cssi/SciSciGPT-SciSciNet huggingface dataset:
Separation conditions and criteria for uniform approximation of input–output maps

We consider multidimensional shift-invariant input–output maps G from a relatively compact set of functions S to a set of real-valued functions, and we give criteria under which these maps can be uniformly approximated arbitrarily well using a certain structure consisting of a not-necessarily linear dynamic part followed by a non-linear memoryless section that may contain sigmoids or radial basis functions, etc. The dynamic part is comprised of a finite number of dynamic maps h1,…,hj drawn from a set H of maps that satisfy a certain continuity condition. In our results certain separation conditions, of the kind associated with the Stone–Weierstrass theorem, play a prominent role. Here they emerge as criteria for approximation, and not just sufficient conditions under which an approximation exists. In particular, one of the theorems given is a result to the effect that universal approximation can be achieved using the structure we consider if and only if the set H satisfies the separation condition that (hu1)(0)≠(hu2)(0) for some h∈H whenever u1,u2∈cl(S) and u1≠u2 (where cl(S) denotes the closure of S). This holds even if the elements of H are not linear. © 1998 John Wiley & Sons, Ltd.
On the Failure of the Bootstrap for Matching Estimators

Matching estimators are widely used in empirical economics for the evaluation of programs or treatments. Researchers using matching methods often apply the bootstrap to calculate the standard errors. However, no formal justification has been provided for the use of the bootstrap in this setting. In this article, we show that the standard bootstrap is, in general, not valid for matching estimators, even in the simple case with a single continuous covariate where the estimator is root-N consistent and asymptotically normally distributed with zero asymptotic bias. Valid inferential methods in this setting are the analytic asymptotic variance estimator of Abadie and Imbens (2006a) as well as certain modifications of the standard bootstrap, like the subsampling methods in Politis and Romano (1994).
The production effects of agricultural income support policies under uncertainty

This analysis decomposes the production impacts of income support programs into wealth, insurance, and coupling effects. Under the usual assumptions about preferences, the wealth and insurance effects of many support programs increase optimal input levels even for supposedly decoupled programs. If the program is “coupled” in the usual sense, then all three effects often act in the same direction. It is concluded that studies of trade and domestic policy reform in stochastic environments should consider insurance and wealth effects. The derivative conditions required to obtain results are also subjected to scrutiny. Simulations for an Iowa corn producer confirm the comparative statics.
Large‐amplitude motion in polymer crystals and mesophases

Large-amplitude motion of macromolecules involves mainly rotation about bonds (conformational motion). In the liquid phases, the large-amplitude motion is coupled with disorder and accounts for the flow and viscoelastic behavior. Perfectly ordered crystals, in contrast, permit only little large-amplitude motion. The mesophases are intermediate in order and mobility. In crystals, large-amplitude motion leads initially to gauche defects and kinks (conformational defects), and ultimately may produce conformationally disordered crystals (condis crystals). Molecular dynamics simulations of crystals with up to 30 000 atoms have been carried out. They show the mechanism of defect formation, permit the study of the distribution of defects, and lead to a visualization of the hexagonal crystal phase. The main-chain liquid-crystalline macromolecules and condis crystals, the two mesophases of polymers, can be distinguished on the basis of an analysis of the phase separation (partial crystallinity), present in condis crystals and not in liquid crystals. Solid state NMR is the tool of choice for the detection of mobile and rigid phases. In highly drawn fibers one can find four different states of order and mobility. Besides the (defect) crystalline phase and the isotropic amorphous phase, an intermediate oriented phase and a rigid amorphous phase exist.
Every decision tree has an influential variable

We prove that for any decision tree calculating a Boolean function f : {-1,1}/sup n/ /spl rarr/ {-1, 1}, Var[f] /spl les/ /spl Sigma/ /sub i=1/ /sup n/ /spl delta//sup i/Inf/sub i/(f), i = 1 where /spl delta//sup i/ is the probability that the ith input variable is read and Inf/sub i/(f) is the influence of the ith variable on f. The variance, influence and probability are taken with respect to an arbitrary product measure on {-1, 1}/sup n/n. It follows that the minimum depth of a decision tree calculating a given balanced function is at least the reciprocal of the largest influence of any input variable. Likewise, any balanced Boolean function with a decision tree of depth d has a variable with influence at least 1/d. The only previous nontrivial lower bound known was /spl Omega/(d2/sup -d/). Our inequality has many generalizations, allowing us to prove influence lower bounds for randomized decision trees, decision trees on arbitrary product probability spaces, and decision trees with nonBoolean outputs. As an application of our results we give a very easy proof that the randomized query complexity of nontrivial monotone graph properties is at least/spl Omega/(v/sup 4/3//p/sup 1/3/), where v is the number of vertices and p /spl les/ 1/2 is the critical threshold probability. This supersedes the milestone /spl Omega/(v/sup 4/3//p/sup 1/3/) bound of Hajnal (1991) and is sometimes superior to the best known lower bounds of Chakrabarti-Khot (2001) and Friedgut-Kahn-Wigderson (2002).
Vinylcyclopropane Rearrangement of Ethyl 6-Ethenylbicyclo[3.1.0]hexane-1-acetate

