cssi/SciSciGPT-SciSciNet huggingface dataset:
Interacting bosons in an optical lattice

A strongly interacting Bose gas in an optical lattice is studied using a hard-core interaction. Two different approaches are introduced, one is based on a spin-1/2 Fermi gas with attractive interaction, the other one on a functional integral with an additional constraint (slave-boson approach). The relation between fermions and hard-core bosons is briefly discussed for the case of a one-dimensional Bose gas. For a three-dimensional gas we identify the order parameter of the Bose-Einstein condensate through a Hubbard-Stratonovich transformation and treat the corresponding theories within a mean-field approximation and with Gaussian fluctuations. This allows us to evaluate the phase diagram, including the Bose-Einstein condensate and the Mott insulator, the density-density correlation function, the static structure factor, and the quasiparticle excitation spectrum. The role of quantum and thermal fluctuations are studied in detail for both approaches, where we find good agreement with the Gross-Pitaevskii equation and with the Bogoliubov approach in the dilute regime. In the dense regime, which is characterized by the phase transition between the Bose-Einstein condensate and the Mott insulator, we discuss a renormalized Gross-Pitaevskii equation. This equation can describe the macroscopic wave function of the Bose-Einstein condensate in the dilute regime as well as close to the transition to the Mott insulator. Finally, we compare the results of the attractive spin-1/2 Fermi gas and those of the slave-boson approach and find good agreement for all physical quantities.
On Identifying a Massive Number of Distributions

Finding the underlying probability distributions of a set of observed sequences under the constraint that each sequence is generated i.i.d by a distinct distribution is considered. The number of distributions, and hence the number of observed sequences, are let to grow with the observation blocklength n. Asymptotically matching upper and lower bounds on the probability of error are derived.
Making Almost Commuting Matrices Commute

Suppose two Hermitian matrices A, B almost commute ({parallel}[A,B]{parallel} { 0 there exists a {delta} > 0, independent of the size N of the matrices, for which almost commuting implies being close to a commuting pair. However, this theorem does not specifiy how {delta} depends on {epsilon}. We give uniform bounds relating {delta} and {epsilon}. The proof is constructive, giving an explicit algorithm to construct A' and B'. We provide tighter bounds in the case of block tridiagonal and tridiagnonal matrices. Within the context of quantum measurement, this implies an algorithm to construct a basis in which we can make a projective measurement that approximately measures two approximately commuting operators simultaneously. Finally, we comment briefly on the case of approximately measuring three or more approximately commuting operators using POVMs (positive operator-valued measures) instead of projective measurements.
Axino LSP Baryogenesis and Dark Matter

We discuss a new mechanism for baryogenesis, in which the baryon asymmetry is generated by the lightest particle in another sector, for example the supersymmetric particle (LSP), decaying to quarks via baryonic-number-violating interactions. As a specic example, we use a supersymmetric axion model with an axino LSP and baryonic R-parity violation. This scenario predicts large R-parity violation for the stop, and an upper limit on the squark masses between 15 and 130 TeV, for dierent choices of the Peccei-Quinn scale and the soft Xt terms. We discuss the implications for the nature of dark matter in light of the axino
An asymptotic theory for randomly forced discrete nonlinear heat equations

We study discrete nonlinear parabolic stochastic heat equations of the form, $u_{n+1}(x) - u_n(x) = (\mathcal{L} u_n)(x) + \sigma(u_n(x))\xi_n(x)$, for $n\in {\mathbf Z}_+$ and $x\in {\mathbf Z}^d$, where ${\boldsymbol\xi}:=\{\xi_n(x)\}_{n\ge 0,x\in{\mathbf Z}^d}$ denotes random forcing and $\mathcal{L}$ the generator of a random walk on ${\mathbf Z}^d$. Under mild conditions, we prove that the preceding stochastic PDE has a unique solution that grows at most exponentially in time. And that, under natural conditions, it is “weakly intermittent.” Along the way, we establish a comparison principle as well as a finite support property.
Estimating reciprocal partition functions to enable design space sampling.

Reaction rates are a complicated function of molecular interactions, which can be selected from vast chemical design spaces. Seeking the design that optimizes a rate is a particularly challenging problem since the rate calculation for any one design is itself a difficult computation. Toward this end, we demonstrate a strategy based on transition path sampling to generate an ensemble of designs and reactive trajectories with a preference for fast reaction rates. Each step of the Monte Carlo procedure requires a measure of how a design constrains molecular configurations, expressed via the reciprocal of the partition function for the design. Although the reciprocal of the partition function would be prohibitively expensive to compute, we apply Booth’s method for generating unbiased estimates of a reciprocal of an integral to sample designs without bias. A generalization with multiple trajectories introduces a stronger preference for fast rates, pushing the sampled designs closer to the optimal design. We illustrate the methodology on two toy models of increasing complexity: escape of a single particle from a Lennard-Jones potential well of tunable depth and escape from a metastable tetrahedral cluster with tunable pair potentials.
Bayesian differential programming for robust systems identification under uncertainty.

