cssi/SciSciGPT-SciSciNet huggingface dataset:
Quantifying the impact of services liberalization in a developing country

The authors consider how service liberalization differs from goods liberalization in terms of welfare, the level and composition of output, and factor prices within a developing economy, in this case Tunisia. Despite recent movements toward liberalization, Tunisian service sectors remain largely closed to foreign participation and are provided at high cost relative to many developing nations. The authors develop a computable general equilibrium (CGE) model of the Tunisian economy with multiple products and services and three trading partners. They model goods liberalization as the unilateral removal of product tariffs. Restraints on services trade involve both restrictions on cross-border supply (mode 1 in the GATS) and on foreign ownership through foreign direct investment (mode 3 in the GATS). The former are modeled as tariff-equivalent price wedges while the latter are comprised of both monopoly-rent distortions (arising from imperfect competition among domestic producers) and inefficiency costs (arising from a failure of domestic service providers to adopt least-cost practices). They find that goods-trade liberalization yields a gain in aggregate welfare and reorients production toward sectors of benchmark comparative advantage. However, a reduction of services barriers in a way that permits greater competition through foreign direct investment generates larger welfare gains. Service liberalization also requires lower adjustment costs, measured in terms of sectoral movement of workers, than does goods-trade liberalization. And it tends to increase economic activity in all sectors and raise the real returns to both capital and labor. The overall welfare gains of comprehensive service liberalization amount to more than 5 percent of initial consumption. The bulk of these gains come from opening markets for finance, business services, and telecommunications. Because these are key inputs into all sectors of the economy, their liberalization cuts costs and drives larger efficiency gains overall. The results point to the potential importance of deregulating services provision for economic development.
Implementing implicit OpenMP data sharing on GPUs

OpenMP is a shared memory programming model which supports the offloading of target regions to accelerators such as NVIDIA GPUs. The implementation in Clang/LLVM aims to deliver a generic GPU compilation toolchain that supports both the native CUDA C/C++ and the OpenMP device offloading models. There are situations where the semantics of OpenMP and those of CUDA diverge. One such example is the policy for implicitly handling local variables. In CUDA, local variables are implicitly mapped to thread local memory and thus become private to a CUDA thread. In OpenMP, due to semantics that allow the nesting of regions executed by different numbers of threads, variables need to be implicitly shared among the threads of a contention group. In this paper we introduce a re-design of the OpenMP device data sharing infrastructure that is responsible for the implicit sharing of local variables in the Clang/LLVM toolchain. We introduce a new data sharing infrastructure that lowers implicitly shared variables to the shared memory of the GPU. We measure the amount of shared memory used by our scheme in cases that involve scalar variables and statically allocated arrays. The evaluation is carried out by offloading to K40 and P100 NVIDIA GPUs. For scalar variables the pressure on shared memory is relatively low, under 26% of shared memory utilization for the K40, and does not negatively impact occupancy. The limiting occupancy factor in that case is register pressure. The data sharing scheme offers the users a simple memory model for controlling the implicit allocation of device shared memory.
Homogeneity of cohomology classes associated with Koszul matrix factorizations

In this work we prove the so-called dimension property for the cohomological field theory associated with a homogeneous polynomial with an isolated singularity, in the algebraic framework of [A. Polishchuk and A. Vaintrob, Matrix factorizations and cohomological field theories, J. Reine Angew. Math. 714 (2016), 1–122]. This amounts to showing that some cohomology classes on the Deligne–Mumford moduli spaces of stable curves, constructed using Fourier–Mukai-type functors associated with matrix factorizations, live in prescribed dimension. The proof is based on a homogeneity result established in [A. Polishchuk and A. Vaintrob, Algebraic construction of Witten’s top Chern class, in Advances in algebraic geometry motivated by physics (Lowell, MA, 2000) (American Mathematical Society, Providence, RI, 2001), 229–249] for certain characteristic classes of Koszul matrix factorizations of . To reduce to this result, we use the theory of Fourier–Mukai-type functors involving matrix factorizations and the natural rational lattices in the relevant Hochschild homology spaces, as well as a version of Hodge–Riemann bilinear relations for Hochschild homology of matrix factorizations. Our approach also gives a proof of the dimension property for the cohomological field theories associated with some quasihomogeneous polynomials with an isolated singularity.
Large embedded balls and Heegaard genus in negative curvature

We show if M is a closed, connected, orientable, hyperbolic 3-manifold with Heegaard genus g then g ≥ 1 cosh(r) where r denotes the radius of any isometrically embedded ball in M. Assuming an unpublished result of Pitts and Rubinstein improves this to g ≥ 1 cosh(r) + 1 . We also give an upper bound on the volume in terms of the flip distance of a Heegaard splitting, and describe isoperimetric surfaces in hyperbolic balls. AMS Classification 57M50; 57M27, 57N16
Progress on ELROI satellite license plate flight prototypes