Abstract The vinylcyclopropane (VCP) 2 was prepared by electrochemical reductive cyclization of β-dicarbonyl enol phosphate 1. The rearrangement of VCP 2 was investigated using a number of conditions including the use of a rhodium(I) complex, pyrolysis, treatment with cation radical source, and protic acid catalysis.
Short-?and long-range correlated motion observed in colloidal glasses and liquids

We use a confocal microscope to examine the motion of individual particles in a dense colloidal suspension. Close to the glass transition, particle motion is strongly spatially correlated. The correlations decay exponentially with particle separation, yielding a dynamic length scale of O(2?3?) (in terms of particle diameter ?). This length scale grows modestly as the glass transition is approached. Further, the correlated motion exhibits a strong spatial dependence on the pair correlation function g(r). Motion within glassy samples is weakly correlated, but with a larger spatial scale for this correlation.
State-space solution of the causal factorization problem

Given rational matrix functions, G, H, and R, a necessary and sufficient condition is given for the existence of a causal solution to the equation GXH=R. A formula is given for a solution of the equation when it exists, and this particular solution is used to parameterize the set of all causal solutions of the equation. The results are specialized to the case when the function G is identically equal to identity. Applications of the author's results include exact model matching and disturbance decoupling problems. >
The Economics of a Centralized Judiciary: Uniformity, Forum Shopping, and the Federal Circuit

Abstract In 1982, the U.S. Congress established the Court of Appeals for the Federal Circuit (CAFC) as the sole appellate court for patent cases. This court was created ostensibly to eliminate inconsistencies in the application and interpretation of patent law across federal courts and thereby mitigate the incentives of patentees and alleged infringers to forum shop for a preferred venue. We perform the first econometric study of the extent of nonuniformity and forum shopping in the pre‐CAFC era and of the CAFC’s impact on these phenomena. We find that in patentee‐plaintiff cases the pre‐CAFC era was indeed characterized by significant nonuniformity in patent validity rates across circuits and by forum shopping on the basis of validity rates. We find weak evidence that the CAFC has increased uniformity of validity rates and strong evidence that forum shopping on the basis of validity rates ceased several years prior to the CAFC’s establishment.
Information Processing Pattern and Propensity to Buy: An Investigation of Online Point-of-Purchase Behavior

The information processing literature provides a wealth of laboratory evidence on the effects that the choice task and individual characteristics have on the extent to which consumers engage in alternative-based versus attribute-based information processing. Less attention has been paid to studying how the processing pattern at the point of purchase is associated with a consumer's propensity to buy in shopping settings. To understand this relationship, we formulate a discrete choice model and perform formal model comparisons to distinguish among several possible dependence structures. We consider models involving an existing measure of information processing, PATTERN; a latent variable version of this measure; and several new refinements and generalizations. Analysis of a unique data set of 895 shoppers on a popular electronics website supports the latent variable specification and provides validation for several hypotheses and modeling components. We find a positive relationship between alternative-based processing and purchase, as well as a tendency of shoppers in the lower price category to engage in alternative-based processing. The results also support the case for joint modeling and estimation. These findings can be useful for future work in information processing and suggest that likely buyers can be identified while engaged in information processing prior to purchase commitment, an important first step in targeting decisions.
Ion extraction capabilities of two-grid accelerator systems

An experimental investigation into the ion extraction capabilities of two-grid accelerator systems common to electrostatic ion thrusters is described. This work resulted in a large body of experimental data which facilitates the selection of the accelerator system geometries and operating parameters necessary to maximize the extracted ion current. Results suggest that the impingement-limited perveance is not dramatically affected by reductions in screen hole diameter to 0.5 mm. Impingement-limited performance is shown to depend most strongly on grid separation distance, accelerator hole diameter ratio, the discharge-to-total accelerating voltage ratio, and the net-to-total accelerating voltage ratio. Results obtained at small grid separation ratios suggest a new grid operating condition where high beam current per hole levels are achieved at a specified net accelerating voltage. It is shown that this operating condition is realized at an optimum ratio of net-to-total accelerating voltage ratio which is typically quite high. The apparatus developed for this study is also shown to be well suited measuring the electron backstreaming and electrical breakdown characteristics of two-grid accelerator systems.
Simulation of Producer Gas Fired Power Plants with Inlet Fog Cooling and Steam Injection

