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The interconnection of repertoires is a behavioral process related to problem solving and creativity. Experiments on this topic have mostly used a single reinforcer type during training. Reinforcers have an integrative effect on the emergence of new behavior; however, this assumption was never directly tested in procedures that result in the emergence of the interconnection of repertoires. To test this, six pigeons learned to: (1) push a box towards a light and (2) climb a box and peck a target. After training, pigeons were exposed to the box displacement test, a problem situation that required both behaviors to be solved. Two birds were trained with food as reinforcer for both repertoires (control condition [CC]), and four birds (experimental condition [EC]) had food as reinforcer for repertoire (1), and water for (2). CC birds solved the test in its first presentation, but EC birds did not. Birds that failed the test twice received a retraining of both repertoires, using only food as reinforcer. Half of the pigeons who received this retraining solved the task in a third trial. All pigeons that solved the task (n = 4) were given variations of the task consisting of introducing new stimuli, which, when physically similar to the functional stimuli, hindered the solution. These data indicate that the reinforcer has a similar integrative and discriminative function during the interconnection of repertoires as observed in other behavioral processes related to emergent behavior. The implications of these findings for research on creativity are discussed. Keywords Insight * Creativity * Problemsolving * Novel behavior * Pigeons, Epstein, Kirshnit, Lanza, and Rubin (1984) published an experiment in which pigeons (Columba livid) showed problemsolving performances akin to what classical experimenters in psychology termed 'insightful' problem solving, following the [...]

Introduction The Canadian federal government has proclaimed its commitment to diversity, equity and inclusion. In the context of the COVID-19 crisis which has amplified existing inequities, reconciliation with Indigenous peoples, [...]

Antoine Busnoys. Works with Texts in the Vernacular. Edited by Leeman L Perkins. (Antoine Busnoys, Collected Works, volume 1.) (Masters and Monuments of the Renaissance, volume 5.) New York: The [...]

We embed systematic default, procyclical recovery rates, and external habit persistence into a model with a slight possibility of a macroeconomic disaster of reasonable magnitude. We derive analytical solutions for defaultable bond prices and show that a single set of structural parameters calibrated to the real economy can simultaneously explain several key empirical regularities in equity, credit, and options markets. Our model captures the empirical level and volatility of credit spreads, generates a flexible credit risk term structure, and provides a good fit to a century of observed spreads. The model also matches high-yield and collaterized debt obligation tranche spreads, equity market moments, and index option skewness. Finally, our model implies a time-varying relationship between bond and option prices that depends on the state of the economy and that explains the conflicting empirical evidence found in the literature. History: Accepted by Jerome Detemple, finance. Funding: The authors gratefully acknowledge financial support from the Bank of Canada, the Global Risk Institute, Hong Kong Research Grants Council [CityU 640612], and Social Sciences and Humanities Research Council. Supplemental Material: The online appendix is available at https://doi.org/10.1287/mnsc.2015.2361. Keywords: credit spreads . volatility * term structure * option skewness * stochastic recovery * consumption risk, 1. Introduction We show that a model of rare macro disasters implemented using a single set of parameters can produce key stylized facts in equity, credit, and options markets when [...]

The extended Kalman filter, which linearizes the relationship between security prices and state variables, is widely used in fixed-income applications. We investigate whether the unscented Kalman filter should be used [...]

We present new evidence on disaggregated profit and loss (P/L) and value-at-risk (VaR) forecasts obtained from a large international commercial bank. Our data set includes the actual daily P/L generated by four separate business lines within the bank. All four business lines are involved in securities trading and each is observed daily for a period of at least two years. Given this unique data set, we provide an integrated, unifying framework for assessing the accuracy of VaR forecasts. We use a comprehensive Monte Carlo study to assess which of these many tests have the best finite-sample size and power properties. Our desk-level data set provides importance guidance for choosing realistic P/L-generating processes in the Monte Carlo comparison of the various tests. The conditional autoregressive value-at-risk test of Engle and Manganelli (2004) performs best overall, but duration-based tests also perform well in many cases. Key words: risk management; backtesting; volatility; disclosure History: Received July 30, 2007; accepted October 24, 2008, by John Birge, focused issue editor. Published online in Articles in Advance January 28, 2009., 1. Introduction In the financial services industry, a primary concern of money managers is the ongoing level of risk in their portfolios. For decades, the textbook measure of portfolio risk [...]