The Extremely Low-Resource Optical Identifier (ELROI) beacon is a concept for a milliwatt optical "license plate" that can provide unique ID numbers for everything that goes into space. Using photon counting to enable extreme background rejection in real time, the ID number can be uniquely identified from the ground in a few minutes, even if the ground station detects only a few photons per second. The ELROI concept has been validated in long-range ground tests, and orbital prototypes are scheduled for launch in 2018 and beyond. We discuss the design and signal characteristics of these prototypes, including a PC-104 form factor unit which was integrated into a CubeSat and is currently scheduled to launch in May 2018, and basic requirements on ground stations for observing them. We encourage others to consider observing our test flights.
Driving Solar Giant Cells through the Self-organization of Near-surface Plumes

Global 3D simulations of solar giant-cell convection have provided significant insight into the processes which yield the Sun's observed differential rotation and cyclic dynamo action. However, as we move to higher resolution simulations a variety of codes have encountered what has been termed the convection conundrum. As these simulations increase in resolution and hence the level of turbulence achieved, they tend to produce weak or even anti-solar differential rotation patterns associated with a weak rotational influence (high Rossby number) due to large convective velocities. One potential culprit for this convection conundrum is the upper boundary condition applied in most simulations which is generally impenetrable. Here we present an alternative stochastic plume boundary condition which imposes small-scale convective plumes designed to mimic near-surface convective downflows, thus allowing convection to carry the majority of the outward solar energy flux up to and through our simulated upper boundary. The use of a plume boundary condition leads to significant changes in the convective driving realized in the simulated domain and thus to the convective energy transport, the dominant scale of the convective enthalpy flux, and the relative strength of the strongest downflows, the downflow network, and the convective upflows. These changes are present even far from the upper boundary layer. Additionally, we demonstrate that in spite of significant changes, giant cell morphology in the convective patterns is still achieved with self-organization of the imposed boundary plumes into downflow lanes, cellular patterns, and even rotationally-aligned banana cells in equatorial regions. This plume boundary presents an alternative pathway for 3D global convection simulations where driving is non-local and may provide a new approach towards addressing the convection conundrum.
Coronagraph-integrated wavefront sensing with a sparse aperture mask

Stellar coronagraph performance is highly sensitive to optical aberrations. In order to effectively suppress starlight for exoplanet imaging applications, low-order wavefront aberrations entering a coronagraph, such as tip-tilt, defocus, and coma, must be determined and compensated. Previous authors have established the utility of pupil-plane masks (both nonredundant/sparse-aperture and generally asymmetric aperture masks) for wavefront sensing (WFS). Here, we show how a sparse aperture mask (SAM) can be integrated with a coronagraph to measure low-order differential phase aberrations. Starlight rejected by the coronagraph’s focal plane stop is collimated to a relay pupil, where the mask forms an interference fringe pattern on a subsequent detector. Our numerical Fourier propagation models show that the information encoded in the fringe intensity distortions is sufficient to accurately discriminate and estimate Zernike phase modes extending from tip-tilt up to radial degree n=5, with amplitude up to λ/20 RMS. The SAM sensor can be integrated with both Lyot and shaped pupil coronagraphs at no detriment to the science beam quality. We characterize the reconstruction accuracy and the performance under low flux/short exposure time conditions, and place it in context of other coronagraph WFS schemes.
Erosion of a granular bed driven by laminar fluid flow

Motivated by examples of erosive incision of channels in sand, we investigate the motion of individual grains in a granular bed driven by a laminar fluid to give us new insights into the relationship between hydrodynamic stress and surface granular flow. A closed cell of rectangular cross-section is partially filled with glass beads and a constant fluid flux Q flows through the cell. The refractive indices of the fluid and the glass beads are matched and the cell is illuminated with a laser sheet, allowing us to image individual beads. The bed erodes to a rest height h r which depends on Q. The Shields threshold criterion assumes that the non-dimensional ratio θ of the viscous stress on the bed to the hydrostatic pressure difference across a grain is sufficient to predict the granular flux. Furthermore, the Shields criterion states that the granular flux is non-zero only for θ > θ c . We find that the Shields criterion describes the observed relationship h r ∝ Q 1/2 when the bed height is offset by approximately half a grain diameter. Introducing this offset in the estimation of 0 yields a collapse of the measured Einstein number q* to a power-law function of θ - θ c . with exponent 1.75 ± 0.25. The dynamics of the bed height relaxation are described well by the power-law relationship between the granular flux and the bed stress.
Contrastive Multiview Coding