Biomass can be converted to energy via direct combustion or thermo-chemical conversion to liquid or gas fuels. This study focuses on burning producer gases derived from gasifying biomass wastes to produce power. Since the producer gases are usually low calorific values (LCV), the power plants performance under various operating conditions has not yet been proven. In this study, system performance calculations are conducted for 5MWe power plants. The power plants considered include simple gas turbine systems, steam turbine systems, combined cycle systems, and steam injection gas turbine systems (STIG) using the producer gas with low calorific values at approximately 30% and 15% of the natural gas heating value (on a mass basis). The LCV fuels are shown to impose high back compressor pressure and produces increased power output due to increased fuel flow. Turbine nozzle throat area is adjusted to accommodate additional fuel flows to allow compressor operate within safety margin. The best performance occurs when the designed pressure ratio is maintained by widening nozzle openings, even though the TIT is reduced under this adjustment. Power augmentations under four different ambient conditions are calculated by employing gas turbine inlet fog cooling. Comparison between inlet fog cooling and steam injection using the same amount of water mass flow indicates that steam injection is less effective than inlet fog cooling in augmenting power output. Maximizing steam injection, at the expense of supplying the steam to the steam turbine, significantly reduces both the efficiency and the output power of the combined cycle. This study indicates that the performance of gas turbine and combined cycle systems fueled by the LCV fuels could be very different from the familiar behavior of natural gas fired systems. Care must be taken if onshelf gas turbines are modified to burn LCV fuels. NOMENCLATURE
THE CIRCUMSTELLAR MEDIUM OF CASSIOPEIA A INFERRED FROM THE OUTER EJECTA KNOT PROPERTIES

We investigate the effect of the circumstellar medium density profile on the X-ray emission from outer ejecta knots in the Cassiopeia A supernova remnant using the 1 Ms Chandra observation. The spectra of a number of radial series of ejecta knots at various positions around the remnant are analyzed using techniques similar to those devised in previous papers. We can obtain a reasonable match to our data for a circumstellar density profile proportional to r(sup -2) as would arise from the steady dense wind of a red supergiant, but the agreement is improved if we introduce a central cavity around the progenitor into our models. Such a profile might arise if the progenitor emitted a, fast tenuous stellar wind for a short period immediately prior to explosion. We review other lines of evidence supporting this conclusion. The spectra also indicate the widespread presence of Fe-enriched plasma that was presumably formed by complete Si burning during the explosion, possibly via alpha-rich freezeout. This component is typically associated with hotter and more highly ionized gas than the bulk of the O- and Si-rich ejecta.
An information-theoretic model for steganography

An information-theoretic model for steganography with a passive adversary is proposed. The adversary's task of distinguishing between an innocent cover message C and a modified message S containing hidden information is interpreted as a hypothesis testing problem. The security of a steganographic system is quantified in terms of the relative entropy (or discrimination) between the distributions of C and S, which yields bounds on the detection capability of any adversary. It is shown that secure steganographic schemes exist in this model provided the covertext distribution satisfies certain conditions. A universal stegosystem is presented in this model that needs no knowledge of the covertext distribution, except that it is generated from independently repeated experiments.
The Long-QT Syndrome

The heart is a pump that is stimulated by electrical signals to beat between about 50 to 180 times per minute, depending upon the individual’s level of activity and emotional state. The heart itself is made up of millions of cells that generate repetitive sequences of electrical discharges (referred to in medicine as depolarization) and recharging (repolarization) that produce each heart beat. Electrical activity of the heart cells is produced by the synchronized movement of sodium, potassium, and calcium ions into and out of the cells. ### Long-QT Syndrome Long-QT Syndrome (LQTS) is a disorder of the electrical activity of the heart that can result in blackouts (fainting, also known as syncope) or sudden cardiac death. It occurs infrequently and is caused either by an inherited genetic condition (inherited form of LQTS) or by some prescription medications (acquired form of LQTS). QT refers to the interval on ECG between the beginning of the heart’s electrical discharge through its electrical recovery (see Figure 1). Figure 1 illustrates how the QT interval is measured on the ECG. Schematic diagram of the electrical activity of one heart beat recorded by an ECG. The electrical discharge (depolarization) of the ventricle is represented by the QRS complex, with the T wave reflecting electrical recovery (repolarization). The QT is the time interval from the beginning of the QRS complex to the end of the T wave, and is generally less than 0.44 seconds in normal individuals. In subjects with the long-QT syndrome, the QT is usually longer than 0.44 seconds. Delayed electrical recovery within the heart can be associated with very dangerous, rapid, and chaotic heart rhythms (medical terms for these abnormal heart rhythms are …
Low-bias control of AMB subject to voltage saturation: state-feedback and observer designs

This paper addresses the problem of low-bias control for an active magnetic bearing (AMB) subject to voltage saturation. Using a generalized complementarity flux condition, a simple, three-dimensional (3-D) flux-based model is used to describe the dynamics of the low-bias mode of operation. Several stabilizing controllers are derived by applying recent results from nonlinear control theory. Specifically, the asymptotic small-gain theorem of Teel and passivity-based ideas are instrumental in our designs. Both soft and hard saturation constraints are accommodated. When flux measurements are not available, a nonlinear reduced order observer is proposed to estimate the flux. We show global asymptotic stability for all controller-observer interconnections. Numerical simulations against a high-fidelity AMB model show the effectiveness of the proposed control designs.
A software architecture for network communication