ABSTRACT Data sets on the natural dynamics of beach ecosystems are scarce and fragmentary. Such data are necessary for implementing more efficient monitoring programs that quantify the dynamics of key [...]

ABSTRACT. The High Arctic is one of the regions most susceptible to climate change on a global scale. Increased temperature, precipitation, and cloud cover are anticipated in the region, with [...]

State-of-the-art stochastic volatility models generate a 'volatility smirk' that explains why out-of-the-money index puts have high prices relative to the Black-Scholes benchmark. These models also adequately explain how the volatility smirk moves up and down in response to changes in risk. However, the data indicate that the slope and the level of the smirk fluctuate largely independently. Although single-factor stochastic volatility models can capture the slope of the smirk, they cannot explain such largely independent fluctuations in its level and slope over time. We propose to model these movements using a two-factor stochastic volatility model. Because the factors have distinct correlations with market returns, and because the weights of the factors vary over time, the model generates stochastic correlation between volatility and stock returns. Besides providing more flexible modeling of the time variation in the smirk, the model also provides more flexible modeling of the volatility term structure. Our empirical results indicate that the model improves on the benchmark Heston stochastic volatility model by 24% in-sample and 23% out-of-sample. The better fit results from improvements in the modeling of the term structure dimension as well as the moneyness dimension. Key words: stochastic correlation; stochastic volatility; equity index options; multifactor model; persistence; affine; out-of-sample History. Received March 2, 2007; accepted June 16, 2009, by David A. Hsieh, finance. Published online in Articles in Advance September 11, 2009., 1. Introduction An extensive empirical literature has documented the empirical biases of the Black and Scholes (1973) option valuation model for the purpose of the valuation of equity index options. [...]

The use of animal models in diabetes research requires reliable tests for evaluation of insulin sensitivity and [beta]-cell function. Minipigs are being increasingly used in metabolic research, and the aim of this study was to compare different tests and indexes for evaluation of insulin sensitivity and [beta]-cell function in Grttingen minipigs. Hyperinsulinemic, isoglycemic clamp, intravenous (IVGTT) and oral glucose tolerance tests (OGTT), and a modified insulin tolerance test were performed in minipigs fed either low- or high-energy diet. Furthermore, the reproducibility of IVGTT-derived parameters was assessed. Previously described insulin sensitivity indexes [steady-state glucose infusion rate/glucose concentration/insulin concentration from clamp (M/G/I); oral glucose insulin sensitivity (OGIS) and [ISI.sub.comp] from OGTT; [S.sub.1] from minimal model analysis of IVGTT; and quantitative insulin sensitivity check index from fasting values] were calculated together with an insulin sensitivity index from the modified insulin tolerance test ([ISI.sub.ITT]) and a new simple index (S2) derived from the first 30 min of the IVGTT. [beta]-Cell function was assessed from the IVGTT and the OGTT. Reproducibility of the IVGTT-derived parameters was calculated as median intraindividual coefficient of variation (CV%).M/G/I correlated significantly only with S2 (P < 0.05, r = 0.54). $2 furthermore correlated with [S.sub.1] (P < 0.001, r = 0.81), [ISI.sub.ITT] (P < 0.001, r = 0.57), and the two indexes from OGTT, [ISI.sub.comp] (P < 0.001, r = 0.78) and OGIS (p < 0.05, r = 0.48). No correlation was found between [beta]-cell function indexes from OGTT and IVGTT. The median CV% of the new S2 index was 13. In conclusion, the new simple index of insulin sensitivity, S2, was revealed to be useful for evaluation of insulin sensitivity in pigs. glucose tolerance; [beta]-cell function; intravenous glucose tolerance test; oral glucose tolerance test; clamp doi: 10.1152/ajpregu.90851.2008

