cssi/SciSciGPT-SciSciNet huggingface dataset:
Reciprocity-induced symmetry in the round-trip transmission through complex systems

Reciprocity is a fundamental principle of wave physics and directly relates to the symmetry in the transmission through a system when interchanging the input and output. The coherent transmission matrix (TM) is a convenient method to characterize wave transmission through general media. Here, we demonstrate the optical reciprocal nature of complex media by exploring their TM properties. We measured phase-corrected TMs of forward and round-trip propagation in a single polarization state through a looped 1 m-long step-index optical multimode fiber (MMF) to experimentally verify a transpose relationship between the forward and backward transmission. This symmetry impedes straightforward MMF calibration from proximal measurements of the round-trip TM. Furthermore, we show how focusing through the MMF with digital optical phase conjugation is compromised by system loss since time reversibility relies on power conservation. These insights may inform the development of new imaging techniques through complex media and coherent control of waves in photonic systems.
Islands in cosmology

A quantum extremal island suggests that a region of spacetime is encoded in the quantum state of another system, like the encoding of the black hole interior in Hawking radiation. We study conditions for islands to appear in general spacetimes, with or without black holes. They must violate Bekenstein’s area bound in a precise sense, and the boundary of an island must satisfy several other information-theoretic inequalities. These conditions combine to impose very strong restrictions, which we apply to cosmological models. We find several examples of islands in crunching universes. In particular, in the four-dimensional FRW cosmology with radiation and a negative cosmological constant, there is an island near the turning point when the geometry begins to recollapse. In a two-dimensional model of JT gravity in de Sitter spacetime, there are islands inside crunches that are encoded at future infinity or inside bubbles of Minkowski spacetime. Finally, we discuss simple tensor network toy models for islands in cosmology and black holes.
Self-Interacting Dark Matter with Naturally Light Mediator

A promising proposal for resolving the cusp–core anomaly in the density profile of dwarf galaxies is to allow dark matter to interact with itself through a light mediator of mass much less than a GeV. The theoretical challenge is to have a complete renormalizable theory where this happens naturally even though dark matter itself may be of the electroweak scale, i.e. 100 GeV to 1 TeV. I propose here such a model with just two neutral complex scalar singlets under a softly broken dark global U(1) symmetry.
Whimper of a Bang: Documenting the Final Days of the Nearby Type Ia Supernova 2011fe

Using the Hubble Space Telescope (HST) and the Large Binocular Telescope, we followed the evolution of the Type Ia supernova (SN Ia) 2011fe for an unprecedented 1840 days past $B$-band maximum light and over a factor of $7$ million in flux. At 1840 days, the 4000 - 17000 A quasi-bolometric luminosity is just ($420 \pm 20$) $L_{\odot}$. By measuring the late-time quasi-bolometric light curve, we present the first confident detection of $^{57}$Co decay in a SN Ia light curve and estimate a mass ratio of $\log (^{57}\mathrm{Co}/^{56}\mathrm{Co}) = -1.59^{+ 0.06 }_{- 0.07 }$. We do not have a clean detection of $^{55}\mathrm{Fe}$, but find a limit of $^{55}\mathrm{Fe}/^{57}\mathrm{Co} < 0.22$ with 99% confidence. These abundance ratios provide unique constraints on the progenitor system because the central density of the exploding white dwarf(s) dictates these nucleosynthetic yields. The observed ratios strongly prefer the lower central densities of double-degenerate models ($^{55}\mathrm{Fe}/^{57}\mathrm{Co} = 0.27$) over the higher central densities of near-Chandrasekhar-mass single-degenerate models ($^{55}\mathrm{Fe}/^{57}\mathrm{Co} = 0.68$). However, additional theoretical studies predicting isotopic yields from a broader range of progenitor systems are motivated by these unique observations. We will continue to observe SN 2011fe for another $\sim 600$ days with HST and possibly beyond.
Cryo-EM structure of the calcium release-activated calcium channel Orai in an open conformation.

The calcium release-activated calcium channel Orai regulates Ca2+ entry into non-excitable cells and is required for proper immune function. While the channel typically opens following Ca2+ release from the endoplasmic reticulum, certain pathologic mutations render the channel constitutively open. Previously, using one such mutation (H206A), we obtained low (6.7 A) resolution X-ray structural information on Drosophila melanogaster Orai in an open conformation (Hou et al., 2018). Here we present a structure of this open conformation at 3.3 A resolution using fiducial-assisted cryo-electron microscopy. The improved structure reveals the conformations of amino acids in the open pore, which dilates by outward movements of subunits. A ring of phenylalanine residues repositions to expose previously shielded glycine residues to the pore without significant rotational movement of the associated helices. Together with other hydrophobic amino acids, the phenylalanines act as the channel's gate. Structured M1-M2 turrets, not evident previously, form the channel's extracellular entrance.
Implementation of Outpatient Minimally Invasive Lumbar Decompression at an Academic Medical Center without Ambulatory Surgery Centers: A Cost Analysis and Systematic Review.