A communication abstraction called real-time message streams (RMS) is proposed. An RMS is a simplex (unidirectional) stream with several performance and security parameters that express the needs of RMS clients and the capabilities of the RMS provider. RMS providers can eliminate unnecessary or redundant work and can optimally schedule resources; RMS clients can use the parameters to select optimal methods for achieving reliability and flow control. RMS is the communication primitive of the DASH distributed system, which is currently being developed. The role of RMS in the DASH communication architecture and techniques and algorithms for providing RMS at different system levels are described. >
Synthesis and Spectroscopic Studies of Expanded Planar Dehydrotribenzo(n)annulenes Containing One or Two Isolated Alkene Units

Dehydrobenzoannulene derivatives containing isolated alkene linkages were synthesized by combining an in-situ Pd/Cu-mediated cross-coupling with an intramolecular cyclization strategy. 1H NMR studies of these macrocycles and comparison with related systems verify that highly alkynylated dehydrobenzoannulenes possess weak induced ring currents, indicative of aromatic (4n+2 π-systems) and anti-aromatic (4n π-systems) behavior, in spite of their large size and extensive benzannulation.
Election Surprises and Exchange Rate Uncertainty

This papers shows that unexpected election results explain some of the unexpected variation in foreign exchange rates. The result is based on an event study which examines the behavior of the size of forecast errors implied by futures contracts for exchange rates around elections. Though elections can produce large unexpected effects on exchange rates, the effects on forecast errors are short-lived. [ JEL codes: D72, F31.]
Complexity and life

During the last two decades, a new understanding of life emerged at the forefront of science.The development of complexity theory, technically known as nonlinear dynamics, has allowed scientists and mathematicians to model the complexities of living systems in new ways that have yielded many important discoveries. In this article, the author reviews the basic concepts, current achievements and status of complexity theory from the perspective of the new understanding of biological life. Models and theories discussed include the theory of dissipative structures for nonlinear chemical systems, the application of bifurcation theory to genetic networks and cell differentiation, the study of the origin of biological form (morphology), a new approach to the understanding of developmental stability in embryology, and a model of the ‘origin of life’ and prebiotic evolution in tiny, membrane-bounded vesicles in the primeval oceans.
Helical-Chiral Small Molecules in Asymmetric Catalysis

The design, synthesis and study of novel catalyst structures have had an enormous impact on asymmetric synthesis and continue to be a field of intense interest. Molecules with helical structures have fascinated chemists in the field for many years because such molecules are inherently chiral. A number of small molecules with such unique topology have been prepared in an optically active form and exploited as asymmetric catalysts. The story behind the development of these molecules is usually different in each case, in part due to differences in their synthetic accessibilities. This microreview provides some examples that illustrate the different ways in which such helical-chiral small molecules can be synthesized and used to catalyze reactions of interest, and highlights the beneficial effect of helical-chiral catalysts.
Asymmetric catalytic alkynylation of acetaldehyde: application to the synthesis of (+)-tetrahydropyrenophorol.

By controlling the kinetics of alkynylation over aldolisation (by slowing adding the acceptor), the challenging asymmetric catalytic alkynylation of acetaldehyde has been realized. This protocol yields the corresponding attractive synthons in good to excellent enantiocontrol and shows broad tolerance and applicability. This was highlighted by its application to the synthesis of several natural products such as the rapid construction of the macrocyclic diolide (+)-tetrahydropyrenophorol.
Fast Local Search for Unrooted Robinson-Foulds Supertrees

A Robinson-Foulds (RF) supertree for a collection of input trees is a tree containing all the species in the input trees that is at minimum total RF distance to the input trees. Thus, an RF supertree is consistent with the maximum number of splits in the input trees. Constructing RF supertrees for rooted and unrooted data is NP-hard. Nevertheless, effective local search heuristics have been developed for the restricted case where the input trees and the supertree are rooted. We describe new heuristics, based on the Edge Contract and Refine (ECR) operation, that remove this restriction, thereby expanding the utility of RF supertrees. Our experimental results on simulated and empirical data sets show that our unrooted local search algorithms yield better supertrees than those obtained from MRP and rooted RF heuristics in terms of total RF distance to the input trees and, for simulated data, in terms of RF distance to the true tree.
Facts and Figuring: An Experimental Investigation of Network Structure and Performance in Information and Solution Spaces

Using data from a novel laboratory experiment on complex problem solving in which we varied the structure of 16-person networks, we investigate how an organization's network structure shapes the performance of problem-solving tasks. Problem solving, we argue, involves both exploration for information and exploration for solutions. Our results show that network clustering has opposite effects for these two important and complementary forms of exploration. Dense clustering encourages members of a network to generate more diverse information but discourages them from generating diverse theories; that is, clustering promotes exploration in information space but decreases exploration in solution space. Previous research, generally focusing on only one of those two spaces at a time, has produced an inconsistent understanding of the value of network clustering. By adopting an experimental platform on which information was measured separately from solutions, we bring disparate results under a single theoretical roof and clarify the effects of network clustering on problem-solving behavior and performance. The finding both provides a sharper tool for structuring organizations for knowledge work and reveals challenges inherent in manipulating network structure to enhance performance, as the communication structure that helps one determinant of successful problem solving may harm the other.
Novel QCD Aspects of Hard Diffraction, Antishadowing, and Single-Spin Asymmetries