Humans view the world through many sensory channels, e.g., the long-wavelength light channel, viewed by the left eye, or the high-frequency vibrations channel, heard by the right ear. Each view is noisy and incomplete, but important factors, such as physics, geometry, and semantics, tend to be shared between all views (e.g., a "dog" can be seen, heard, and felt). We investigate the classic hypothesis that a powerful representation is one that models view-invariant factors. We study this hypothesis under the framework of multiview contrastive learning, where we learn a representation that aims to maximize mutual information between different views of the same scene but is otherwise compact. Our approach scales to any number of views, and is view-agnostic. We analyze key properties of the approach that make it work, finding that the contrastive loss outperforms a popular alternative based on cross-view prediction, and that the more views we learn from, the better the resulting representation captures underlying scene semantics. Our approach achieves state-of-the-art results on image and video unsupervised learning benchmarks. Code is released at: this http URL.
Vortex rings drive entrainment and cooling in flow induced by a spark discharge

In spark plasma discharges, vortex rings are shown to control the expansion and convective cooling of the hot gas kernel. The rates of both processes increase with the electrical energy deposited. This has implications on momentum transport and passive scalar mixing in plasma-based flow and combustion control applications.
Operator growth bounds in a cartoon matrix model

We study operator growth in a model of N(N − 1)/2 interacting Majorana fermions that live on the edges of a complete graph of N vertices. Terms in the Hamiltonian are proportional to the product of q fermions that live on the edges of cycles of length q. This model is a cartoon “matrix model”: the interaction graph mimics that of a single-trace matrix model, which can be holographically dual to quantum gravity. We prove (non-perturbatively in 1/N and without averaging over any ensemble) that the scrambling time of this model is at least of order log N, consistent with the fast scrambling conjecture. We comment on apparent similarities and differences between operator growth in our “matrix model” and in the melonic models.
Directional clogging and phase separation for disk flow through periodic and diluted obstacle arrays

We model collective disk flow though a square array of obstacles as the flow direction is changed relative to the symmetry directions of the array. At lower disk densities there is no clogging for any driving direction, but as the disk density increases, the average disk velocity decreases and develops a drive angle dependence. For certain driving angles, the flow is reduced or drops to zero when the system forms a heterogeneous clogged state consisting of high density clogged regions coexisting with empty regions. The clogged states are fragile and can be unclogged by changing the driving angle. For large obstacle sizes, we find a uniform clogged state that is distinct from the collective clogging regime. Within the clogged phases, depinning transitions can occur as a function of increasing driving force, with intermittent motion appearing just above the depinning threshold. The clogging is robust against the random removal or dilution of the obstacle sites, and the disks are able to form system-spanning clogged clusters even under increasing dilution. If the dilution becomes too large, however, the clogging behavior is lost.
Energy-Aware Stochastic UAV-Assisted Surveillance

With the ease of deployment, capabilities of evading the jammers and obscuring their existence, unmanned aerial vehicles (UAVs) are one of the most suitable candidates to perform surveillance. There exists a body of literature in which the inspectors follow a deterministic trajectory to conduct surveillance, which results in a predictable environment for malicious entities. Thus, introducing randomness to the surveillance is of particular interest. In this work, we propose a novel framework for stochastic UAV-assisted surveillance that i) inherently considers the battery constraints of the UAVs, ii) proposes random moving patterns modeled via random walks, and iii) adds another degree of randomness to the system via considering probabilistic inspections. We formulate the problem of interest, i.e., obtaining the energy-efficient random walk and inspection policies of the UAVs subject to probabilistic constraints on inspection criteria of the sites and battery consumption of the UAVs, which turns out to be signomial programming that is highly non-convex. To solve it, we propose a centralized and a distributed algorithm along with their performance guarantee. This work contributes to both UAV-assisted surveillance and classic random walk literature by designing random walks with random inspection policies on weighted graphs with energy limited random walkers.
Object Detection Under Rainy Conditions for Autonomous Vehicles: A Review of State-of-the-Art and Emerging Techniques

Advanced automotive active safety systems, in general, and autonomous vehicles, in particular, rely heavily on visual data to classify and localize objects, such as pedestrians, traffic signs and lights, and nearby cars, to help the corresponding vehicles maneuver safely in their environments. However, the performance of object detection methods could degrade rather significantly in challenging weather scenarios, including rainy conditions. Despite major advancements in the development of deraining approaches, the impact of rain on object detection has largely been understudied, especially in the context of autonomous driving.
Quantum Q-Systems and Fermionic Sums—The Non-Simply Laced Case

In this paper, we seek to prove the equality of the $q$-graded fermionic sums conjectured by Hatayama et al. in its full generality, by extending the results of Di Francesco and Kedem to the non-simply laced case. To this end, we will derive explicit expressions for the quantum $Q$-system relations, which are quantum cluster mutations that correspond to the classical $Q$-system relations, and write the identity of the $q$-graded fermionic sums as a constant term identity. As an application, we will show that these quantum $Q$-system relations are consistent with the short exact sequence of the Feigin-Loktev fusion product of Kirillov-Reshetikhin modules obtained by Chari and Venkatesh.
An Investment-and-Marriage Model with Differential Fecundity: On the College Gender Gap

I build an investment-and-marriage model to provide a new explanation for the reversed college gender gap; that is, more women than men are going to college. The explanation is based on differentia...
Heuristic methods and performance bounds for photonic design.