Background Lumbar decompressions are increasingly performed at ambulatory surgery centers (ASCs). We sought to compare costs of open and minimally invasive (MIS) lumbar decompressions performed at a university without dedicated ASCs. Methods Lumbar decompressions performed at a tertiary academic hospital or satellite university hospital dedicated to outpatient surgery were retrospectively reviewed. Care pathways were same-day, overnight observation, or inpatient admission. Patient demographics, American Society of Anesthesiologists classification, Charlson Comorbidity Index, surgical characteristics, 30-day readmission, and costs were collected. A systematic review of lumbar decompression cost literature was performed. Results A total of 354 patients, mean age 55 years with 128 women (36.2%), were reviewed. There was no significant difference in age, gender, body mass index, American Society of Anesthesiologists classification, or Charlson Comorbidity Index between patients treated with open and minimally invasive surgery. Open decompression was associated with higher total cost ($21,280 vs. $14,407; P Conclusions When accounting for care pathway, the cost of open and MIS decompression were no different. Transition from a tertiary academic hospital to a university hospital specializing in outpatient surgery was not associated with lower costs. Academic departments may consider transitioning lumbar decompressions to a dedicated ASC to maximize cost savings; however, additional studies are needed.
Coexistence of phases and interphase boundaries in BaTiO3

A theoretical analysis of the internal structure of interphase boundaries separating domains of coexisting phases is presented for the perovskite ferroelectric BaTiO3. The temperature dependence of...
Naive-Student: Leveraging semi-supervised learning in video sequences for urban scene segmentation

Supervised learning in large discriminative models is a mainstay for modern computer vision. Such an approach necessitates investing in large-scale human-annotated datasets for achieving state-of-the-art results. In turn, the efficacy of supervised learning may be limited by the size of the human annotated dataset. This limitation is particularly notable for image segmentation tasks, where the expense of human annotation is especially large, yet large amounts of unlabeled data may exist. In this work, we ask if we may leverage semi-supervised learning in unlabeled video sequences and extra images to improve the performance on urban scene segmentation, simultaneously tackling semantic, instance, and panoptic segmentation. The goal of this work is to avoid the construction of sophisticated, learned architectures specific to label propagation (e.g., patch matching and optical flow). Instead, we simply predict pseudo-labels for the unlabeled data and train subsequent models with both human-annotated and pseudo-labeled data. The procedure is iterated for several times. As a result, our Naive-Student model, trained with such simple yet effective iterative semi-supervised learning, attains state-of-the-art results at all three Cityscapes benchmarks, reaching the performance of 67.8% PQ, 42.6% AP, and 85.2% mIOU on the test set. We view this work as a notable step towards building a simple procedure to harness unlabeled video sequences and extra images to surpass state-of-the-art performance on core computer vision tasks.
A nanobody suite for yeast scaffold nucleoporins provides details of the nuclear pore complex structure

Nuclear pore complexes (NPCs) are the main conduits for molecular exchange across the nuclear envelope. The NPC is a modular assembly of ~500 individual proteins, called nucleoporins or nups. Most scaffolding nups are organized in two multimeric subcomplexes, the Nup84 or Y complex and the Nic96 or inner ring complex. Working in S. cerevisiae, and to study the assembly of these two essential subcomplexes, we here develop a set of twelve nanobodies that recognize seven constituent nucleoporins of the Y and Nic96 complexes. These nanobodies all bind specifically and with high affinity. We present structures of several nup-nanobody complexes, revealing their binding sites. Additionally, constitutive expression of the nanobody suite in S. cerevisiae detect accessible and obstructed surfaces of the Y complex and Nic96 within the NPC. Overall, this suite of nanobodies provides a unique and versatile toolkit for the study of the NPC.
What Does This Acronym Mean? Introducing a New Dataset for Acronym Identification and Disambiguation

Acronyms are the short forms of phrases that facilitate conveying lengthy sentences in documents and serve as one of the mainstays of writing. Due to their importance, identifying acronyms and corresponding phrases (i.e., acronym identification (AI)) and finding the correct meaning of each acronym (i.e., acronym disambiguation (AD)) are crucial for text understanding. Despite the recent progress on this task, there are some limitations in the existing datasets which hinder further improvement. More specifically, limited size of manually annotated AI datasets or noises in the automatically created acronym identification datasets obstruct designing advanced high-performing acronym identification models. Moreover, the existing datasets are mostly limited to the medical domain and ignore other domains. In order to address these two limitations, we first create a manually annotated large AI dataset for scientific domain. This dataset contains 17,506 sentences which is substantially larger than previous scientific AI datasets. Next, we prepare an AD dataset for scientific domain with 62,441 samples which is significantly larger than previous scientific AD dataset. Our experiments show that the existing state-of-the-art models fall far behind human-level performance on both datasets proposed by this work. In addition, we propose a new deep learning model which utilizes the syntactical structure of the sentence to expand an ambiguous acronym in a sentence. The proposed model outperforms the state-of-the-art models on the new AD dataset, providing a strong baseline for future research on this dataset.
A strategic pricing framework