It is usually assumed--following the parton model--that the leading-twist structure functions measured in deep inelastic lepton-proton scattering are simply the probability distributions for finding quarks and gluons in the target nucleon. In fact, gluon exchange between the outgoing quarks and the target spectators effects the leading-twist structure functions in a profound way, leading to diffractive leptoproduction processes, shadowing and antishadowing of nuclear structure functions, and target spin asymmetries, physics not incorporated in the light-front wavefunctions of the target computed in isolation. In particular, final-state interactions from gluon exchange lead to single-spin asymmetries in semi-inclusive deep inelastic lepton-proton scattering which are not power-law suppressed in the Bjorken limit. The shadowing and antishadowing of nuclear structure functions in the Gribov-Glauber picture is due respectively to the destructive and constructive interference of amplitudes arising from the multiple-scattering of quarks in the nucleus. The effective quark-nucleon scattering amplitude includes Pomeron and Odderon contributions from multi-gluon exchange as well as Reggeon quark-exchange contributions. Part of the anomalous NuTeV result for sin{sup 2} {theta}{sub W} could be due to the non-universality of nuclear antishadowing for charged and neutral currents. Detailed measurements of the nuclear dependence of individual quark structure functions are thus needed to establish themore » distinctive phenomenology of shadowing and antishadowing and to make the NuTeV results definitive. I also discuss diffraction dissociation as a tool for resolving hadron substructure Fock state by Fock state and for producing leading heavy quark systems.« less
Regression with missing Ys: An improved strategy for analyzing multiply imputed data

When fitting a generalized linear model—such as linear regression, logistic regression, or hierarchical linear modeling—analysts often wonder how to handle missing values of the dependent variable Y. If missing values have been filled in using multiple imputation, the usual advice is to use the imputed Y values in analysis. We show, however, that using imputed Ys can add needless noise to the estimates. Better estimates can usually be obtained using a modified strategy that we call multiple imputation, then deletion (MID). Under MID, all cases are used for imputation but, following imputation, cases with imputed Y values are excluded from the analysis. When there is something wrong with the imputed Y values, MID protects the estimates from the problematic imputations. And when the imputed Y values are acceptable, MID usually offers somewhat more efficient estimates than an ordinary MI strategy.
On the Galactic distribution of gamma-ray bursts

Quashnock & Lamb (hereafter QL) have recently defined a subsample of gamma-ray bursts (GRBs) from the publicly available BATSE data base that shows clumping toward the Galactic plane, and they conclude that all GRBs are Galactic in origin. The selection of these bursts (duplicated in this work in sample 1) involved a peak count rate [in count (1024 ms) −1 ] that is uncorrected for aspect. Using, as limits, the corresponding peak fluxes (in photon cm −2 s −1 ) for the bursts in the QL sample, we find an additional 24 bursts, which we include in a new sample (sample 2). We assert that the peak flux of a burst - the peak count rate corrected for detector aspect and energy response - is physically more meaningful than the peak count rate as used by QL
NUMERICAL SIMULATION METHODS OF INCOMPRESSIBLE FLOWS AND AN APPLICATION TO THE SPACE SHUTTLE MAIN ENGINE

This paper discusses incompressible Navier-Stokes solution methods with an emphasis on the pseudocompressibility method. A steady-state flow solver based on the pseudocompressibility approach is then described. This flow solver code has been used to analyze the internal flow in the Space Shuttle main engine hot-gas manifold. Salient features associated with this three-dimensional realistic flow simulation are discussed. Numerical solutions relevant to the current engine analysis and the redesign effort are discussed along with experimental results. This example demonstrates the potential of computational fluid dynamics as a design tool for aerospace applications.
A 24-bit delta—sigma ADC with an ultra-low noise chopper-stabilized programmable gain instrumentation amplifier

Abstract A 24-bit delta–sigma analog-to-digital converter with a programmable gain amplifier is presented. The converter uses a dual amplifier input structure to optimize it for different measurement tasks. One of the amplifiers is a chopper-stabilized multipath feedforward architecture that achieves exceptionally high open loop gain with very low drift and ultra-low noise.
Information gaps: myth or reality?