This paper presents a machine learning framework for Bayesian systems identification from noisy, sparse and irregular observations of nonlinear dynamical systems. The proposed method takes advantag...
Zero-energy corner states in a non-Hermitian quadrupole insulator

We point out that in non-Hermitian systems, Jordan decomposition should replace eigendecomposition so that all ``good approximate eigenstates'' of the system are identified. These states can be resonantly excited. As a concrete example, we study the location and field distribution of zero-energy corner states in a non-Hermitian quadrupole insulator (QI) and split the parameter space into three distinct regimes according to properties of the corner states: near-Hermitian QI, intermediate phase, and trivial insulator. In the newly discovered intermediate phase, the Hamiltonian becomes defective, and the counterintuitive and delicate response of the system to external drives can be perfectly explained by the Jordan decomposition.
Characterizing several properties of high-dimensional random Apollonian networks

In this article, we investigate several properties of high-dimensional random Apollonian networks (HDRANs), including two types of degree profiles, the small-world effect (clustering property), sparsity, and three distance-based metrics. The characterizations of degree profiles are based on several rigorous mathematical and probabilistic methods, such as a two-dimensional mathematical induction, analytic combinatorics, and Polya urns, etc. The small-world property is uncovered by a well-developed measure---local clustering coefficient, and the sparsity is assessed by a proposed Gini index. Finally, we look into three distance-based properties; they are total depth, diameter and Wiener index.
Modeling techniques for logic locking

Logic locking is a method to prevent intellectual property (IP) piracy. However, under a reasonable attack model, SAT-based methods have proven to be powerful in obtaining the secret key. In response, many locking techniques have been developed to specifically resist this form of attack. In this paper, we demonstrate two SAT modeling techniques that can provide many orders of magnitude speed up in discovering the correct key. Specifically, we consider relaxed encodings and symmetry breaking. To demonstrate their impact, we model and attack a state-of-the-art logic locking technique, Full-Lock. We show that circuits previously unbreakable within 15 days of run time can be solved in seconds. Consequently, in assessing the strength of any given locking, it is imperative that these modeling techniques be considered. To remedy this vulnerability in the considered locking technique, we demonstrate an extended version, logic-enhanced Banyan locking, that is resistant to our proposed modeling techniques.
Stability analysis for cylindrical Couette flow of compressible fluids

A new analysis of basic Couette flow is based on an action principle for compressible fluids with a Hamiltonian as well as a kinetic potential. An effective criterion for stability recognizes the tensile strength of water. This interpretation relates the problem to capillary action and to metastable configurations (Berthelot’s negative pressure experiment of 1850). We calculate the pressure and density profiles and find that the first instability of basic Couette flow is localized near the bubble point. This theoretical prediction has been confirmed by recent experiments. The theory is the result of merging the two versions of classical hydrodynamics, as advocated by Landau for superfluid helium II. In an inspired paper, Landau, L. [“Theory of the superfluidity of helium II,” Phys. Rev. 60, 356–358 (1941)] introduced the idea of two independent flows, “phonons” and “rotons,” with strong emphasis on the idea that there is only one kind of fluid. The dynamical variables include two flows but only one density variable. In this paper, two-flow dynamics is created by merging two actions, neither by choosing between them nor by combining the two vector fields as in the Navier–Stokes equation. At rest, as contributions to the mass flow, they cancel, but a non-zero kinetic energy, kinetic potential, and non-zero angular momentum remain, and are manifest as liquid tension, as it is well known to exist through the observation of the meniscus and configurations with negative pressure. The immediate effect of merging the two versions of classical hydrodynamics in a unique theory based on an action principle is to provide a Hamiltonian and a kinetic potential for compressible fluids with rotational flow. This theory gives a very satisfactory characterization of the limit of stability of the most basic Couette flow. The inclusion of a vector field that is not a gradient has the additional effect of introducing spin, which explains a most perplexing experimental discovery: the ability of frozen helium to remember its angular momentum (spin).
Taming the prince: Bringing presidential emergency powers under law in Colombia