Presents a strategic pricing framework which conceptualizes pricing outcomes or objectives as a function of pricing strategies constrained by environmental factors. Offers marketers a model to explain and enhance price decision making. Notes that as long as firms adhere to a strict policy regarding margins, they can be sure that prices are in line.
Information Disclosure and Network Formation in News Subscription Services

We study the formation of a subscription network where a continuum of strategic, Bayesian subscribers decide to subscribe to one of two sources (leaders) for news that is informative about an underlying state of the world. The leaders, aiming to maximize the welfare of all subscribers, have a motive to persuade the subscribers to take the optimal binary action against the state according to their own perspectives. With this persuasion motive, each leader decides whether to disclose the news to her own subscribers when there is news. When the subscribers receive the news, they update their beliefs; more importantly, even when no news is disclosed, the subscribers update their beliefs, speculating that there may be news that was concealed due to the leader’s strategic disclosure decision. We prove that at any equilibrium, the set of news signals that are concealed by the leaders takes the form of an interval. We further show that when two leaders represent polarized and opposing perspectives, anti-homophily emerges among the subscribers whose perspectives are in the middle. For any subscriber with a perspective on the extremes, and for any leader, there exists an equilibrium at which the subscriber would follow the leader. Our results shed light on how individuals would seek information when information is private or costly to obtain, while considering the strategic disclosure by the news providers who are partisan and have a hidden motive to persuade their followers.
On Growth of Generalized Grigorchuk's Overgroups

Grigorchuk's Overgroup \(\widetilde{\mathcal{G}}\), is a branch group of intermediate growth. It contains the first Grigorchuk's torsion group \(\mathcal{G}\) of intermediate growth constructed in 1980, but also has elements of infinite order. Its growth is substantially greater than the growth of \(\mathcal{G}\). The group \(\mathcal{G}\), corresponding to the sequence \((012)^\infty = 012012 \dots\), is a member of the family \(\{ G_\omega | \omega \in \Omega = \{ 0, 1, 2 \}^\mathbb{N} \}\) consisting of groups of intermediate growth when sequence \(\omega\) is not eventually constant. Following this construction we define the family \(\{ \widetilde{G}_\omega, \omega \in \Omega \}\) of generalized overgroups. Then \(\widetilde{\mathcal{G}} = \widetilde{G}_{(012)^\infty}\) and \(G_\omega\) is a subgroup of \(\widetilde{G}_\omega\) for each \(\omega \in \Omega\). We prove, if \(\omega\) is eventually constant, then \(\widetilde{G}_\omega\) is of polynomial growth and if \(\omega\) is not eventually constant, then \(\widetilde{G}_\omega\) is of intermediate growth.
Statistics of Robust Optimization: A Generalized Empirical Likelihood Approach

We study statistical inference and distributionally robust solution methods for stochastic optimization problems, focusing on confidence intervals for optimal values and solutions that achieve exac...
Investor protection and analysts’ cash flow forecasts around the world

We find that analysts are more likely to provide cash flow forecasts in countries with weak investor protection. This finding is consistent with our hypothesis that market participants demand (and analysts supply) cash flow information when weak investor protection results in earnings that are less likely to reflect underlying economic performance. Our results suggest that information intermediaries respond to market-based incentives to attenuate the adverse effects of country-level institutional factors on earnings’ usefulness. These findings contribute to the literature by shedding light on the institutional determinants of analysts’ research activities, and on the nature of the financial information they generate.
The effect of Wal-Mart Supercenters on grocery prices in New england

This study examines the competitive price effect of Wal-Mart Supercenters on national brand and private label grocery prices in New England. For this purpose, we use primary price data collected on a basket of identical products from six Supercenters in Massachusetts, Connecticut, and Rhode Island as well as a sample of conventional supermarkets. Taking into account demographics, store characteristics, and market conditions, we estimate the average prices charged by (1) Supercenters, (2) supermarkets competing directly with Supercenters, and by (3) supermarkets geographically distant from Supercenters. By comparing prices at competing stores and at distant stores, we show that the effect of Wal-Mart Supercenters is to decrease prices by 6 to 7 percent for national brand goods and 3 to 7 percent for private label goods. Price decreases are most significant in the dry grocery and dairy departments. Moreover, WalMart sets prices significantly lower than its competitors in the food industry.
The Elusive Quest for Convergence