Abstract The rising importance of information technologies is said to threaten ever wider gaps between groups in society. This article considers to what extent the warning are valid. The author traces the history of the introduction in the USA of the telephone, electricity and other innovations and finds that all have followed the same pattern — access was limited in the early stages. He concludes that there is no need to act precipitously to improve access to information technologies and, in any case, the type of action needed is not at all obvious. As the world's work force becomes wealthier and technology costs decline, the differences in all aspects of living standards will decrease.
FEL performance with pure permanent-magnet undulators having optimized ordering

Abstract The degradation of FEL performance by field errors can be greatly mitigated in a pure permanent-magnet undulator by appropriate ordering of magnets. Monte Carlo techniques have been used to obtain such optimized ordering for various systems. The resulting performance improvement has been evaluated using the Rocketdyne simulation code FELOPT.
When Sunlight Fails to Disinfect: Understanding the Perverse Effects of Disclosing Conflicts of Interest

Disclosure is often proposed as a remedy for conflicts of interest, but it can backfire, hurting those whom it is intended to protect. Building on our prior research, we introduce a conceptual model of disclosure’s effects on advisors and advice recipients that helps to explain when and why it backfires. Studies 1 and 2 examine psychological mechanisms (strategic exaggeration, moral licensing) by which disclosure can lead advisors to give more-biased advice. Study 3 shows that disclosure backfires when advice recipients who receive disclosure fail to sufficiently discount and thus fail to mitigate the adverse effects of disclosure on advisor bias. Study 4 identifies one remedy for inadequate discounting of biased advice: explicitly and simultaneously contrasting biased advice with unbiased advice.
Commercial Real Estate Market Property Level Capital Expenditures: An Options Analysis

Option pricing theory predicts that capital improvement expenditures are positively linked with high or increasing market lease rates. Ceteris paribus, when the market lease rate is high, or when there is an expectation of higher lease rates in the future, owners are encouraged to increase investment to capture a larger profit. In contrast, when the market lease rate is low, or when there is an expectation of lower lease rates in the future, owners are encouraged to defer capital improvements, causing a skewness in the cash flows. Our empirical results generally support the notion that normal levels of capital expenditures not only maintain value but also actually may create value.
Monetary Policy and the Redistribution Channel

This paper evaluates the role of redistribution in the transmission mechanism of monetary policy to consumption. Using consumer theory, I show that redistribution has aggregate effects whenever marginal propensities to consume (MPCs) covary, across households, with balancesheet exposures to aggregate shocks. Unexpected inflation gives rise to a Fisher channel and real interest rate shocks to an interest rate exposure channel; both channels are likely to contribute to the expansionary effects of accommodative monetary policy. Indeed, using a sufficient statistic approach, I find that redistribution could be the dominant reason why aggregate consumer spending reacts to transitory changes in the real interest rate, provided households’ elasticities of intertemporal substitution are reasonably small (0.3 or less in the United States). I then build and calibrate a general equilibrium model with heterogeneity in MPCs, and I evaluate how the redistribution channel alters the economy’s response to shocks. When household assets and liabilities have short effective maturities, the interest rate exposure channel raises the elasticity of aggregate demand to real interest rates, which dampens fluctuations in the natural rate of interest in response to exogenous shocks and amplifies the real effects of monetary policy shocks. The model predicts that if U.S. mortgages all had adjustable rates—as they do in the U.K.—the effect of interest-rate changes on consumer spending would more than double. In addition, this effect would be asymmetric, with rate increases reducing spending by more than cuts would increase it.
Deep temporal sigmoid belief networks for sequence modeling

Deep dynamic generative models are developed to learn sequential dependencies in time-series data. The multi-layered model is designed by constructing a hierarchy of temporal sigmoid belief networks (TSBNs), defined as a sequential stack of sigmoid belief networks (SBNs). Each SBN has a contextual hidden state, inherited from the previous SBNs in the sequence, and is used to regulate its hidden bias. Scalable learning and inference algorithms are derived by introducing a recognition model that yields fast sampling from the variational posterior. This recognition model is trained jointly with the generative model, by maximizing its variational lower bound on the log-likelihood. Experimental results on bouncing balls, polyphonic music, motion capture, and text streams show that the proposed approach achieves state-of-the-art predictive performance, and has the capacity to synthesize various sequences.
Polymorphism in Br2 clathrate hydrates.

The structure and composition of bromine clathrate hydrate has been controversial for more than 170 years due to the large variation of its observed stoichiometries. Several different crystal structures were proposed before 1997 when Udachin et al. (Udachin, K. A.; Enright, G. D.; Ratcliffe, C. I.; Ripmeester, J. A. J. Am. Chem. Soc. 1997, 119, 11481) concluded that Br2 forms only the tetragonal structure (TS-I). We show polymorphism in Br2 clathrate hydrates by identifying two distinct crystal structures through optical microscopy and resonant Raman spectroscopy on single crystals. After growing TS-I crystals from a liquid bromine−water solution, upon dropping the temperature slightly below −7 °C, new crystals of cubic morphology form. The new crystals, which have a limited thermal stability range, are assigned to the CS-II structure. The two structures are clearly distinguished by the resonant Raman spectra of the enclathrated Br2, which show long overtone progressions and allow the extraction of accura...
Naturalized Epistemology and the Critique of Evidence Theory

In this article I give a mixed review Allen and Leiter’s naturalized epistemology theory of evidence. I applaud their focus on naturalized epistemology, but I question the claims that they argue follow from it. In some ways, my reaction is that they have not gone far enough in pressing its implications, and I attempt to suggest how further progress might be made along this path. On the whole, I conclude that the antipathy toward algorithms expressed by Allen and Leiter is misplaced.
Defining Terrorism as the Peacetime Equivalent of War Crimes: Problems and Prospects