In the photonic design problem, a scientist or engineer chooses the physical parameters of a device to best match some desired device behavior. Many instances of the photonic design problem can be naturally stated as a mathematical optimization problem that is computationally difficult to solve globally. Because of this, several heuristic methods have been developed to approximately solve such problems. These methods often produce very good designs, and, in many practical applications, easily outperform ‘traditional’ designs that rely on human intuition. Yet, because these heuristic methods do not guarantee that the approximate solution found is globally optimal, the question remains of just how much better a designer might hope to do. This question is addressed by performance bounds or impossibility results, which determine a performance level that no design can achieve. We focus on algorithmic performance bounds, which involve substantial computation to determine. We illustrate a variety of both heuristic methods and performance bounds on two examples. In these examples (and many others not reported here) the performance bounds show that the heuristic designs are nearly optimal, and can be considered globally optimal in practice. This review serves to clearly set up the photonic design problem and unify existing approaches for calculating performance bounds, while also providing some natural generalizations and properties.
Non-local entanglement and fast scrambling in de-Sitter holography

Abstract We study holographic entanglement and information scrambling in de-Sitter (dS) space in the context of the DS/dS correspondence. We find that our previously identified non-local entanglement structure of dS vacua can be extended out of the time-reflection symmetric slice. We extend the geometry to a two-sided configuration and calculate the zero-time mutual information between two intervals on different sides when there is a localized shock wave in the bulk. Interestingly, we find that the information scrambling time saturates the fast scrambler bound proposed by Sekino and Susskind and that the shock wave renders a wormhole to be traversable. Furthermore, we calculate a two-sided out-of-time-ordered correlator (OTOC) in the late time regime and we see that, before scrambling, it exponentially grows with an exponent whose value saturates the maximal bound of chaos proposed by Maldacena, Shenker and Stanford. At the end, we provide an explanation why the exponential growing of the late-time OTOC with the maximal bound of chaos saturated and the traversability of the wormhole are simple results of the non-local entanglement structure and we point out that this is a realization of the ER=EPR proposal.
Goodness-of-Fit Tests on Manifolds

We develop a general theory for the goodness-of-fit test to non-linear models. In particular, we assume that the observations are noisy samples of a submanifold defined by a sufficiently smooth non-linear map. The observation noise is additive Gaussian. Our main result shows that the “residual” of the model fit, by solving a non-linear least-square problem, follows a (possibly noncentral) $\chi ^{2}$ distribution. The parameters of the $\chi ^{2}$ distribution are related to the model order and dimension of the problem. We further present a method to select the model orders sequentially. We demonstrate the broad application of the general theory in machine learning and signal processing, including determining the rank of low-rank (possibly complex-valued) matrices and tensors from noisy, partial, or indirect observations, determining the number of sources in signal demixing, and potential applications in determining the number of hidden nodes in neural networks.
International Law in Black and White

Is the study of international law an art or a science? Can the role of international law be explained by general rules, with predictive value? Or does it require the exercise of judgment, in order to account for the richness and complexity of international life? Traditionally, international lawyers have gravitated to the latter view, analyzing issues in an essentially ad hoc and eclectic manner. In their controversial new book, The Limits of International Law, Jack Goldsmith and Eric Posner argue forcefully for a more scientific approach, relying on the methodology known as rational choice theory. The article examine the book's ambition to develop an overarching theory of international law, which reduces the role played by international law to a few simple explanatory models. In the end, Limits makes a convincing case that rational choice theory can help us better understand the development and effectiveness of international law. But the book provides no compelling reason why noninstrumental factors might not also play a role. It presents a flattened picture of the world, drained of texture and nuance and color. It illustrates that, to understand international law, we need not only science, but also art.
Derivatives and systemic risk: Netting, collateral, and closeout