Can courts check presidential power exercised in a crisis—and should they? The case of Colombia, which recently turned on its head a history of presidential overreach and judicial rubber-stamping, provides an answer in the affirmative. As in much of Latin America, throughout Colombia’s post-independence history, bloodshed fueled authoritarian tendencies, with presidents exploiting the need for “order” to centralize power. One critical weapon in the presidential toolkit was the power to declare a state of emergency. During the twentieth century, these decrees became a routine pretext for the President to govern unilaterally, acquiesced to by the legislature and rarely challenged by the courts. That pattern has since come to an end. Since 1992, the Constitutional Court has proven an unexpectedly strong counterweight to presidential power, especially in its strict review of presidential emergency decrees. Under a model of substantive judicial review, the Constitutional Court has taken for itself the authority to review the factual basis giving rise to a crisis, and the adequacy of the President’s rationale for declaring it. Decrees that, as in the past, attempted to manufacture a crisis or which would exceed the President’s constitutional powers have been struck down. This paper discusses some of the Court’s successes in that ambit, and argues for the portability of this model to other national contexts.
Unknown Input Observers for Discretized Systems With Application to Networked Systems Corrupted by Sparse Malicious Packet Drops

Digital estimators for networked systems are proposed where the plant output measurements and control signals are corrupted by independent sparse malicious packet drop errors. The estimators comprise output sparse error approximators and unknown input observers (UIOs). The advantage of using digital estimators is that in many cases the condition for the existence of an UIO fails for continuous-time (CT) plants while it holds for discretized plants. A class of CT systems for which the existence condition for the UIO holds in the discrete-time (DT) domain is characterized. The proposed digital estimators are tested on a nonlinear networked control system (NCS). As part of our analysis, we study the existence of unknown input observers for discretized systems and show that discretization does not negatively impact the existence of UIOs and in some cases can facilitate the construction of UIOs when they do not exist for the CT systems.
Auto-Encoding Variational Bayes for Inferring Topics and Visualization

Visualization and topic modeling are widely used approaches for text analysis. Traditional visualization methods find low-dimensional representations of documents in the visualization space (typically 2D or 3D) that can be displayed using a scatterplot. In contrast, topic modeling aims to discover topics from text, but for visualization, one needs to perform a post-hoc embedding using dimensionality reduction methods. Recent approaches propose using a generative model to jointly find topics and visualization, allowing the semantics to be infused in the visualization space for a meaningful interpretation. A major challenge that prevents these methods from being used practically is the scalability of their inference algorithms. We present, to the best of our knowledge, the first fast Auto-Encoding Variational Bayes based inference method for jointly inferring topics and visualization. Since our method is black box, it can handle model changes efficiently with little mathematical rederivation effort. We demonstrate the efficiency and effectiveness of our method on real-world large datasets and compare it with existing baselines.
Network broadcast analysis and control of turbulent flows

We present a network-based modal analysis technique that identifies key dynamical paths along which perturbations amplify over a time-varying base flow. This analysis is built upon the Katz centrality, which reveals the flow structures that can effectively spread perturbations over a time-evolving network of vortical interactions on the base flow. Motivated by the resolvent form of the Katz function, we take the singular value decomposition of the resulting communicability matrix, complementing the resolvent analysis for fluid flows. The right-singular vectors, referred to as the broadcast modes, give insights into the sensitive regions where introduced perturbations can be effectively spread and amplified over the entire fluid-flow network that evolves in time. We apply this analysis to a two-dimensional decaying isotropic turbulence. The broadcast mode reveals that vortex dipoles are important structures in spreading perturbations. By perturbing the flow with the principal broadcast mode, we demonstrate the utility of the insights gained from the present analysis for effectively modifying the evolution of turbulent flows. The current network-inspired work presents a novel use of network analysis to guide flow control efforts, in particular for time-varying base flows.
Cobordism conjecture, anomalies, and the String Lamppost Principle

We consider consequences of triviality of cobordism classes and anomaly cancellation in supergravity theories in d > 6. We argue that this leads to the existence of certain defects which we call “I-folds” (a generalization of orientifolds). The requirement that compactifications to lower dimensions involving these defects be anomaly free leads to conditions on the higher dimensional theory. We show that in theories with 16 supercharges in d > 6 this leads to restrictions on the rank of the allowed gauge groups and thus provides an explanation for the observed restrictions in known string theory constructions. In particular, in eight and nine dimensions the only solutions to our constraints are precisely the ones realized in string theory compactifications. We also use these techniques to place constraints on the global structure of the gauge group in eight and nine dimensions.
Corporate Leverage and the Dynamics of Its Components

We investigate the dynamics of observed and target leverage ratios and deviations from the targets. The cross-sectional persistence in leverage ratios is driven by persistent targets, whereas time-series variation is driven by transitory deviations from targets. Consistent with dynamic trade-off theories, persistence is higher when the costs of deviating from targets are lower and when the adjustment costs are higher. Deviations are less persistent for firms that are over-levered and firms that are smaller, younger, or more focused or that have lower credit ratings. In recessions, excess leverage is less persistent for larger firms and is more persistent for smaller firms.
Productivity and the geographic concentration of industry: The role of plant scale