This article examines the proposal to define terrorism as the peacetime equivalent of war crimes in the context of answering two questions: First, why might it be useful to define terrorism by reference to the existing laws of war? And second, what are the potential negative consequences which might counsel against such an approach?
Genetic optimization and experimental validation of a test cycle that maximizes parameter identifiability for a Li-ion equivalent-circuit battery model

Abstract This article presents an experimental study demonstrating the degree to which optimal experimental design can improve lithium-ion battery parameter estimation. The article is motivated by previous literature showing that lithium-ion batteries suffer from poor parameter identifiability. This makes it difficult to estimate battery parameters quickly and accurately from input–output cycling data. Previous research shows that optimizing the shape of a battery cycle for Fisher information – an identifiability metric – can improve parameter estimation speed and accuracy significantly. However, most studies demonstrating this improvement are simulation-based, rather than experimental. In contrast, the centermost goal in this article is to provide an experimental assessment of the degree to which trajectory optimization for Fisher identifiability can improve lithium-ion battery parameter estimation. We optimize battery cycling to maximize Fisher information for a nonlinear second-order model of a commercial lithium iron phosphate (LFP) cell. We implement this optimal cycle experimentally for 3 different battery cells, and compare it with two benchmark cycles representing automotive battery use. The results of this comparison are quite compelling: when parameterized using data from the optimal cycle, the cell voltage prediction signal-to-noise ratio improves significantly over the benchmarks. Moreover, only the optimized cycle produces reasonable estimates of battery parameters over the course of a 4-hour experiment.
Cluster Functions and Scattering Amplitudes for Six and Seven Points

Scattering amplitudes in planar super-Yang-Mills theory satisfy several basic physical and mathematical constraints, including physical constraints on their branch cut structure and various empirically discovered connections to the mathematics of cluster algebras. The power of the bootstrap program for amplitudes is inversely proportional to the size of the intersection between these physical and mathematical constraints: ideally we would like a list of constraints which determine scattering amplitudes uniquely. We explore this intersection quantitatively for two-loop six- and seven-point amplitudes by providing a complete taxonomy of the Gr(4, 6) and Gr(4, 7) cluster polylogarithm functions of [15] at weight 4.
An infrared study of the behavior of CO, NO, and CO + NO over Rh/Al2O3 catalysts

Infrared spectroscopy was used to study the interaction of carbon monoxide and nitric oxide on a 0.475% RhAl2O3 catalyst. Both CO and NO readily adsorb on a prereduced catalyst surface. NO is not observed spectroscopically on preoxidized catalysts, yet isocyanate is produced during subsequent displacement by CO. The adsorption of CO on a preoxidized catalyst parallels the reduction of the catalyst. At temperatures in excess of 250 °C and mixed feeds with CONO ≥ 1, a large buildup of isocyanate is observed on the support. At temperatures greater than 300 °C an infrared band attributed to adsorbed cyanide ion is observed near 2150 cm−1. Experiments involving displacement of NO by CO, displacement of CO by NO, and coadsorption of CO + NO show that contiguous rhodium surfaces are necessary for isocyanate production. Though the rhodium gem-dicarbonyl species, Rh(CO)2, was observed, there was no experimental evidence demonstrating the presence of Rh(NO)2 or Rh(NO)(CO) complexes.
Efficient Sovereign Default

In this article, I show that the key aspects of sovereign debt crises can be rationalized as part of the efficient risk-sharing arrangement between a sovereign borrower and foreign lenders in a production economy with informational and commitment frictions. The constrained efficient allocation involves ex post inefficient outcomes that resemble sovereign default episodes in the data and can be implemented with non-contingent defaultable bonds and active maturity management. Defaults and periods of temporary exclusion from international credit markets happen along the equilibrium path and are essential to supporting the efficient allocation. Furthermore, during debt crises, the maturity composition of debt shifts towards short-term debt and the term premium inverts as in the data.
Families and Springer’s correspondence

We establish a relation between the known parametrization of a family of irreducible representations of a Weyl group and Springer's correspondence. We outline a parametrization of unipotent character sheaves on a connected reductive group in terms of restrictions to various conjugacy classes.
A Serendipitous Synthesis of Bis-Heterocyclic Spiro 3(2H)-Furanones

(Z) Enol triflates 6, 11b–d, (E) enol triflate 11e, and phenol triflate 11a, derived from β-keto esters or 2-carboalkoxy phenols, respectively, react with N-Boc 2-lithiopyrrolidine (5a), N-Boc N-methylaminomethyllithium (5b), or 2-lithio-1,3-dithiane (14) to afford 3(2H)-furanones in modest to good yields (38–81%). Product and carbanion reagent studies suggest that the 3(2H)-furanone is formed in a cascade of reactions involving nucleophilic acyl substitution, enolate formation, trifluoromethyl transfer, iminium or sulfenium ion formation, and subsequent ring closure to form the 3(2H)-furanone. The use of 2-lithio-1,3-dithiane affords a cyclic α-keto-S,S,O-orthoester in which the functionality can be selectively manipulated for synthetic applications.
Entry, Exit, and Investment-Specific Technical Change