Does American political representation work as predicted by theory? On average, political candidates diverge considerably in their ideological positioning, but do they diverge less on issues of particular salience to their local constituents? We combine data on congressional roll call votes, electoral outcomes, district demographics, and substantive information about bills to search for convergence in the places we would most expect to find it. Despite the predictions of prominent models, legislators diverge just as much even when their constituents have strong interests in a particular policy area. These results provide new insights into policymaking and political representation, and they help distinguish between different theoretical explanations for why candidate positions diverge.
Life away from work

A number of states assure employees the right to consume a lawful product on their own time and off the employer's premises, and a very few states protect an employee's right to engage in all lawful activities away from work. These laws have recently been attacked as having no basis in public interest, as substituting a judicial for an employer's judgment of what serves business need - a decision the courts are ill-suited to make - and for eroding the at-will rule. This essay, given at a conference sponsored by the Louisiana Law Review on February 9-10, 2006, replies to that critique. It grounds these laws in the public interest; it explores the consequences of juridification of off-duty life by examination of decisions in France and Germany where such is protected; and, it argues that there is no reason why U.S. employees should not enjoy the same right to a life away from work as do their European counterparts.
$2.00 Gas! Studying the effects of a gas tax moratorium ☆

There are surprisingly few estimates of the effects of sales taxes on retail prices, especially at the firm level. We consider the temporary suspension, and subsequent reinstatement, of the gasoline sales tax in Illinois and Indiana following a price spike in 2000. Earlier laws set the timing of the reinstatements, providing plausibly exogenous changes in the tax rates. Using a unique dataset of daily prices at the gas-station level, 70% of the tax suspension is passed on to consumers in the form of lower prices, while 80–100% of the tax reinstatements are passed on to consumers. Some evidence suggests that these short-run pass-through estimates are smaller near the state borders, with the tax reinstatements associated with relatively higher prices up to an hour's drive into neighboring states.
A model of trust building with anonymous re-matching

Abstract This paper studies a repeated lender-borrower game with anonymous re-matching (that is, once an ongoing relationship is terminated, players are rematched with new partners and prior histories are unobservable). We propose an equilibrium refinement based on two assumptions: (a) default implies termination of the current relationship; (b) in a given relationship, a better loan-repayment history implies weakly higher continuation values for both parties. This refinement captures the idea of “justifiable punishments” in repeated games. We show that if agents are patient enough and re-matching is sufficiently likely, then the loan size is strictly increasing over time along the equilibrium path of all non-trivial equilibria. As such, this paper helps explain gradualism in long-term relationships, especially credit relationships.
On structural decompositions of finite frames

A frame in an n-dimensional Hilbert space Hn is a possibly redundant collection of vectors {fi}i?I that span the space. A tight frame is a generalization of an orthonormal basis. A frame {fi}i?I is said to be scalable if there exist nonnegative scalars {ci}i?I such that {cifi}i?I is a tight frame. In this paper we study the combinatorial structure of frames and their decomposition into tight or scalable subsets by using partially-ordered sets (posets). We define the factor poset of a frame {fi}i?I to be a collection of subsets of I ordered by inclusion so that nonempty J⊆I is in the factor poset iff {fj}j?J is a tight frame for Hn. We study various properties of factor posets and address the inverse factor poset problem, which inquires when there exists a frame whose factor poset is some given poset P. We then turn our attention to scalable frames and present partial results regarding when a frame can be scaled to have a given factor poset; in doing so we present a bridge between erasure resilience (as studied via prime tight frames) and scalability.
Where Does the Money Go? Best and Worst Practices in Foreign Aid

This paper does not address the issue of aid effectiveness -- that is, the extent to which foreign aid dollars actually achieve their goals -- but on "best practices" in the way in which official aid is given, an important component of the wider debate. First we discuss best practice for an ideal aid agency and the difficulties that aid agencies face because they are typically not accountable to their intended beneficiaries. Next we consider the transparency of aid agencies and four additional dimensions of aid practice: specialization, or the degree to which aid is not fragmented among too many donors, too many countries, and too many sectors for each donor); selectivity, or the extent to which aid avoids corrupt autocrats and goes to the poorest countries; use of ineffective aid channels such as tied aid, food aid, and technical assistance; and the overhead costs of aid agencies. We compare 48 aid agencies along these dimensions, distinguishing between bilateral and multilateral ones. Using the admittedly limited information we have, we rank the aid agencies on different dimensions of aid practice and then provide one final comprehensive ranking. We present these results as an illustrative exercise to move the aid discussion forward.
The abundance effect: Unethical behavior in the presence of wealth