Abstract In the U.S., as in most countries with well-developed securities markets, derivative securities enjoy special protections under insolvency resolution laws. Most creditors are “stayed” from enforcing their rights while a firm is in bankruptcy. However, many derivatives contracts are exempt from these stays. Furthermore, derivatives enjoy netting and closeout, or termination, privileges which are not always available to most other creditors. The primary argument used to motivate passage of legislation granting these extraordinary protections is that derivatives markets are a major source of systemic risk in financial markets and that netting and closeout reduce this risk. To date, these assertions have not been subjected to rigorous economic scrutiny. This paper critically re-examines this hypothesis. These relationships are more complex than often perceived. We conclude that it is not clear whether netting, collateral, and/or closeout lead to reduced systemic risk, once the impact of these protections on the size and structure of the derivatives market has been taken into account.
Banking Deregulations, Financing Constraints, and Firm Entry Size

WeexaminetheeffectofU.S.branchbankingderegulationsontheentrysizeofnewfirms,using micro-datafromtheU.S.CensusBureau.Wefindthattheaverageentrysizeforstartupsdidnot change following the deregulations. However, among firms that survived at least four years, a greater proportion of firms entered either at their maximum size or closer to the maximum size inthefirstyear.Themagnitudeoftheseeffectsweresmallcomparedtothemuchlargerchanges in entry rates of small firms following the reforms. Our results highlight that this large-scale entry at the extensive margin can obscure the more subtle intensive margin effects of changes in financing constraints. (JEL: E44, G21, L26, L43, M13)
Stock price manipulation, market microstructure and asymmetric information

In recent years, there has been a large literature on how stock exchange specialists set prices when there are investors who know more about the stock than they do. An important assumption in this literature is that there are *liquidity traders* who are equally likely to buy or sell for exogenous reasons. It is plausible that some buyers have cash needs and are forced to sell their stock. However, buyers will usually be able to choose the time at which they trade. It will be optimal for them to minimize the probability of trading with informed investors by choosing an appropriate time to trade and clustering at that time. This asymmetry means that when liquidity buyers are not clustering, purchases are more likely to be by an informed trader than sales so the price movement resulting from a purchase is larger than for a sale. As a result, profitable manipulation by uninformed investors may occur. A model where the specialist takes account of the possibility of manipulation in equilibrium is presented.
Why Kelo Is Not Good News for Local Planners and Developers

When the Supreme Court announced its 2005 decision in Kelo v. City of New London, few legal scholars were surprised at the outcome, which was premised on precedents extending back to the middle of the 19th century. Legal scholars were surprised, however, by the intense political reaction to Kelo (fueled substantially by Justice O'Connor's hyperbolic dissent), as property-rights advocates, legislators (at all levels of government), and media pundits assailed the ruling as a death knell for private property rights in America. Kelo's combination of relative legal insignificance and high political salience makes it an interesting case study in cross-institutional dynamics, i.e., the study of how the combination (and recombination) of political, legal, economic, and social forces determine the content of our laws. In this case, the Supreme Court's legal ruling in Kelo generated a political controversy, which is leading to legislative changes in the law. Those legislative changes, in turn, will affect future court decisions. The primary purpose of this article is to explain the aftermath of Kelo as a socio-legal phenomenon, which is every bit as important as (perhaps more important than) the Supreme Court's ruling in the case. By paying close attention to the political and legislative aftermath of Kelo, we can understand why the Supreme Court's decision is not good news for local planners and developers, who are finding it significantly more difficult to engage in urban (re)development throughout the United States. By contrast, the plaintiffs who lost the Kelo battle, may have won the war to keep their homes. This article also has a secondary purpose, which is the place Kelo and its political reception in a larger comparative-institutional context. That context (which I develop more fully in another article, Political Institutions, Private Property and Judicial Review: A Comparative Institutional Analysis, forthcoming in 2007 in the Supreme Court Economic Review) examines how political bodies, as well as courts, substantially protect private property rights. Kelo's aftermath, along with other evidence from the United Kingdom and the several U.S. states, supports the proposition that, even in the absence of constitutional protections assiduously enforced protected by judges, the institution of private property would be substantially protected.
Measuring fundamental galactic parameters with stellar tidal streams and SIM PlanetQuest

Extended halo tidal streams from disrupting Milky Way satellites offer new opportunities for gauging fundamental Galactic parameters without challenging observations of the Galactic center. In the roughly spherical Galactic potential, tidal debris from a satellite system is largely confined to a single plane containing the Galactic center, so accurate distances to stars in the tidal stream can be used to gauge the Galactic center distance, R0, given reasonable projection of the stream orbital pole on the XGC axis. Alternatively, a tidal stream with orbital pole near the YGC axis, such as the Sagittarius stream, can be used to derive the speed of the local standard of rest (ΘLSR). Modest improvements in current astrometric catalogs might allow this measurement to be made, but NASA's Space Interferometry Mission (now SIM PlanetQuest) can definitively obtain both R0 and ΘLSR using tidal streams.
Culture and Individual Judgment and Decision Making