Using European data, this paper finds that (i) industry entry and exit rates are positively related to industry rates of investment-specific technical change (ISTC); and (ii) the sensitivity of industry entry and exit rates to cross-country differences in entry costs depends on industry rates of ISTC. The paper con structs a general equilibrium model in which the rate of ISTC varies across industries and new investment-specific technologies can be introduced by entrants or by incumbents. In the calibrated model, equilibrium behavior is consistent with stylized facts (i) and (ii), provided the cost of technology adop tion is increasing in the rate of ISTC. (JEL G31, LI 1, 031, 033) Entry and exit rates differ significantly across industries. Over the period 1963-1982, Timothy Dunne, Mark J. Roberts, and Larry Samuelson (1988) find that five-year entry rates in US manu facturing data range from 21 percent in tobacco to 60 percent in scientific instruments. High entry industries are high-exit industries, suggesting that entry and exit are largely due to the same industry-specific factors. At the same time, little is known about what these factors might be. This paper finds a strong, positive link between industry entry and exit rates and the pace of technical progress in the capital goods that the industry uses?the rate of investment-specific technical change (ISTC). A significant fraction of entry and exit thus represents the introduction and replacement of capital-embodied technologies. ISTC is also positively related to the proportion of enterprises in each industry that displays large investment outlays in a given year. That investment often occurs in "spikes" has been known since at least Mark Doms and Dunne (1998), and the results link this pattern to the replacement of new capital-embodied technologies by incumbents. Furthermore, the decision of whether (or when) to exit appears sensitive to policy: in countries in which the cost of entry is high, rates of entry and exit are disproportionately suppressed in industries with high rates of ISTC. To analyze these findings, the paper develops a general equilibrium model in which chang ing the vintage of capital used by a particular enterprise is costly. In the model, this vintage is termed a "technology" and an enterprise is a technology-manager pair. The manager accumu lates expertise with a given technology over time, and at any date may choose to upgrade to a newer technology?at the expense of accumulated expertise, as in Boyan Jovanovic and Yaw
Estimating a Semi-Parametric Duration Model without Specifying Heterogeneity

This paper presents a new estimator for the mixed proportional hazard model that allows for a nonparametric baseline hazard and time-varying regressors. In particular, this paper allows for discrete measurement of the durations as happens often in practice. The integrated baseline hazard and all parameters are estimated at regular rate, √ N, where N is the number of individuals. A hazard model is a natural framework for time-varying regressors if a flow or a transition probability depends on a regressor that changes with time since a hazard model avoids the curse of dimensionality that would arise from interacting the regressors at each point in time with one another.
Metallic Borides, La2Re3B7 and La3Re2B5, Featuring Extensive Boron–Boron Bonding

La2Re3B7 and La3Re2B5 have been synthesized in single-crystalline form from a molten La/Ni eutectic at 1000 °C in the first example of the flux crystal growth of ternary rare-earth rhenium borides. Both compounds crystallize in their own orthorhombic structure types, with La2Re3B7 (space group Pcca) having lattice parameters a = 7.657(2) A, b = 6.755(1) A, and c = 11.617(2) A, and La3Re2B5 (space group Pmma) having lattice parameters a = 10.809(2) A, b = 5.287(1) A, and c = 5.747(1) A. The compounds possess three-dimensional framework structures that are built up from rhenium boride polyhedra and boron–boron bonding. La3Re2B5 features fairly common B2 dumbbells, whereas La2Re3B7 has unique one-dimensional subunits composed of alternating triangular B3 and trans-B4 zigzag chain fragments. Also observed in La3Re2B5 is an unusual coordination of B by an octahedron of La atoms. Electronic band structure calculations predict that La2Re3B7 is a semimetal, which is observed in the electrical resistivity data as ...
Why the english-speaking world needs confucius institutes

Advantages of speaking English as a native speaker have been discussed and debated widely. English has developed into a global lingua franca in business, culture, education and diplomacy. English “demand” includes institutional demands and individual demands for language to achieve better employment and enjoy English-language goods. Supply can be seen in these English-language goods, the use of English in institutional settings, the robustness of this language, and an increasing supply of English speakers through learning English as a second language. But within the dynamics of this development lie the seeds of a disadvantage for native English speakers. As the educated world learns English, personal advantage may shift away from the native English speaker toward those speaking English plus other languages. Given lower levels of foreign language-learning in the Anglophone world and increasing numbers of multilingual non-native English speakers, native English speakers may see their advantage disappear. Integrating international business and trade theory with sociolinguistics and language economics this paper argues that native English speakers will face a disadvantage in twenty firsts century due to their English dependency and Confucius Institutes may help young native English speakers overcome this emerging disadvantage.