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jfineco.2008.06.001 Byline: Susan E.K. Christoffersen, Sergei Sarkissian Keywords: Information spillovers; Labor market; Mutual funds; Performance evaluation Abstract: The literature predicts that the average skill level and productivity are higher in larger cities. Prior studies use workers' wage or education differentials to indirectly link city size and output. This article relates city size and productivity directly, using performance data of U.S. equity mutual funds. On average, funds in financial centers perform better than other funds in terms of both gross and risk-adjusted returns, but this difference is driven only by more experienced managers. Among funds in financial centers there is strong evidence of a positive relation between performance and manager experience in a given city, especially among New York funds. More importantly, we observe performance improvements of the same manager at the same fund in financial centers but not elsewhere. Our tests provide novel evidence of knowledge spillovers and learning in cities. Author Affiliation: Desautels Faculty of Management, McGill University, Montreal, Canada H3A1G5 Article History: Received 6 November 2007; Revised 5 May 2008; Accepted 3 June 2008 Article Note: (footnote) [star] We are grateful to Wayne Ferson, Edward Glaeser, Tobias Moskowitz, David Musto, Michael Schill, Tyler Shumway, Bill Strange, Bill Schwert (the editor), Rene Stulz, Jay Wang, Ivo Welch, and especially an anonymous referee, for helpful comments. This paper has also benefited from suggestions of seminar participants at Copenhagen Business School, Cornell University, Hong Kong University of Science and Technology, Laval University, McGill University, University of Michigan, University of Toronto, University of Virginia (Darden School), and University of Washington, as well as participants of the 2001 European Finance Association Meeting, the 2002 BSI Gamma Mutual Fund Conference, the 2004 INQUIRE-Europe Meeting, and the 2007 American Association Meeting. We thank John Bromley, Carlos Cortes, Lance Dexter, Feriel Feghoul, Eric Turner, and Maximo Aybar for help organizing the data. We also thank Rich Evans, Morningstar Inc., the College Board, and Lipper Analytical for providing parts of the data. Part of this paper was written while Christoffersen was visiting the Copenhagen Business School. The authors acknowledge financial support from the Swiss Finance Institute, BSI Gamma Foundation, SSHRC, and IFM2, as well as the CSI Research Foundation (Christoffersen), and FQRSC (Sarkissian).

Research was conducted on reproductive tract infections among women obtaining induced abortions at Phu-San hospital in Haiphong City, a major maternity hospital in northern Vietnam. The research aimed to explore how clinicians and lab-technicians diagnose reproductive tract infections and the difficulties they experience in establishing exact diagnoses. A combination of both quantitative and qualitative research methodologies was employed. The quantitative research involved 748 abortion-seeking women; the qualitative research was conducted with 10 doctors and 10 lab-technicians providing reproductive health services. A marked tendency was observed among both clinicians and lab-technicians to overdiagnose reproductive tract infections and to prescribe antibiotics routinely. Social, cultural, and clinical factors associated with the tendency to overdiagnose reproductive tract infections included: inadequate training of health staff, lack of equipment, and cultural assumptions regarding the overwhelming prevalence of reproductive tract infections in Vietnamese women, especially among those who receive abortion services. Misconceptions of reproductive tract infections led to substantial over-diagnosis and unnecessary treatment of reproductive tract infections in this hospital. To enhance reproductive tract infection care, providers need to be sensitized to the social and medical consequences of their own cultural perceptions and to increase their awareness of the risks associated with overuse of antibiotics. KEYWORDS reproductive tract infections, clinical diagnosis, laboratory diagnosis, induced abortion, women

Subglacial lakes identified beneath the Antarctic Ice Sheet belong to a rare category of unexplored environments on Earth's surface. The key to understanding the origin and longevity of subglacial lakes is likely contained in their sedimentary sequences. Here we explore the nature of a sedimentary succession in a deep tectonic trough identified as a prime candidate for a large subglacial paleolake. The trough is the 100-km-long, 620-m-deep Christie Bay, located in the east arm of the Great Slave Lake, Canada. High-resolution seismic reflection data and short sediment cores collected in the deep trough show a 150-m-thick sequence of fine-grained sedimentary lake fill separating glacial ice-contact deposits from draped Holocene lake sediments. We interpret this sequence to consist of sediments that accumulated in a subglacial lake that covered an area larger than 130 [km.sup.2]. The inferred presence of a subglacial paleolake is supported by results from hydrologic modeling of drainage pathways beneath the Laurentide Ice Sheet during the last glacial maximum. Our data point toward the existence of a dynamic subglacial lake environment where sediments were delivered by discharge of meltwater from a subglacial water system. A core sample of the sedimentary lake fill in Christie Bay may elucidate whether living organisms exist in subglacial lakes. Keywords: subglacial lake, ice sheet, sediment, hydrology, basal water.