Au cours des deux dernie`res de´cennies, on a beaucoup publie´ sur la culture et la psychologie interculturelle d’une part, sur le jugement et la prise de de´cision d’autre part (judgment and decision making: J/DM). Ces deux domaines ont e´te´ rapproche´s par peu de chercheurs dont on passe ici en revue les travaux. On s’inte´resse plus particulie`rement a` quatre the`mes J/DM qui ont e´te´ aborde´s d’un point de vue interculturel: l’e´valuation de la probabilite´, la perception du risque, l’attrait du risque et les formes de prise de de´cision. Notre investigation souligne une orientation positive dans les recherches J/DM interculturelles a` savoir le passage d’une simple description des diffe´rences nationales a` travers les comportements apparents a` l’examen des processus sous-jacents qui rendent compte de ces diffe´rences grâce au recours aux valeurs et aux perceptions marque´es par la culture. Pour encourager cette tendance, nous insistons pour que les futures e´tudes J/DM interculturelles soient davantage mode´lise´es (c’est-a`-dire qu’elles recherchent l’impact de V.I. changeant avec les cultures et ne se contentent pas de de´crire des diffe´rences entre groupes) et adoptent une approche en mosique dans le recueil des donne´es (c’est-a`-dire une approche qui fait appel a` des me´thodes diversifie´es et met en e´vidence des preuves convergentes pour retenir ou rejeter un mode`le).
Do We Need a Beanie Baby Fraud Statute

This Essay examines the appropriate line in legislative drafting between the overly generic fraud statute (e.g., mail fraud) and the addition of an overly specific statute, such as "Beanie Baby" fraud. Clearly, issues of federalism warrant consideration to determine whether the conduct belongs in the realm of the state and local prosecutor or more aptly in the federal system. Likewise, the scope of the federal statute needs to be clear in order to avoid ambiguity, overbreadth, and application of the Rule of Lenity. This Essay looks to a third factor for considering the propriety of the legislation: Whether the statute is designed to advance the historic roles provided to each of the three branches of government. When legislation accords a fair balancing to the executive, legislative, and judicial bodies, the appropriate line between the generic and specific statute is achieved.
Reverse shooting made easy: automating the search for the global nonlinear saddle path

We present the blueprints for a set of innovative reverse shooting algorithms that trap the global saddle path in systems with 2-4 state variables. The solution procedure is built around a new distance mapping and refined simplex algorithms. Since the algorithms are completely reliable and always work in the same way, we have been able to develop canned programs that solve for the global nonlinear saddle path in any model with 2-4 state variables. The programs are written in the spirit of plug and play: the user types in the equations of the model and then waits for the solution.
A Brief Overview of Fixed-Order Perturbative QCD Calculations of Jet Production in Heavy-Ion Collisions

We review recent developments in the QCD description of jet production and modification in reactions with heavy nuclei at relativistic energies. Our goal is to formulate a perturbative expansion in the presence of nuclear matter that allows to systematically improve the accuracy of the theoretical predictions. As an example, we present calculations of inclusive jet cross sections at RHIC, Z 0 /γ ∗ -tagged jet cross sections at the LHC, and jet shapes that include both next-to-leading order perturbative effects and the effects of the nuclear medium.
Querying datalog programs with temporal logic

Temporal logic queries on Datalog and negated Datalog programs are studied, and their relationship to Datalog queries on these programs is explored. It is shown that, in general, temporal logic queries have more expressive power than Datalog queries on Datalog and negated Datalog programs. It is also shown that anexistential domain-independent fragment of temporal logic queries has the same expressive power as Datalog queries on negated Datalog programs with inflationary semantics. This means that for finite structures this class of queries has the power of the fixpoint logic.
The Art of Criticism: How African Cartoons Discursively Constructed African Media Realities in the Post-Cold War Era

African newspaper cartoons are critical journalistic texts that are among the most visible manifestations of post-Cold War African political liberalisation. Since the early 1990s, cartoons have spearheaded the struggle for freedom of expression on the continent. One technique African cartoons have used to excoriate authoritarianism is to focus on political persecution of the media. This article is concerned with African cartoon narratives of the realities of the African media in the post-Cold War era. An analysis of a purposive sample of cartoons from countries where there have been major confrontations between governments and the media revealed that African political cartoons are irreverent counter-discourses that use African mythic idioms to portray a sombre picture of media realities on the African continent. The study also demonstrates that African political cartoonists resist abuses of power through deterritorialization and animalisation of authoritarian leaders who suppress freedom of expression. Fi...
A New Case for Direct Congressional Regulation of Guns in School Zones