Three laboratory studies investigated the hypothesis that the presence of wealth may influence people’s propensity to engage in unethical behavior for financial gain. In the experiments, participants were given the opportunity to cheat by overstating their performance on an anagram task. In each study, one group was stimulated by the visible proximity of monetary wealth. We found that the presence of abundant wealth led to more frequent cheating than an environment of scarcity. Our experiments also investigated the potential mechanisms behind this effect. The results showed that the presence of abundant wealth provoked feelings of envy toward wealthy others that, in turn, led to unethical behavior. Our findings offer insights into when and why people engage in unethical behavior.
The Presumption of Liberty and the Public Interest: Medical Marijuana and Fundamental Rights

As part of this lecture series on lawyering in the public interest, the author decided to talk about his pro bono involvement in the medical cannabis case of Gonzales v. Raich, which he and three other lawyers brought on behalf of Angel Raich and Diane Monson. There are three topics discussed in this lecture: the first is how the author got involved in doing this, which is a question he is asked all the time; the second is to describe the theory they took to the Supreme Court, which prevailed in the Ninth Circuit but was ultimately rejected by the Court on a vote of six to three; and finally, because the case still continues, the author explains their current claims, which are based on the Due Process Clause of the Fifth Amendment and on the Ninth Amendment. In particular, he discusses how our current theory relates to constitutional law class teachings. The author argues that the problems faced in his case illustrate the weakness of the current approach to using the Due Process Clause to protect liberty and why a "presumption of liberty," which he has argued for in his scholarship, would be preferable to the current approach.
Successful failure: what Foucault can teach us about privacy self-management in a world of Facebook and big data

The "privacy paradox" refers to the discrepancy between the concern individuals express for their privacy and the apparently low value they actually assign to it when they readily trade personal information for low-value goods online. In this paper, I argue that the privacy paradox masks a more important paradox: the self-management model of privacy embedded in notice-and-consent pages on websites and other, analogous practices can be readily shown to underprotect privacy, even in the economic terms favored by its advocates. The real question, then, is why privacy self-management occupies such a prominent position in privacy law and regulation. Borrowing from Foucault's late writings, I argue that this failure to protect privacy is also a success in ethical subject formation, as it actively pushes privacy norms and practices in a neoliberal direction. In other words, privacy self-management isn't about protecting people's privacy; it's about inculcating the idea that privacy is an individual, commodified good that can be traded for other market goods. Along the way, the self-management regime forces privacy into the market, obstructs the functioning of other, more social, understandings of privacy, and occludes the various ways that individuals attempt to resist adopting the market-based view of themselves and their privacy. Throughout, I use the analytics practices of Facebook and social networking sites as a sustained case study of the point.
Legal Transplants v. Transnational Law: Lessons From the Israeli Adoption of Public Factors in Forum Non Conveniens

Legal transplants are an artifact of globalization, in that legal knowledge transcends borders and enables lawmakers, regulators, judges and lawyers to discover and import legal solutions for local problems in the global market of legal ideas. However, it is hasty to assert that legal transplants necessarily promote the globalization or the trans-nationalization of law. This paper argues some legal transplants should be viewed more suspiciously than others, particularly in a world in which it is essential to enhance international comity and forge a network of globally committed national courts that will further effective transnational litigation. Legal transplants regarding procedural law that bear on foreign plaintiffs’ access to local judicial systems should raise concern. This paper will demonstrate the dangers of jurisdiction transplants by analyzing the haphazard path in which Israeli courts adopted and implemented the U.S. mechanism of weighing public factors in the application of the forum non conveniens doctrine.
Evaluating sponsorship through the lens of the resource-based view: The potential for sustained competitive advantage

Abstract The resource-based view (RBV) of the firm has become a prominent management theory that firms can use to analyze resources as potential sources of competitive advantage. Theorists have suggested sponsorship of sport properties as one such resource, yet specific cases of sponsorship's role in a firm's achievement of a sustained advantage over competitors have yet to be explored. This article illuminates the case of Visa's longstanding global sponsorship of the Olympic Games, which was initiated and leveraged to counteract competitor American Express’ advantage with global business travelers. Evidence is presented that supports Visa's achievement of a competitive advantage during the term of the sponsorship. The case is then used to develop a conceptual model based on the RBV to identify the key characteristics of sponsored properties capable of assisting the sponsoring firm in achieving a sustained competitive advantage. From a managerial perspective, the model is designed to assist marketing managers tasked with the identification and evaluation of potential sponsorship properties.
Retrospective Causal Inference with Machine Learning Ensembles: An Application to Anti-recidivism Policies in Colombia

We present new methods to estimate causal effects retrospectively from micro data with the assistance of a machine learning ensemble. This approach overcomes two important limitations in conventional methods like regression modeling or matching: (i) ambiguity about the pertinent retrospective counterfactuals and (ii) potential misspecification, overfitting, and otherwise bias-prone or inefficient use of a large identifying covariate set in the estimation of causal effects. Our method targets the analysis toward a well-defined â€œretrospective intervention effectâ€ based on hypothetical population interventions and applies a machine learning ensemble that allows data to guide us, in a controlled fashion, on how to use a large identifying covariate set. We illustrate with an analysis of policy options for reducing ex-combatant recidivism in Colombia.
Unilateralism in a Multilateral World