Using a complete birth cohort of all young men born in 1966 in Denmark (N = 43,403), the prevalence of a first-time drink-driving conviction among young men is estimated. More than 7% of the total male birth cohort was so convicted before the age of 27 years. In an examination of risk factors for a first-time drink-driving conviction, young adults coming from potentially vulnerable groups have an increased risk. Earlier criminal convictions of various types were also significant predictors of drink driving. Situational pressures also play a part and are controlled for, with the risk of a drink-driving conviction increased substantially in rural areas compared to metropolitan areas. The study concludes that disadvantages during adolescence, including parental substance abuse, having a teenage mother, and domestic violence, are associated with a first-time drink-driving conviction. Keywords: Driving under the influence; Drink driving; Conviction; Childhood factors; Risk factors; Life course

In 2006 Odin Teatret performed its multicultural version of Ur-Hamlet, derived from its early thirteenth-century origins in the Gesta Danorum of Saxo Grammaticus, in the castle courtyard of Kronborg--the Elsinore setting for Shakespeare's version four centuries later. But the performance here followed years of preparation, and involved a multiplicity of theatre styles and performing traditions. The production had its beginnings at sessions of the International School of Theatre Anthropology (ISTA) in Seville in 2004 and Wroclaw in 2005, and preparations continued in Holstebro, Copenhagen, and Bali from 2004 to 2006. Erik Exe Christoffersen followed the final rehearsals in Ravenna, and here gives an account of the Kronborg performance. Erik Exe Christoffersen is Associate Professor at the Institut for AEstetiske Fag, Department for Dramaturgy, Aarhus University, Denmark. His most recent publications include The Actor's Way (Routledge, 1993) and Teaterhandlinger (Theatre Actions, 2007). He is Editor of the Danish theatre journal Peripeti: Tidskrift for Dramaturgiske Studier.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2007.12.009 Byline: Sigrun H. Jonasdottir (a), Katherine Richardson (b), Michael R. Heath (c), Anna Ingvarsdottir (d), Alice Christoffersen (a) Keywords: North Atlantic; Calanus finmarchicus; Secondary production; Fatty acids; Hatching; Lipid content Abstract: Distribution and reproduction activity of the calanoid copepod Calanus finmarchicus were studied in the waters between Scotland and Iceland in April 1997 during the expected time of the animals' ascent to surface waters following diapause. Ascent was taking place on both sides of the Iceland-Scotland Ridge, apparently from two separate overwintering centers. The population on the Faroe Shelf (FS) most likely came from the overwintering population in the Faroe Shetland Channel (FSC). Per capita egg production was highest on the FS (>30eggsfemale.sup.-1 d.sup.-1) and lowest in the Iceland Basin (10eggsfemale.sup.-1 d.sup.-1). The maximum clutch size recorded was on the FS (145 eggs). As the maximum clutch sizes that females produced were between 40% and 77% (area averages of the station maximum rates) of their size-specific reproduction potential, it is argued that egg production rates were generally food-limited. Chlorophyll a concentrations were, at all but one station, under 1[mu]gL.sup.-1. Chlorophyll-based ingestion could, theoretically, support the observed average egg production rates in the Iceland Basin and on the FS but only about 30% of the observed production at the stations in the East Icelandic Current (EIC). The carbon assimilated through ingestion of phytoplankton, Calanus own eggs and nauplii in the EIC was estimated to be too low to support the frequently observed production of clutches consisting of over 100 eggs. Cannibalism on eggs and nauplii was not likely to have constituted a significant component of dietary carbon intake. However, a combination of feeding and assimilation of reserved lipid remaining from overwintering could be sufficient to explain the observed per capita egg production rates. C. finmarchicus copepod stages 1-3 were only recorded in considerable numbers only on the FS. This suggests higher survival rates of eggs in the shelf waters. Author Affiliation: (a) National Institute of Aquatic Resources, Technical University of Denmark, Kavalergaarden 6, DK 2920 Charlottenlund, Denmark (b) Department of Marine Ecology, Aarhus University, DK-8200 Aarhus, Denmark (c) Fisheries Research Service, Aberdeen Marine Laboratory, Aberdeen AB9 8DB, UK (d) School of Biological Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK Article History: Received 16 July 2006; Revised 18 December 2007; Accepted 26 December 2007