Abstract A large body of research has established a positive connection between an industry's productivity and the magnitude of its presence within locally defined geographic areas. This paper examines whether this relationship can be linked to a micro-level underpinning commonly associated with productivity: establishment scale. Looking at manufacturing industries across a sample of U.S. metropolitan areas, I find two primary results. First, average plant size increases substantially as an industry's employment in a metropolitan area rises. Second, the direct association between worker wages and local industry employment is more strongly associated with average plant size than the total number of plants, suggesting that localization economies may have significant organizational aspects.
Narrative Disclosure and Earnings Performance: Evidence from R&D Disclosures

ABSTRACT: This paper examines how earnings performance relates to firms' narrative R&D disclosure decisions. The unique nature of R&D investments and financial statements' limited ability to communicate the value of such investments highlight the role of narrative disclosure as a supplement to the financial statements. I predict and find that current earnings performance (adjusted for R&D expense) is negatively related to the quantity of narrative R&D disclosure. Conducting a content analysis of the detail, tone, and readability of narrative R&D disclosures, I find that managers adjust R&D disclosures based on earnings performance to provide relevant information rather than to obfuscate performance. Finally, I provide evidence that market participants find narrative R&D disclosure informative because it significantly affects sell-side analyst behavior, disclosure information content, and information asymmetry. Data Availability: Data are available from sources identified in the text.
"Love Don't Live Here Anymore": Economic Incentives for a More Equitable Model of Urban Redevelopment

The exclusion of poor, underprivileged people in urban renewal projects has been discussed in depth by a number of scholars. While this issue is far from resolved, the post-Katrina redevelopment plans provide an opportunity to re-evaluate notions of how to best redevelop urban spaces. In this Article, the author attempts to show that the interests of poor individuals can converge with those of city officials and developers in order to prevent the exclusion of the poor in post-Katrina New Orleans as well as future cities. To do so, the author relies on Law and Economics’ notion of the maximization of incentives and Critical Race Theory’s Interest Convergence Theory.
Price Competition and Endogenous Valuation in Search Advertising

Abstract This article studies how to endogenously assess the value of a “superior” advertising position in the price competition and examines the resulting location competition outcomes and price dispersion patterns. The authors consider a game-theoretic model in which firms compete for advertising positions and then compete in price for customers in a product market. Firms differ in their competence, and positions are differentiated in their prominence, which reflects consumers' online search behavior. They find that when endogenously evaluated within the product market competition, a prominent advertising position might not always be desirable for a firm with competitive advantage, even if it is cost-free. The profitability of a prominent advertising position depends on the trade-off between the extra demand from winning the position and the higher equilibrium prices when the weaker competitor wins it. Furthermore, the authors show that the bidding outcome might not align with the relative competitive s...
The Effect of Voluntary Clawback Adoptions on Corporate Tax Policy

ABSTRACT Companies are adopting executive compensation recoupment (“clawback”) policies to discourage aggressive financial reporting choices. Recent research suggests clawback policies encourage ot...
Public School Administrators and Technology Policy Making

Given little information about administrators' predilections toward participation in policy making, this study measured 256 midwestern principals' involvement in technology policy making at the building, district, state, and national levels. The study tested a conceptual model identifying influences on principals' involvement in technology policy making. Using hierarchical ordinary least squares regression analysis, administrators' disposition for participation set the stage for actual involvement at the building, district. and state levels. At the district, state, and national levels, involvement on a lower policy-making level was a strong predictor of involvement at a higher level. Principals' familiarity with the policy process was a predictor for involvement at the building level. Urban principals are less likely to become involved in technology policy making in their buildings and districts than suburban and rural principals are. Elementary principals are less likely to become involved in technology policy making than their high school and middle school counterparts.
Fiscal Federalism and Decentralization in India

This paper surveys the state of fiscal federalism in India, in the broader context of decentralization. We begin with an overview of the basic features and recent developments in intergovernmental fiscal relations, including the role of political institutions, the specifics of legislative and budgetary autonomy, assignments of expenditure responsibility and revenue authority, revenue collection mechanisms, the system of intergovernmental transfers, and institutions and mechanisms for borrowing by subnational units. We then provide a diagnosis of accountability mechanisms, examining their quality of functioning and distortions and constraints. In particular, we analyze to what extent, and through what mechanisms, lower-level governments are held accountable to higher-level governments, the extent to which policies of subnational governments are affected by the competition for mobile firms, taxpayers, and investment capital, the functioning of credit markets, including the responsiveness of subnational governments to credit ratings and bond yields, and the role of democratic electoral channels at national and subnational levels in providing accountability in the provision of subnational public goods. Next, we review the implications of the intergovernmental system and accountability mechanisms on the cooperation of subnational governments and the quality of service delivery. We examine the resources and capacity of the subnational entities that are responsible for key services such as water, sanitation, education and health care, and the impacts of decentralization on service quality and the distribution of benefits among elected officials, citizens and interest groups. Finally, we offer a concluding assessment with suggestions for reform priorities.
Natural language querying of historical databases