This paper addresses the interplay between unilateralism and multilateralism. I describe their stylised facts and present a simple, multi-country model with high initial tariffs and features that have always been of paramount concern to policy makers, and allow governments to negotiate multilateral agreements. I then find a role for a system with features remarkably similar to contemporary unilateralism. The relationships between multilateralism and unilateralism are subtle: Unilateralism has the properties it has because the world is multilateral (the insurancetriangle); useful unilateralism requires a multilateralcomponent resulting from a compatibility problem between those who negotiate multilaterally and those who establish unilateralism.
Labored Law: Bilateralism or Pluralism, Ossification or Reformation

Reforming labor law policy and suggestions for overhauling the 1935 National Labor Relations Act.
Detecting Effects of Living Wage Laws

We estimate the effects of living wage laws on wages of low-wage workers, focusing on the timing of policy, spurious associations, and the type of living wage law passed in a city. Our estimates point to sizable positive wage effects in cities with broad living wage laws that cover employers receiving business assistance from the city. We also explore disemployment effects of living wage laws and find evidence consistent with tradeoffs between wages and employment.
If It's Good for the Firm, It's Good for Me: Insider Trading and Repurchases Motivated by Undervaluation

My findings suggest that information inherent in insider trading can be used to identify undervalued repurchasing firms. I examine the relation between insider trading and the performance of open market repurchase (OMR) firms. I show that firms with high net insider buying prior to OMR announcements not only earn abnormal stock returns in both the short- and long-run, but also exhibit better operating performance. Overall, the evidence is consistent with insiders timing their trades prior to OMR announcements.
AN ESTIMABLE DYNAMIC GENERAL EQUILIBRIUM MODEL OF WORK, SCHOOLING, AND OCCUPATIONAL CHOICE

This paper develops and estimates a dynamic general equilibrium overlapping generations model of career decisions. The model is fit to data on life cycle employment, schooling and occupation decisions, and on life cycle labor earnings, within and between cohorts observed in the US between 1968 and 1993. Based on the estimates of the model, the impact of cohort size on skill prices and, consequently, on career decisions is assessed. Compared to a baseline case in which cohort size increased at a steady (average) rate and the fertility process was stationary, it is found that the male baby bust generations born in the 1930s and 1940s faced higher skill prices (by as much as 2.0%), completed college at a higher rate (by as much as 0.3 percentage points) and worked more over the lifetime (by as much as 0.1 years). In contrast, the males from the baby boom generations born in the 1950s and 1960s faced lower skill prices (by as much as 1.5%), completed college at a lower rate (by as much as 1.0 percentage points) and worked less over the lifetime (by as much as 0.1 years). The impact of cohort size is found to differ across gender due to the differential impact of fertility on the value of home production: unlike males, the female baby bust generations completed college at a lower rate (by as much as 1.5 percentage points) and worked less over the lifetime (by as much as 0.5 years) while the female baby boom generations completed college at a lower rate (by as much as 1.5 percentage points) and worked more over the lifetime (by as much as 0.2 years). A tuition subsidy experiment is also performed both in a general equilibrium setting in which skill prices are endogenous and in a partial equilibrium setting with fixed skill prices. Based on the estimated model, a 1% increase in tuition is predicted to reduce college enrollment rates by 1.27% in partial equilibrium, consistent with previous estimates, and by 1.05% in the general equilibrium case. Thus, for this policy experiment, the partial equilibrium analysis of schooling choice would not differ significantly from the general equilibrium analysis.
Enzyme Promiscuity Prediction Using Hierarchy-Informed Multi-Label Classification.

MOTIVATION As experimental efforts are costly and time consuming, computational characterization of enzyme capabilities is an attractive alternative. We present and evaluate several machine-learning models to predict which of 983 distinct enzymes, as defined via the Enzyme Commission (EC) numbers, are likely to interact with a given query molecule. Our data consists of enzyme-substrate interactions from the BRENDA database. Some interactions are attributed to natural selection and involve the enzyme's natural substrates. The majority of the interactions however involve non-natural substrates, thus reflecting promiscuous enzymatic activities. RESULTS We frame this "enzyme promiscuity prediction" problem as a multi-label classification task. We maximally utilize inhibitor and unlabelled data to train prediction models that can take advantage of known hierarchical relationships between enzyme classes. We report that a hierarchical multi-label neural network, EPP-HMCNF, is the best model for solving this problem, outperforming k-nearest neighbours similarity-based and other machine learning models. We show that inhibitor information during training consistently improves predictive power, particularly for EPP-HMCNF. We also show that all promiscuity prediction models perform worse under a realistic data split when compared to a random data split, and when evaluating performance on non-natural substrates compared to natural substrates. AVAILABILITY AND IMPLEMENTATION We provide Python code for EPP-HMCNF and other models in a repository termed EPP (Enzyme Promiscuity Prediction) at https://github.com/hassounlab/EPP. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
The impact of revolving door practice and policy on nonprofessional investors’ perceptions of auditor independence