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1540-6261.2007.01296.x Byline: SUSAN E.K. CHRISTOFFERSEN, CHRISTOPHER C. GECZY, DAVID K. MUSTO, ADAM V. REED (*) Abstract: ABSTRACT The standard analysis of corporate governance assumes that shareholders vote in ratios that firms choose, such as one share-one vote. However, if the cost of unbundling and trading votes is sufficiently low, then shareholders choose the ratios. We document an active market for votes within the U.S. equity loan market, where the average vote sells for zero. We hypothesize that asymmetric information motivates the vote trade and find support in the cross section. More trading occurs for higher-spread and worse-performing firms, especially when voting is close. Vote trading corresponds to support for shareholder proposals and opposition to management proposals. Article note: (*) Christoffersen is with McGill University, Geczy and Musto are with the University of Pennsylvania, and Reed is with the University of North Carolina. The authors thank the editor, the associate editor, and an anonymous referee. We have greatly benefited from helpful advice and comments from Renee Adams, Bernard Black, Diane Del Guercio, Henry Hu, Jonathon Karpoff, Laurence Lescourret, Paul Malatesta, Ron Masulis, Randall Meades, Felix Meschke, Micah Officer, Artur Raviv, Honorable Leo Strine, Jr., Ralph Walkling, Lucy White, other sources who prefer to remain anonymous, and numerous seminar participants. We are grateful for financial support from SSHRC, FQRSC, IFM2, Canadian Securities Institute Research Foundation, and the Rodney L. White Center for Financial Research, and for research assistance from Jeff Ng, Eric Turner, Tristan Musgrave, and Michelle Zhang.

Quorum sensing (QS) denotes a density-dependent mode of inter-bacterial communication based on signal transmitter molecules. Active QS is present during chronic infections with the opportunistic pathogen Pseudomonas aeruginosa in immunocompromised patients. The authors have previously demonstrated a QS-regulated tolerance of biofilm bacteria to the antimicrobial properties of polymorphonuclear leukocytes (PMNs). The precise QS-regulated effect on the PMNs is, however, unknown. Incubation of human PMNs with supernatants from dense P. aeruginosa cultures showed that the QS-competent P. aeruginosa induced rapid necrosis of the PMNs. This mechanism was also observed in mouse lungs infected with P. aeruginosa, and in sputum obtained from P.-aeruginosa-infected patients with cystic fibrosis. Evidence is presented that the necrotic effect was caused by rhamnolipids, production of which is QS controlled. The results demonstrate the potential of the QS system to facilitate infections with P. aeruginosa by disabling the PMNs, which are a major first line of defence of the host. Furthermore, the study emphasizes the inhibition of QS as a target for the treatment of infections with P. aeruginosa. DOI 10.1099/mic.0.2006/003863-0

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jimonfin.2006.09.003 Byline: Peter Christoffersen (a), Hyunchul Chung (b), Vihang Errunza (a) Abstract: We attempt to answer the following questions: What are the revaluation effects and the impact on performance, volatility, and return correlation from stock market liberalization in emerging markets? These questions have been studied extensively at the market level but not at the firm level. Our results show significantly different impact of stock market liberalization across firms. Large firms tend to exhibit large revaluation effects, insignificant change in performance, large declines in volatility, and insignificant change in correlation from liberalization. Small firms show small revaluation effects, improved performance, smaller decline in volatility and decreases in correlation after liberalization. Author Affiliation: (a) Faculty of Management, McGill University, 1001 Sherbrooke Street West, Montreal, Quebec, Canada H3A 1G5 (b) School of Business, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, South Korea

We consider three sets of phenomena that feature prominently in the financial economics literature: (1) conditional mean dependence (or lack thereof) in asset returns, (2) dependence (and hence forecastability) in asset return signs, and (3) dependence (and hence forecastability) in asset return volatilities. We show that they are very much interrelated and explore the relationships in detail. Among other things, we show that (1) volatility dependence produces sign dependence, so long as expected returns are nonzero, so that one should expect sign dependence, given the overwhelming evidence of volatility dependence; (2) it is statistically possible to have sign dependence without conditional mean dependence; (3) sign dependence is not likely to be found via analysis of sign autocorrelations, runs tests, or traditional market timing tests because of the special nonlinear nature of sign dependence, so that traditional market timing tests are best viewed as tests for sign dependence arising from variation in expected returns rather than from variation in volatility or higher moments; (4) sign dependence is not likely to be found in very high-frequency (e.g., dally) or very low-frequency (e.g., annual) returns; instead, it is more likely to be found at intermediate return horizons; and (5) the link between volatility dependence and sign dependence remains intact in conditionally non-Gaussian environments, for example, with time-varying conditional skewness and/or kurtosis. Key words: return sign dependence, market timing; prediction, 1. Introduction We consider three sets of phenomena that feature prominently in the financial economics literature: (1) approximate conditional mean independence (and hence little or no forecastability) in asset returns, [...]