In this paper we examine the connection between two areas of semantics, namely the semantics of historical databases and the semantics of natural language querying, and link them together via a common view of the semantics of time. Since the target application domain is an historical database, we present the essential features of the Historical Relational Database Model (HRDM), an extension to the relational model motivated by the desire to incorporate more "real world" semantics into a database at the conceptual level. We then present the essential features of QE-III, a formally defined English database query language whose semantic and pragmatic theory, based on a Montague-type semantics, makes explicit reference to the notion of denotation with respect to a moment of time. We demonstrate the use of this language to query an example historical database, and discuss the issues of how to provide both a semantic and a pragmatic interpretation for questions within a model-theoretic framework.
Refinements and incentive efficiency in Walrasian models of insurance economies

Abstract The literature on Walrasian markets in large economies with adverse selection has used various equilibrium refinements, but has obtained no general incentive efficiency of equilibrium, namely when cross-subsidies are needed for efficiency. We show that the same refined equilibria may also be incentive inefficient even when general mechanisms that allow for such cross-subsidies are priced and can be traded. In the process, we also prove existence of some type of forward induction equilibria in this context.
The Benefits of a Relational Approach to Corporate Political Activity: Evidence from Political Contributions to Tax Policymakers

ABSTRACT: Empirical evidence linking campaign financing activity to future firm benefits is mixed. However, theory suggests that an important aspect of a successful political strategy is a multi-pe...
Market Liquidity and Funding Liquidity

We provide a model that links a security’s market liquidity — i.e., the ease of trading it — and traders’ funding liquidity — i.e., their availability of funds. Traders provide market liquidity and their ability to do so depends on their funding, that is, their capital and the margins charged by their financiers. In times of crisis, reductions in market liquidity and funding liquidity are mutually reinforcing, leading to a liquidity spiral. The model explains the empirically documented features that market liquidity (i) can suddenly dry up (i.e. is fragile), (ii) has commonality across securities, (iii) is related to volatility, (iv) experiences “flight to liquidity” events, and (v) comoves with the market. Finally, the model shows how the Fed can improve current market liquidity by committing to improve funding in a potential future crisis.
The Brennan Legacy: The Art of Judging

What does a judge do when he or she decides a case? Benjamin Cardozo posed this question in 1921 and answered it in what has become a classic of American legal literature: The Nature of the Judicial Process. Drawing from his wealth of scholarship and experience as Chief Judge of the New York Court of Appeals, he described the ingredients that enter "that strange compound which is brewed daily in the caldron of the courts." Cardozo's analysis and philosophy examined the accepted definition of the judicial process: What courts do and should do, and how judges reason and should reason in deciding particular cases. We paraphrase the broad question put by Cardozo three-quarters of a century ago, in the context of the Brennan philosophy of law, and attempt to answer these questions: What did William J. Brennan, Jr. do when he decided a case? What was the the Brennan "Art of Judging"? Is there a legacy from this art and, if so, who are its beneficiaries?
Does Anyone Get Stopped at the Gate? An Empirical Assessment of the Daubert Trilogy in the States

The Supreme Court's trilogy of evidence cases, Daubert, Joiner, and Kumho Tire, appear to mark a significant departure in the way scientific and expert evidence is handled in federal court. By focusing on the underlying methods used to generate the experts’ conclusions, Daubert has the potential to impose a more rigorous standard on experts. Given this potential, some individuals have called for states to adopt the Daubert standards to purge “junk science” from state courts. However, there is relatively little empirical support for the notion that Daubert affects the quality of expert evidence. Using a large data set of state court litigation, we examine whether state adoption of the Daubert standards has a systematic effect on the observable characteristics of experts retained in civil cases. We find very little evidence in support of a significant Daubert effect, even when we do a more detailed analysis of experts in products liability cases, an area of particular concern in the expert evidence debate. ...
Gonzales v. Carhart: Bringing Abortion Back into the Family Law Fold

