp − p np|, quantifies the extent to which the forecaster deviates from being well-calibrated. It has long been known that an O(T2/3) calibration error is achievable even when the bits are chosen adversarially, and possibly based on the previous predictions. However, little is known on the lower bound side, except an Ω(√T) bound that follows from the trivial example of independent fair coin flips. In this paper, we prove an Ω(T0.528) bound on the calibration error, which is the first super-√T lower bound for this setting to the best of our knowledge. The technical contributions of our work include two lower bound techniques, early stopping and sidestepping, which circumvent the obstacles that have previously hindered strong calibration lower bounds. We also propose an abstraction of the prediction setting, termed the Sign-Preservation game, which may be of independent interest. This game has a much smaller state space than the full prediction setting and allows simpler analyses. The Ω(T0.528) lower bound follows from a general reduction theorem that translates lower bounds on the game value of Sign-Preservation into lower bounds on the calibration error.
Incorporating learning-by-doing into mixed complementarity equilibrium models

Abstract Market equilibrium models are often specified and solved as mixed complementarity problems (MCPs). These formulations combine the Karush–Kuhn–Tucker (KKT) optimality conditions of the optimization problems faced by multiple strategic players with market-clearing conditions, such that the solution to this system provides the Nash equilibrium prices and quantities. MCPs are widely applied to energy markets including those for electricity, oil, and natural gas. While researchers have made substantial progress on expanding the model features included in MCPs and on solving these problems, a limitation of existing MCPs is that they treat costs as exogenous input parameters. Therefore, MCPs have not been able to capture learning-by-doing (LBD), the empirically observed phenomenon whereby production costs tend to decline as a function of cumulative production experience. In this paper, we demonstrate the incorporation of LBD into a mixed complementarity equilibrium model. We consider two closely related, but nevertheless distinct, LBD formulations: one with discrete changes in cost from period to period, and another where cost declines continuously. Through theoretical analysis and numerical exploration, we establish the conditions under which these LBD formulations lead to convex optimization problems. Confirming convexity is important because it guarantees that their KKT conditions are sufficient for optimality. Then, we demonstrate the practical application of a mixed complementarity equilibrium model with LBD using the North American natural gas market as an example. When LBD is incorporated into the cost of liquefaction, North America exports more liquefied natural gas, which raises prices and reduces domestic consumption.
Cannot Predict Comment Volume of a News Article before (a few) Users Read It.

Many news outlets allow users to contribute comments on topics about daily world events. News articles are the seeds that spring users' interest to contribute content, i.e., comments. An article may attract an apathetic user engagement (several tens of comments) or a spontaneous fervent user engagement (thousands of comments). In this paper, we study the problem of predicting the total number of user comments a news article will receive. Our main insight is that user-to-user interaction factors contribute the most to an accurate prediction, while news article specific factors have surprisingly little influence. This appears to be an interesting and understudied phenomenon: collective social behavior at a news outlet shapes user response and may even downplay the content of an article. We compile and analyze a large number of features, both old and novel from literature. The features span a broad spectrum of facets including news article and comment contents, temporal dynamics, sentiment/linguistic features, and user behaviors. We show that the early arrival rate of comments is the best indicator of the eventual number of comments. We conduct an in-depth analysis of this feature across several dimensions, such as news outlets and news article categories. We show that the relationship between the early rate and the final number of comments as well as the prediction accuracy vary considerably across news outlets and news article categories (e.g., politics, sports, or health).
Large Clique is Hard on Average for Resolution

We prove an \(\exp ({\varOmega (k^{(1-\epsilon )})})\) resolution size lower bound for the k-Clique problem on random graphs, for (roughly speaking) \(k<n^{1/3}\). Towards an optimal resolution lower bound of the problem (i.e. of type \(n^{\varOmega (k)}\)), we also extend the \(n^{\varOmega (k)}\) bound in [2] on regular resolution to a stronger model called a-irregular resolution, for \(k<n^{1/3}\). This model is interesting in that all known CNF families separating regular resolution from general [1, 24] have short proofs in it.
Partisanship and public opinion on cash transfers: survey evidence from Kenya

How does public opinion on the causes of poverty and deservingness condition support for government support for the poor? This article answers this question with a focus on direct cash transfers in...
Two-dimensional local Hamiltonian problem with area laws is QMA-complete

Abstract We show that the two-dimensional (2D) local Hamiltonian problem with the constraint that the ground state obeys area laws is QMA -complete. We also prove similar results in 2D translation-invariant systems and for the 3D Heisenberg and Hubbard models with local magnetic fields. Consequently, unless MA = QMA , not all ground states of 2D local Hamiltonians with area laws have efficient classical representations that support efficient computation of local expectation values. In the future, even if area laws are proved for ground states of 2D gapped systems, the computational complexity of these systems remains unclear.
Three-dimensional simulations of Marangoni-Benard convection in small containers by the least-squares finite element method

Abstract This paper reports a numerical study of the Marangoni-Benard (MB) convection in a planar fluid layer. The least-squares finite element method (LSFEM) is employed to solve the three-dimensional Stokes equations and the energy equation. First, the governing equations are reduced to be first-order by introducing variables such as vorticity and heat fluxes. The resultant first-order system is then cast into a div-curl-grad formulation, and its ellipticity and boundary conditions are illustrated. This numerical approach provides an equal-order discretization for velocity, pressure, vorticity, temperature and heat conduction fluxes. Numerical results reported include the critical Marangoni numbers (Mac) for the onset of the convection in containers with various aspect ratios, and the planforms of supercritical MB flows. The numerical solutions compared favorably with the experimental results reported by Koschmieder and Prahl.
Are High-Redshift Quasars Hidden by Dusty Galaxies?

A Monte Carlo technique has been developed to compute the joint probability distribution for the reddening and extinction of quasars by galaxies along the line of sight with a realistic dust extinction curve including the 220 nm feature. Galaxies are treated as disks with random inclinations, having exponential or modified Gaussian radial profiles. This technique is used to find the distribution of the reddened quasars on multicolor diagrams such as the (U-J, J-F) plots used by Koo and Kron (1982) to find faint quasars. The multicolor search technique is not a simple UV excess approach, and the resulting color selection does not add significantly to the flux selection discussed by Wright (1981), Ostriker and Heisler (1984), and Heisler and Ostriker (1988). The quasar reddening trend observed by Wright and Malkan (1987) is about 0.35 + or - 0.50 times the mean reddening of the selected sample predicted by the Heisler and Ostriker model.
The Effect of a Gravity Wave Drag Parameterization Scheme on GLA Fourth Order GCM Forecasts

Ten-day forecast experiments have been performed to determined whether the introduction of a simple orographic gravity wave drag scheme into a fourth-order GCM would reduce the climate drift of the fine resolution model and improve the model's medium range predictive skill. Error reduction due to the gravity waves is found in stratospheric predictions, where the improvement is confined mainly to the zonal mean component. Improvements are noted in the Northern Hemisphere climatology, where low level westerlies are weakened and shifted poleward, and in the Southern Hemisphere, where the roaring forties and fifties are better simulated.