Both atrial (ANP) and brain (BNP) natriuretic peptide affect development of cardiac hypertrophy and fibrosis via binding to natriuretic peptide receptor (NPR)-A in the heart. A putative clearance receptor, NPR-C, is believed to regulate cardiac levels of ANP and BNP. The renin-angiotensin system also affects cardiac hypertrophy and fibrosis. In this study we examined the expression of genes for the NPRs in rats with pressure-overload cardiac hypertrophy. The ANG II type I receptor was blocked with losartan (10 mg * [kg.sup.-1] * [day.sup.-1]) to investigate a possible role of the renin-angiotensin system in regulation of natriuretic peptide and NPR gene expression. The ascending aorta was banded in 84 rats during Hypnorm/Dormicum-isoflurane anesthesia; after 4 wk the rats were randomized to treatment with losartan or placebo. The left ventricle of the heart was removed 1, 2, or 4 wk later. Aortic banding increased left ventricular expression of NPR-A and NPR-C mRNA by 110% (P < 0.001) and 520% (P < 0.01), respectively, after 8 wk; as expected, it also increased the expression of ANP and BNP mRNAs. Losartan induced a slight reduction of left ventricular weight but did not affect the expression of mRNAs for the natriuretic peptides or their receptors. Although increased gene expression does not necessarily convey a higher concentration of the protein, the data suggest that pressure overload is accompanied by upregulation of not only ANP and BNP but also their receptors NPR-A and NPR-C in the left ventricle. losartan: angiotensin II type 1 receptor: renin

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jeconom.2005.01.010 Byline: Peter Christoffersen (a), Steve Heston (b), Kris Jacobs (a) Abstract: Index option prices differ systematically from Black-Scholes prices. Out-of-the-money put prices (and in-the-money call prices) are relatively high compared to the Black-Scholes price. Motivated by these empirical facts, we develop a new discrete-time dynamic model of stock returns with inverse Gaussian innovations. The model allows for conditional skewness as well as conditional heteroskedasticity and a leverage effect. We present an analytic option pricing formula consistent with this stock return dynamic. An extensive empirical test of the model using S&P500 index options shows that the new inverse Gaussian GARCH model's performance is superior to a standard existing nested model for out-of-the money puts. Author Affiliation: (a) Faculty of Management, McGill University and CIRANO, 1001 Sherbrooke Street West, Montreal, Quebec, Canada, H3A 1G5 (b) R.H. Smith School of Business, University of Maryland, 4447 Van Munching Hall, College Park, MD 20742-1815, USA

Index option prices differ systematically from Black-Scholes prices. Out-of-the-money put prices (and in-the-money call prices) are relatively high compared to the Black-Scholes price. Motivated by these empirical facts, we develop a new discrete-time dynamic model of stock returns with inverse Gaussian innovations. The model allows for conditional skewness as well as conditional heteroskedasticity and a leverage effect. We present an analytic option pricing formula consistent with this stock return dynamic. An extensive empirical test of the model using S&P500 index options shows that the new inverse Gaussian GARCH model's performance is superior to a standard existing nested model for out-of-the money puts. JEL classification: G12 Keywords GARCH; Out-of-sample; Jumps; Discrete-time model; Continuous-time limit

A focus on the international fundEs taxable and retirement accounts conflict which face various tradeoffs between capital gains and dividends, and fund managers response to these kind conflicting preferences of their investors is presented.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jfineco.2004.08.004 Byline: Susan E.K. Christoffersen (a), Christopher C. Geczy (b), David K. Musto (b), Adam V. Reed (c) Abstract: We consider how fund managers respond to the conflicting preferences of their investors. We focus on the conflict between the taxable and retirement accounts of international funds, which face different tradeoffs between dividends and capital gains. In principle, managers could resolve this conflict through dividend arbitrage, but a proprietary database of dividend-arbitrage transactions shows that in practice they cannot. Thus, managers must resolve it through their investment policies. We find robust evidence that managers with more retirement money favor the preferences of retirement investors and further evidence for this view in the difference between U.S. and Canadian funds' portfolio weights. Author Affiliation: (a) McGill University and CIRANO, Montreal, Que., Canada H3A 1G5 (b) The Wharton School, University of Pennsylvania, Philadelphia, PA 19104, USA (c) The Kenan-Flagler Business School, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA Article Note: (footnote) [star] The authors thank Larry Bauer, Marshall Blume, Laurence Booth, Francesca Carrieri, Peter Christoffersen, Jennifer Conrad, Rene Garcia, Sarah Holden, Bob McDonald, Randall Meades, Felix Meschke, Jack Mintz, Neal Pearson, Brian Reid, Steve Ross, Doug Shackelford, Rob Stambaugh, an anonymous referee, the editor, and other sources who prefer to remain anonymous. We are grateful for helpful advice and comments from numerous seminar participants, including those at the JFE and University of Oregon Conference on Delegated Portfolio Management. Financial support was provided by SSHRC, FQRSC, IFM2, and the Rodney L. White Center for Financial Research. We are also grateful for research assistance from Eric Turner, K.C. Chang, Sarah Coyer, and Victoria Von Krause.