Alone among abortion opinions, the U.S. Supreme Court’s second partial-birth abortion decision, Gonzales v. Carhart, included fetuses within the categories of human life and family relations. It spoke of a “bond” between a woman and her unborn “child.” Its analysis of constitutional law concerning abortion incorporated presumptions about parent-child relationships ordinarily applied only respecting already-born children: first that the law should prefer maintaining parent-child relationships; and second, that children are naturally vulnerable such that parents have a primary duty of protection, which will be supplemented by the state when a child’s welfare is seriously endangered. This article argues that Gonzales’ harmonizing of abortion law with family law has important and positive consequences not only for children’s health, but also for women and families in the areas of helping women to avoid unwanted pregnancies, and better accommodating women’s employment and other social commitments to women’s childbearing.
To starve or not to starve the beast

For thirty years, prominent voices have advocated a policy of starving the beast – cutting taxes to force government spending cuts. This paper analyzes the macroeconomic and welfare consequences of this policy using a two-country general equilibrium model. Under several strong assumptions, the policy, if fully implemented, produces domestic output and welfare gains accompanied by losses elsewhere. But negative effects can easily arise in the presence of longer policy implementation lags, utility-enhancing government spending, and productive government capital. Overall, the analysis finds no support for the idea that starving the beast is a foolproof way towards higher output and welfare.
The First Amendment and the Politics of Reproductive Health Care

More than forty years after Roe v. Wade and more than fifty years after Griswold v. Connecticut, nearly every aspect of reproductive rights remains intensely disputed. Courts continue to struggle with the scope of the constitutional right to abortion. Employers seek exemptions from generally applicable requirements to provide insurance coverage for contraception, re-opening questions about women’s need for contraception that once seemed well settled. Indeed, the very nature of abortion and contraception is contested: some consider them to be essential health care, whereas others consider them controversial moral choices. Drawing on recent controversies at the intersection of reproductive rights and First Amendment rights, this essay analyzes how the tendency to view reproductive health care as something other than “real” or “essential” health care has played out when courts are tasked with categorizing reproductive health-related speech for First Amendment purposes. Specifically, it demonstrates the schism that arises in the case law between judges that view reproductive health care as primarily medical and those that view it as something else — an elective procedure and thus a moral, political, or ideological choice. This essay also attempts to sketch a defense of the view that reproductive health care is essential, necessary, and therapeutic rather than merely the elective product of a moral choice.
Long-Horizon Returns

We use bootstrap simulations to examine the properties of long-horizon U.S. stock market returns. Distributions of continuously compounded returns converge toward normal distributions as we extend the horizon from one to 30 years, and distributions of dollar payoffs converge toward lognormal. We also show that, though largely irrelevant at short horizons, uncertainty about the expected return has a substantial impact on uncertainty about long-horizon payoffs.
WHICH MOMENTS TO MATCH

We describe an intuitive, simple, and systematic approach to generating moment conditions for generalized method of moments (GMM) estimation of the parameters of a structural model. The idea is to use the score of a density that has an analytic expression to define the GMM criterion. The auxiliary model that generates the score should closely approximate the distribution' of the observed data but is not required to nest it. If the auxiliary model nests the structural model then the estimator is as efficient as maximum likelihood. The estimator is advantageous when expectations under a structural model can be computed by simulation, by quadrature, or by analytic expressions but the likelihood cannot be computed easily.
Same-Sex Marriage and Taxes

Our tax system, while frequently criticized for its complexity, has the flexibility to encourage or influence behavior. It is used to try to influence people‘s spending habits to "jump-start" the economy or encourage businesses to buy more fixed assets. Tax law may even help to channel marital and family decisions. Frequently the proponents of same-sex marriage cite the difference in tax treatment as one of the reasons that same-sex couples receive discriminatory treatment. The tax code contains provisions that benefit only married individuals and families. These benefits provide hundreds to thousands of dollars in tax relief to individuals, but only if those individuals fall into prescribed categories. This article explores those categories, and the extent to which the preference for married couples with children furthers one of the goals of society, which is to perpetuate itself.
Effects-based operations and the law of aerial warfare

This article explores effects-based operations (EBO) to ascertain how they might affect the law of armed conflict. In light of the dominance of American military power, the U.S. approach to EBO, which is now reflected in the doctrine of other nations as well as the North Atlantic Treaty Organization (NATO), will serve as our model. Although EBO applies to every dimension of conflict, including the information sphere, it reaches its apogee in aerial warfare. Therefore, conflict in that medium will serve as the particular context of inquiry.
The resolution of failed banks during the crisis: Acquirer performance and FDIC guarantees, 2008–2013

Abstract We find that winning bidders in FDIC failed bank auctions from 2008 to 2013 experience substantial positive abnormal stock returns. Returns are inversely related to bid amounts after controlling for bid determinants, consistent with wealth transfers from the FDIC providing implicit subsidies to acquirers. The results challenge arguments that wealth transfers in earlier crises stemmed from since-eliminated bidding restrictions, but support the prediction of cash-in-the-market pricing theory that during crises, resolution through acquisition requires subsidization. Winning bid amounts are related to proxies for cash-in-the-market pricing. FDIC loss sharing, not widely used before the recent failure wave, is an important influence on bids.
Greek market efficiency and its international integration