This study investigates whether an ex-auditor’s employment with an audit client impairs nonprofessional investors’ perceptions of auditor independence, and whether the strength of the US revolving door policy improves their perceptions of auditor independence. Despite nonprofessional investors owning over one-third of the US equity holdings, the literature has not examined how revolving door policy impacts their perceptions of auditor independence. Two between-subjects experiments examine these issues. The first experiment finds that investors perceive the ex-auditor’s integrity to be significant in explaining the firm’s decision to manage earnings, irrespective of the firm’s previous working relationship with the ex-auditor. The results from experiment two indicate that strengthening the revolving door policy above that of the American Institute of Certified Public Accountants’ policy does not improve perceptions of auditor independence. Academics may be interested in triangulating the independence ‘in a...
The valuation consequences of voluntary accounting changes

Firm management typically claims that voluntary accounting method changes (VACs) are made to enhance the informativeness of earnings by better matching accounting practices with economic reality. In contrast, skeptics argue that managers adopt new accounting procedures to opportunistically manage earnings and influence their firm’s stock price. In this paper, we investigate these alternative motives for VACs. Specifically, we investigate whether VACs cause equity prices to deviate from their fundamental values in the short-term by studying the long-run stock-price performance for a sample of firms that voluntarily change accounting methods. In addition, we investigate changes in earnings informativeness by examining the behavior of earning response coefficients and the relationship between earnings and future cash flows in years surrounding the VAC event. In contrast to prior research, we find little evidence that a strategy based solely on the earnings effect of a VAC can generate abnormal returns. While we find weak evidence of post-VAC abnormal returns for extreme VACs, this result appears to be driven by the accruals anomaly documented in Sloan [Sloan, R. G. (1996). The Accounting Review, 71, 289–315]. Our evidence further suggests that earnings informativeness is not significantly altered by voluntary changes in accounting methods. Taken together, our evidence suggests the market recognizes the financial statement effects of alternative acceptable accounting methods and efficiently processes the valuation implications of VACs.
The Role of Defined Benefit Pension Plans in Executive Compensation

AbstractAlthough defined benefit (DB) pension plans constitute a significant portion of both annual compensation and firm-related wealth for many CEOs, prior studies of CEO compensation contracts generally exclude these plans from their analyses due to lack of data. Taking advantage of recently increased disclosure requirements, we analyse the role of DB pension plans in these contracts. We find that firms with CEO DB pension plans grant the CEO annual compensation that is larger than predicted by economic determinants. We also find that more powerful CEOs, identified by their extraordinary pension benefits, receive higher total pay in addition to the pension benefits. We find no evidence that CEO pension benefits contribute to the pay-for-performance sensitivity of the annual pay.
Structural Unemployment in Luxembourg: Bad Luck or Rational Choice?

This paper combines both micro and macro approaches to identify the drivers of (un)employment and inactivity in Luxembourg. The young, low-skilled, and non-EU migrants are found to be the most vulnerable groups in the labor market. In addition to skills mismatches, work disincentives embedded in the tax-benefit system constitute a factor explaining structural unemployment. High unemployment of young and low-skilled workers reflects substantial unemployment traps, while disincentives for second earners (respectively the generosity of the pension system) contribute to lower labor market participation of women (respectively seniors). Further reduction of structural unemployment requires better integration of vulnerable groups into the labor market and improved targeting of benefits to make work more rewarding.
Single Peaked Vs. Diversified Capitalism: The Relation Between Economic Institutions and Outcomes

Capitalist countries have historically had quite different labour market institutions and social policies: high mobility and flexibility in the United States, lifetime employment and steep seniority profiles in Japan, corporatism in the Nordic countries and Austria, apprenticeships in Germany, the SMIC minimum wage and legislated work-time in France. Throughout the EU, ‘social partners’ negotiate arrangements, whereas in North America the term has no meaning. The labour market is potentially the most idiosyncratic market in advanced capitalism.
Russian Health Care Reform at the Regional Level: Status and Impact

(2001). Russian Health Care Reform at the Regional Level: Status and Impact. Post-Soviet Geography and Economics: Vol. 42, No. 3, pp. 202-219.
IS HEALTH INSURANCE AFFORDABLE FOR THE UNINSURED