We investigated the intestinal uptake and adverse effects of microcystins ingested with Microcystis on Daphnia galeata. The gut structure, blood microcystin concentration, appearance, and movements of Daphnia fed Microcystis PCC 7806 or a microcystin-deficient PCC 7806 mutant were monitored over time. Microcystins were rapidly taken up from the digestive cavity into the blood. This process apparently required a preceding disruption of the gut epithelium by an as-yet-unknown Microcystis factor. Once microcystins entered the blood, they affected the neuromuscular communication or another life function that influences major muscle systems. Consequently, the beat rates of the thoracic legs, mandibles, and second antennae as well as the activity of the foregut decreased, whereas the midgut muscles were stimulated. Finally, the animals exhibited symptoms of exhaustion and died. The present results suggest that an ingestion of between 10.2 ng and 18.3 ng of microcystin per 1 mg of Daphnia body fresh weight is sufficient to kill D. galeata within 2 d.

Characterizing asset return dynamics using volatility models is an important part of empirical finance. The existing literature on GARCH models favors some rather complex volatility specifications whose relative performance is usually assessed through their likelihood based on a time series of asset returns. This paper compares a range of GARCH models along a different dimension, using option prices and returns under the risk-neutral as well as the physical probability measure. We judge the relative performance of various models by evaluating an objective function based on option prices. In contrast with returns-based inference, we find that our option-based objective function favors a relatively parsimonious model. Specifically, when evaluated out-of-sample, our analysis favors a model that, besides volatility clustering, only allows for a standard leverage effect. Key words: option pricing; GARCH; risk-neutral pricing; parsimony; forecasting; out-of-sample, 1. Introduction The family of GARCH volatility models has become an important tool kit in empirical asset pricing and financial risk management. Following the work of Engle (1982) and Bollerslev [...]

Consistency should be maintained while selecting the loss function and the same loss function should be used in parameter estimation and model evaluation. For appropriate comparisons, it is important that during the comparisons of models, the estimation loss function should be the same.

The aim of this study is to consider whether parents' abuse of alcohol has an impact on children during their formative years. The research is based on data from 84,765 children born in Denmark in 1966. These children and their parents were followed between 1979 and 1993. Information was analyzed from government registers covering health, education, family separation, suicidal behavior, criminality, and unemployment, using a discrete time Cox-regression model. Results showed that the parents' alcohol abuse may frame the childhood with parental violence, very high occurrence of family separations, and often foster care. The parental abuse of alcohol may influence several long-term consequences for their 15- to 27-year-old children such as increased mortality, self-destructive behaviors (e.g. attempted suicide or drug addiction). Hospitalization due to violence, an increased risk of teenage pregnancy and unemployment were also seen more frequently among cases where the parents were alcohol abusers. Mothers' alcohol abuse seemed to be associated with higher occurrences of all the mentioned disadvantages. Keywords: Teenage childbearing; Suicide attempt; Violent crime; Youth unemployment; Mental illness

Benthic community responses to lake eutrophication are poorly understood relative to pelagic responses. We compared phytoplankton and periphyton productivity along a eutrophication gradient in Greenland, U.S., and Danish lakes. Phytoplankton productivity increased along the phosphorus gradient (total phosphorus [TP] = 2-430 mg [m.sup.-3]), but whole-lake benthic algal productivity decreased, substantially depressing increases in primary productivity at the whole-lake scale. In shallow, oligotrophic Greenland lakes, periphyton was responsible for 80-98% of primary production, whereas in Danish lakes with TP > 100 mg [m.sup.-3], phytoplankton were responsible for nearly 100% of primary production. Benthic contributions ranged from 5 to 80% depending on morphometry and littoral habitat composition in lakes with intermediate phosphorus concentrations. Thus, eutrophication was characterized by a switch from benthic to pelagic dominance of primary productivity. Carbon stable isotope analysis showed that the redistribution of primary production entailed a similar shift from periphyton to phytoplankton in the diets of zoobenthos. Benthic and pelagic habitats were energetically linked through food web interactions, but eutrophication eroded the benthic primary production pathway.