Abstract Political, economic and legal risks are among the causes of market inefficiency and the consequent under-development of financial markets. To further the understanding of the factors affecting market development, this study evaluates the Athens Stock Exchange (ASE). The Greek market provides a unique opportunity to isolate market efficiency as a factor in market development. Since its membership to the European Union (EU) in 1981, political and legal risks in the Greek market are similar to those of the other EU member countries such as the U.K., Germany and France. Greece's inclusion in the Eurozone in 2000 has eliminated many of the economic risks. The unrealized potential of the ASE is therefore questioned. Considering the relatively small number of stocks in the ASE, market level analysis is potentially inappropriate: studies may be rejecting the ASE's efficiency due to irregularities in a few influential stocks. Thus, this study analyzes the efficiency of the ASE by evaluating the market's, as well as individual stocks’, returns. A well documented anomaly for the ASE, the day-of-the-week effect, is evaluated as are return predictability tests including a runs test, causality from other markets, and causality from liquidity. Both on the market level and on the individual level, evidence of inefficiencies are found. Based on the evidence that about 94% of Greek stocks’ returns are Granger-caused by at least one foreign market, it is concluded that the Greek market lacks the appeal for international diversification. Overall, the ASE's unrealized potential is blamed on lingering market inefficiencies and especially on its causal relationship with international markets.
Teaching programming skills to finance students: how to design and teach a great course

A motivated finance-major student should master at least one programming language. This is especially true for students from quantitative finance, business analytics, those attending a Master of Science in Finance or other financial engineering programs. Among the preferred languages, R holds one of the first places. This paper explains seven critical factors for designing and teaching a programming course: strong motivation, a good textbook, hands-on learning environment, being data intensive, a challenging term project, multiple supporting R datasets, and an easy way to upload such R datasets.
The determinants of bilateral trade

. In this paper we present a monopolistic competition model that incorporates asymmetric trade barriers and international differences in production costs. The model implies a highly non-linear bilateral trade equation. Estimation of this equation yields parameters for the elasticity of substitution and trade costs that are more reasonable than those found in previous studies. A simulation indicates that trade liberalization will shift trade from rich countries to poor countries and from within continental trading partners with preferential trade agreements to intercontinental trading partners. JEL Classification: F1 Les determinants du commerce bilateral. Ce memoire presente un modele de concurrence monopolistique qui postule des barrieres commerciales asymetriques et des differences internationales dans les couts de production. Le modele suggere une equation de commerce bilateral fortement non lineaire. La calibration de cette equation suggere des parametres pour l’elasticite de substitution et les couts de commerce qui sont plus raisonnables que ceux proposes dans des etudes anterieures. Une simulation indique que la liberalisation du commerce va deplacer le commerce des pays riches vers les pays pauvres, et des partenaires commerciaux intracontinentaux qui jouissent d’accords preferentiels vers les partenaires commerciaux intercontinentaux.
The Licensing of Market Development Rights within Technology Alliances: A Shareholder Value Perspective*

Technology alliances create market development rights that are shared between partners in an alliance relative to codeveloped product technology. Alliance partners will often manage the shared market development rights in a cooperative manner by forming an agreement in which one partner (i.e., the licensor) licenses its market development rights to the other partner in the alliance (i.e., the licensee). The real options and bargaining power literatures provide opposing recommendations regarding whether a licensor creates greater shareholder value by licensing its market development rights to the licensee on a more or less restrictive basis. Empirical analysis of technology alliance contracts reveals that the restrictiveness by which a licensor should license its market development rights to a licensee depends on the licensee's strategic marketing emphasis. Specifically, a licensee will create greater value by following a more restrictive distribution strategy when its partner's marketing strategy emphasizes value creation. Alternatively, a licensee will create greater value when its partner's marketing strategy emphasizes value appropriation by following a less restrictive distribution strategy. From a theoretical perspective, the paper's findings provide early evidence regarding the contribution of marketing strategy toward value creation in technology alliances and help resolve the differing expectations offered by the real options and bargaining power literatures. Managerially, the paper identifies an alliance partner's strategic marketing emphasis as a hitherto unrecognized factor determining when managers should follow a more or less restrictive distribution strategy when licensing marketing development rights within technology alliances.
A co-design framework of neural networks and quantum circuits towards quantum advantage.