This article suggests that in the wake of last year's school shootings at Columbine High School in Littleton, Colorado, Congress may justifiably exercise its commerce power to regulate arms in schools, notwithstanding its contrary holding in Lopez v. U.S in 1995. Sadly, with Columbine, the scope of violence in schools has assumed vastly more serious dimensions - to the point where such acts may accurately be labeled as premeditated acts of domestic terrorism. Under such circumstances, Congress may reasonably enact laws designed to curb the interstate market for weapons used in these attacks. If Congress concludes, for example, that imposing onerous federal penalties for carrying in schools such weapons - the component parts and raw materials of which traveled in interstate commerce - would convince a person who was otherwise considering purchasing the weapons not to consummate the transaction, the demand side of the market in diminished. As the Lopez Court itself notes, "We do not doubt that Congress has authority under the Commerce Clause to regulate numerous commercial activities that substantially affect interstate commerce and also affect the educational process."
The Incentives for Tax Planning

Abstract We use a proprietary data set with detailed executive compensation information to examine the relationship between the incentives of the tax director and GAAP and cash effective tax rates, the book-tax gap, and measures of tax aggressiveness. We find that the incentive compensation of the tax director exhibits a strong negative relationship with the GAAP effective tax rate, but little relationship with the other tax attributes. We interpret these results as indicating that tax directors are provided with incentives to reduce the level of tax expense reported in the financial statements.
Corruption and averting AIDS deaths

Abstract This paper looks at the impact of corruption on the effectiveness of antiretroviral drugs in preventing AIDS deaths and the potential channels that generate this relationship. This is based on a unique panel dataset of countries in sub-Saharan Africa, which combines information on all imported antiretroviral drugs (ARVs) from the World Health Organization’s Global Price Reporting Mechanism, with measures of corruption, estimates of the HIV prevalence, and the number of AIDS deaths in each year and in each country. Countries with higher levels of corruption experience a significantly smaller drop in AIDS deaths as a result of the same quantity of ARVs imported. This is robust to different measures of corruption and to a measure of overall death rates as well as HIV-specific death rates as the outcome. A case-study analysis of the Kenyan experience illustrates one potential mechanism for the observed effect, demonstrating that disproportionately more clinics begin distributing ARVs in areas that are predominantly represented by the new leader’s ethnic group.
Reasonable Risk Creation and Overinclusive Legislation

I argue that a given class of inchoate offenses -- which I call simple inchoate offenses -- are necessarily overinclusive, and inevitably punish persons whose conduct is reasonable. I illustrate this general problem by discussing drunk driving and drug possessory offenses. I conclude by describing and evaluating possible solutions to this injustice.
The qualitative dimension of Fourth Amendment `reasonableness'

Supreme Court doctrine protects two seemingly distinct kinds of interests under the heading of privacy rights: one "substantive," the other "procedural." The Fourth Amendment guarantee against "unreasonable searches and seizures" has been generally interpreted to protect procedural privacy. Searches are typically defined as governmental inspections of activities and locations in which an individual has a reasonable expectation of privacy from observation. In the typical case, this reasonable expectation of privacy may be breached only where the government has acquired a quantitatively substantial objective basis for believing that the search would uncover evidence of a crime. Substantive privacy rights have not normally been considered in this inquiry.This Article argues that a focus on the quantitative basis for finding probable cause is incomplete. As a corrective, Professor Colb urges a vision of the Fourth Amendment reasonableness requirement that contains both substantive and procedural safeguards. This critique of the quantitative approach to Fourth Amendment jurisprudence suggests that the Court ought to engage in substantively balancing the interests served by particular classes of searches and seizures against the costs of such government activity for the individual's sense of security and privacy, even in cases in which the government must also have probable cause and a warrant before proceeding. Such an integration of substantive and procedural privacy, one that engaged in a Fourth Amendment inquiry regarding the intrusiveness of a search or seizure, would more effectively further the privacy values embraced by the Court's criminal procedure and substantive constitutional precedents.
Do operating leases expand credit capacity? Evidence from borrowing costs and credit ratings

We document that borrowing costs and credit ratings are less sensitive to off-balance sheet lease financing than to on-balance sheet debt financing, particularly for firms that are financially constrained and firms that have limited ability to use tax shields. This evidence is consistent with theoretical predictions based on tax benefits as well as bankruptcy costs. Our evidence on borrowing costs and credit ratings suggests that credit markets treat operating leases differently from balance sheet debt. Consistent with this interpretation, we document that firms closer to ratings borderlines lease more, particularly around the investment grade borderline.
THE EFFECT OF INTERNATIONAL INSTITUTIONAL FACTORS ON PROPERTIES OF ACCOUNTING EARNINGS