In this paper, we investigate the meaning of "affordability" in the context of health insurance. Assessing the relationship between the affordability of coverage and the large number of uninsured in the U.S. is important for understanding the barriers to purchasing coverage and evaluating the role of policy in reducing the number of uninsured. We propose several definitions of affordability and examine the implications of alternative definitions for estimates of the proportion of uninsured who are unable to afford coverage. We find that, depending on the definition, health insurance was affordable to between one-quarter and three-quarters of the uninsured in the United States in 2000.
Sell-side analyst research and stock comovement

We document that a stock's price around a recommendation or forecast covaries with prices of other stocks the issuing analyst covers. The effect of shared analyst coverage on stock price comovement extends beyond analyst activity days. A stock's daily returns covary with the returns of other stocks with which it shares analyst coverage. These links between stock price comovement and shared analyst coverage are consistent with the coverage-specific information we find in earnings forecasts; analysts who cover both stocks in a pair expect future earnings of the stocks to be more highly correlated than do analysts who cover only one stock from the pair. Collectively, our evidence indicates that analyst research produces coverage-specific spillovers that raise price comovement among stocks that share analyst coverage. The strength of these spillovers is comparable to spillovers from broad industry and market information in analyst research.
Maximum likelihood estimation of stochastic volatility models

Abstract We develop and implement a method for maximum likelihood estimation in closed-form of stochastic volatility models. Using Monte Carlo simulations, we compare a full likelihood procedure, where an option price is inverted into the unobservable volatility state, to an approximate likelihood procedure where the volatility state is replaced by proxies based on the implied volatility of a short-dated at-the-money option. The approximation results in a small loss of accuracy relative to the standard errors due to sampling noise. We apply this method to market prices of index options for several stochastic volatility models, and compare the characteristics of the estimated models. The evidence for a general CEV model, which nests both the affine Heston model and a GARCH model, suggests that the elasticity of variance of volatility lies between that assumed by the two nested models.
THE REDUCTION OF CAUSAL PROCESSES

The principle that causes always render their effects more likely is fundamental to the enterprise of reducing facts of causation to facts about (objective) chances. This reductionist enterprise faces famous difficulties in accommodating common-sense intuitions about causal processes, if it insists on cashing out causal processes in terms of streams of events in which every event that belongs to the stream is a cause of the adjoining event downstream of it. I shall propose modifications to this way of cashing out causal processes, still well within the reductionist faith. These modifications will allow the reductionist to handle processes successfully, on the assumption that the reductionist proposal is itself otherwise satisfactory. I shall then argue that the reductionist enterprise lies squarely behind the Theory of Relativity, and so has all the confirmatory weight of Relativity behind it. However this is not all good news for reductionists. For throughout I shall simply assume that the reductionist proposal, to the effect that causes are just chance-raisers, is correct. AndI shall sidestep problems with that proposal as such. And so I shall show that, if in the end we find the reductionist proposal unsatisfactory, it cannot be on grounds of its treatment of causal processes as such. Thus, while I shall argue that causal processes pose no extra trouble for redutionists, I shall be making a case that all the action between reductionists and their opponents should be focused upon the proposal to reduce the two-term causal relation itself to relations amongst probabilities.
Infected judgment: legal responses to physician bias.

Substantial evidence indicates that clinically irrelevant patient characteristics, including race and gender, may at times influence a physician's choice of treatment. Less clear, however, is whether a patient who is the victim of a biased medical decision has any effective legal recourse. Heedful of the difficulties of designing research to establish conclusively the role of physician bias, this article surveys published evidence suggesting the operation of physician bias in clinical decision making. The article then examines potential legal responses to biased medical judgments. A patient who is the subject of a biased decision may sue her doctor for violating his professional duties, including his fiduciary obligation to the patient. Courts may be unwilling, however, to expand the scope of physicians' professional liability beyond existing medical malpractice law. While federal anti-discrimination laws may prohibit some instances of biased medical decisions, those laws leave many instances of physician bias unaddressed. Moreover, those laws typically would require a patient to prove that her doctor acted intentionally in discriminating, a daunting task if the physician's bias is unconscious, as is probably often the case. Finally, under either a professional liability action or a civil rights suit, the patient faces the fundamental problem of proving that bias in fact infected her physician's judgment. Because of these difficulties, the article concludes that existing law does not provide a ready remedy for a patient who is the victim of a biased medical decision.
Developments in the Fields of Accounting and Tax

This article discusses recent developments in the accounting and tax fields. The two accounting developments discussed are (1) (FASB's proposal to eliminate the pooling of interests method of accounting for a business combination, and (2) FASB's decision to test goodwill for impairment. The seven tax law developments discussed are (1) the Timber Group's Morris Trust transaction, (2) Ford's recapitalization, (3) Chris-Craft's merger, (4) deductibility of tangible acquisition costs, (5) the Service's easing of the continuity of interest requirement, (6) spin-offs preceded by a control gathering recapitalization, and (7) the proposed section 355 regulations.