Despite the pursuit of quantum advantages in various applications, the power of quantum computers in executing neural network has mostly remained unknown, primarily due to a missing tool that effectively designs a neural network suitable for quantum circuit. Here, we present a neural network and quantum circuit co-design framework, namely QuantumFlow, to address the issue. In QuantumFlow, we represent data as unitary matrices to exploit quantum power by encoding n = 2k inputs into k qubits and representing data as random variables to seamlessly connect layers without measurement. Coupled with a novel algorithm, the cost complexity of the unitary matrices-based neural computation can be reduced from O(n) in classical computing to O(polylog(n)) in quantum computing. Results show that on MNIST dataset, QuantumFlow can achieve an accuracy of 94.09% with a cost reduction of 10.85 × against the classical computer. All these results demonstrate the potential for QuantumFlow to achieve the quantum advantage. The advantages coming from involving quantum systems in machine learning are still not fully clear. Here, the authors propose a software/hardware co-design framework towards quantum-friendly neural networks showing quantum advantage, representing data as either random variables or numbers in unitary matrices.
When is it optimal to abandon a fixed exchange rate

The influential Krugman-Flood-Garber (KFG) model of balance of payment crises assumes that a fixed exchange rate is abandoned if and only if international reserves reach a critical threshold value. From a positive standpoint, the KFG rule is at odds with many episodes in which the central bank has plenty of international reserves at the time of abandonment. We study the optimal exit policy and show that from a normative standpoint, the KFG rule is generally suboptimal. We consider a model in which the fixed exchange rate regime has become unsustainable due to an unexpected increase in government spending. We show that when there are no exit costs, it is optimal to abandon immediately. When there are exit costs, the optimal abandonment time is a decreasing function of the size of the fiscal shock. For large fiscal shocks, immediate abandonment is optimal. Our model is consistent with evidence suggesting that many countries exit fixed exchange rate regimes with still plenty of international reserves in the central bank's vault. Copyright 2008, Wiley-Blackwell.
Hail Marriage and Farewell

It was elating to see the long-awaited victory for same-sex marriage pop up on my screen at 10:01 a.m. on June 26, 2015. It felt like a victory for rights, for open-mindedness, for love, and for the future. It was gratifying to see something I wasn’t sure I would get to see in my lifetime. I felt for a moment that I was living in a modern liberal state, where the state doesn’t get in the business of making moral judgments about people’s intimate choices in how they choose to organize their romantic and sexual lives. But it didn’t take long reading the opinion to see something many in the LGBT community warned people about along the way to marriage equality: that the price of admission to marriage for same-sex couples was the further reinforcement of a very traditional understanding of marriage and its role in society.1 Justice Kennedy’s decision for the majority in Obergefell v. Hodges2 is nothing if not a paean to a very traditional picture of marriage and its centrality in the social order.3 That may have been the cost of his vote: to get a conservative to sign onto same-sex marriage, perhaps we needed a conservative vision of romantic and sexual life in marriage. And maybe it was worth it, too; indeed, the two unmarried and one widowed women on the Court signed onto the opinion with nary a concurring or cautionary note. Costs aside, if we are going to have marriage at all, we can’t have marriage that excludes same-sex couples. Still, there is an important question that likely remains open after Obergefell. Although no one can doubt that same-sex couples now have a fundamental right to marry if and when the state offers marriage at all, one
Dominated Strategies and Common Knowledge

Abstract This paper establishes five results. First, the common knowledge of admissibility is not equivalent to iterated admissibility. Second, there exist games in which the common knowledge of admissibility does not uniquely determine which strategies should be eliminated on admissibility grounds. Third, there exist games in which assuming that admissibility is common knowledge yields a contradiction. Fourth, admissibility can be common knowledge without the players knowing the choice sets implied by this knowledge. Finally, difficulties with the common knowledge of admissibility can arise even in games in which each player has a unique dominant strategy.
International Health Emergencies in Failed and Failing States

Global health emergencies, particularly those occurring in failed and failing States, can become threats to the stability of the international community. This Article assesses the international mechanisms available to respond to such emergencies. After defining global health emergencies, it discusses the implications of global outbreaks in failed and failing States. It then examines the role played by the World Health Organization in controlling global health emergencies, with particular reference to the newly amended 2005 International Health Regulations and the Global Outbreak Alert and Response Network. Finally, it explores the role of other international organizations, including the United Nations Children’s Fund and the United Nations Office for the Coordination of Humanitarian Affairs, in addressing global health emergencies in failed or failing States. While no comprehensive and mandatory action plan exists to deal with global health emergencies, the tools developed by the World Health Organization and other international organizations are proving to be effective in dealing with global health emergencies so far. The lack of enforcement measures seems to be compensated by cooperation and voluntary actions by Member States, and significant non-State actor involvement. The lingering question is how to ensure that actions are taken in a timely and comprehensive manner in all global health emergencies.