Abstract International differences in the demand for accounting income predictably affect the way it incorporates economic income (change in market value) over time. We characterize the `shareholder’ and `stakeholder’ corporate governance models of common and code law countries respectively as resolving information asymmetry by public disclosure and private communication. Also, code law directly links accounting income to current payouts (to employees, managers, shareholders and governments). Consequently, code law accounting income is less timely, particularly in incorporating economic losses. Regulation, taxation and litigation cause variation among common law countries. The results have implications for security analysts, standard-setters, regulators, and corporate governance.
THE FULL COST OF INTERCITY HIGHWAY TRANSPORTATION

Abstract In this paper we review the theoretical and empirical literature on the cost structure of the provision of intercity highway transportation and specify and estimate our own cost functions. We develop a full cost model which identifies the key cost components and then estimate costs component by component: user costs, infrastructure costs, time and congestion costs, noise costs, accident costs, and pollution costs. The total long run average cost is $0.34 per vehicle km traveled. The single largest cost category is freeflow travel time. While the marginal cost of infrastructure is higher than its average cost, indicating that new construction is increasingly expensive, the marginal cost of driving (user fixed and variable costs) is less than the average cost, indicating that by increasing travel the user can spread his fixed cost of a vehicle over more trips without penalty.
Competitive equilibrium in a radial network

In a competitive market over a network with finite capacity, we can focus without loss of generality on simple allocations, where the net transaction over a link is equal to the gross transaction over the same link. If a simple allocation can be sustained by an equilibrium, then the allocation is efficient. If an equilibrium allocation is equivalent to a simple allocation and if the simple allocation is no longer sustained by an equilibrium, then the original equilibrium allocation is not efficient. For any efficient allocation, an equivalent simple allocation exists that can be sustained by a competitive equilibrium. Copyright 2003 by the RAND Corporation.
Cumulative Timed Intent: A New Predictive Tool for Technology Adoption:

Abstract Despite multiple calls for the integration of time into behavioral intent measurement, surprisingly little academic research has examined timed intent measures directly. In two empirical studies, the authors estimate individual-level cumulative adoption likelihood curves—curves calibrated on self-reported adoption likelihoods for cumulative time intervals across a fixed horizon—of 478 managerial decision makers, self-predicting whether and when they will adopt a relevant technology. A hierarchical Bayes formulation allows for a heterogeneous account of the individual-level adoption likelihood curves as a function of time and common antecedents of technology adoption. A third study generalizes these results among 354 consumer decision makers and, using behavioral data collected during a two-year longitudinal study involving a subsample of 143 consumer decision makers, provides empirical evidence for the accuracy of cumulative adoption likelihood curves for predicting whether and when a technology ...
What should classical liberal political economists do

In 1964 James Buchanan famously asked “What Should Economists Do?” He argued that economists should focus their intellectual attention on exchange and the institutions within which exchange takes place. This paper reflects on Buchanan’s message and looks at the development of that argument, and its implications in the wake of post-socialist political economy on the one hand, and the post-financial crisis of 2008 on the other. Following Buchanan, the paper argues that classical liberal political economists must embrace the intellectual and practical challenges of the day, and bring a robust theory of political economy to bear on questions of justice, questions of freedom and responsibility, and questions concerning the invisible hand and the appropriate institutional framework which results in peaceful social cooperation and productive specialization in a society of free and responsible individuals.
Women at the Bargaining Table: Pitfalls and Prospects

Research evidence across a number of disciplines and fields has shown that women can encounter both social and financial backlash when they behave assertively, for example, by asking for resources at the bargaining table. But this backlash appears to be most evident when a gender stereotype that prescribes communal, nurturing behavior by women is activated. In situations in which this female stereotype is suppressed, backlash against assertive female behavior is attenuated. We review several contexts in which stereotypic expectations of females are more dormant or where assertive behavior by females can be seen as normative. We conclude with prescriptions from this research that suggest how women might attenuate backlash at the bargaining table and with ideas about how to teach these issues of gender and backlash to student populations in order to make students, both male and female, more aware of their own inclination to backlash and how to rectify such inequities from both sides of the bargaining table.
The Right of Juvenile Offenders to be Punished: Some Implications of Treating Kids as Persons

At first glance, one may wonder how being subjected to punishment could ever be viewed as a "right" rather than an onus of the severest sort. If "rights" are claims that must be honored upon assertion, why would anyone in possession of his or her senses, even a youngster whose "senses" may be incompletely developed to begin with, ever demand to be punished? In this Article, I hope to answer such questions and demonstrate why recognition of the right to be punished might significantly advance the interests of certain juvenile offenders.This Article begins by sketching a theory of personhood and arguing that persons possess the right to be punished. Next, in contrast to traditional protectionist rights theory, the Article presents the claim that competent adolescents are autonomous "persons" who therefore possess the right to be punished. Finally, after presenting a theory for a constitutional right to be punished, the Article will examine some implications of such a right as it relates to the traditional juvenile justice system.