A unique electromagnetic (EM)--electrothermal global simulation tool based on a universal error concept is presented. The advantages of this electrothermal model are illustrated by comparison with a commercial electrothermal circuit simulator. The first description of a fully physical, electrothermal, microwave circuit simulation, based on coupling of the Leeds Physical Model of MESFETs and high electron-mobility transistors, to a microwave circuit simulator, fREEDA (NCSU), is presented. The modeling effort is supported by parallel developments in electrooptic and thermal measurement. The first fully coupled EM-electrothermal global simulation of a large microwave subsystem, here a whole spatial power combining monolithic-microwave integrated-circuit (MMIC) array, is described. The simulation is partially validated by measurements of MMIC array temperature rise and temperature dependent S-parameters. Electrothermal issues for spatial power combiner operation and modeling are discussed. The computer-aided-design tools and experimental characterization described, provide a unique capability for the design of quasi-optical systems and for the exploration of the fundamental physics of spatial power combining devices. Index Terms--Electromagnetic (EM) measurements, electromagnetic (EM) modeling, electrothermal effects, global modeling and simulation, microwave circuits, power devices, quasi-optical power combining, spatial power combiners, thermal measurements, thermal modeling.

Integrating active learning exercises into pedagogy has long been recommended for its impact on student motivation, retention, and depth of understanding. Despite the well-documented literature in this area, many economics classes are still conducted in the traditional 'chalk and talk' mode. To facilitate change, this paper details an active approach to understanding the allocation of goods under different economic regimes. This allocation exercise is described, examples of handouts are provided and student responses to the exercise are summarized., Introduction Although active learning exercises are widely acknowledged for their effectiveness, they are rarely employed in the teaching of Principles of Economics. There are various explanations for the intransigence of [...]

The toxic effects of microcystins on Daphnia spp. depends on the ingestion rate rather than a difference in susceptibility to the toxins. The microcystins are usually ingested in cell-bound form, and Daphnia apparently cannot distinguish between microcystin-producing cells and cells that do not contain microcystins.

Over half the money fund managers for low-performing institutional and retail funds waive their fees to improve net performance. High-performing retail funds use fee waivers to adjust net performance so as to increase expected fund flows.

Results reveal that promoters mediating fepD and YbdA expression exhibit substantial overlap at their --10 regions. Data suggest that the promoter activity, which is regulated by iron through Fur repressor, is dependent on the relative strength of the promoters.

Recombinant avocado 1-aminocyclopropyl-1-carboxylate (ACC) oxidase, a direct precursor to formation of ethylene, was expressed in Escherichia coli and used to set up an activity assay and to find a mechanism for the oxidase. Binding of a second molecule of ascorbic acid or ACC brings significant substrate inhibition. Important determinants of substrate binding were found.

A state-variable-based approach to the impulse response and convolution analysis of distributed microwave circuits is developed. The state-variable approach minimizes computation time and memory requirements. It allows the use of parameterized nonlinear device models, thus improving robustness. Soliton generation on a nonlinear transmission line is considered as an example. Index Terms - Circuit simulation, circuit transient analysis, convolution, nonlinear circuits, solitons, state variables.

This paper investigates the factors relevant to producing effective human factors design guidance, using the Engineering Data Compendium (EDC) as a research vehicle. A series of three exploratory experiments focusing on the factors that affect the usability, usefulness and viability of human factors handbooks was conducted. The results of these studies were interpreted in the context of the process by which the EDC was developed, leading to the following recommendations: (a) human factors guidance should be organized in a manner that is steeped in context; (b) human factors guidance should be based on an explicit requirements analysis; (c) the calibration of designers' perceptions of the cost of obtaining human factors information must be improved: (d) organizational policies must be changed to induce more effective information search behaviour. Keywords: information retrieval, handbooks, design, technology transfer

China's influence in shaping the political order in the Asia-Pacific is perceived as a threat by other countries due to its undefined strategy for political, military and economic expansion. Although its recent entrance to the Asia Pacific Economic Cooperation is viewed as a positive move, the country is still learning from American and Japanese 'grand strategies.' The undefined and changing policies makes China a real threat and unless the government makes any moves, the uncertainty that its Asian neighbors feel will continue.

INTRODUCTION The vast majority of experimental evaluations of interface design concepts reported in the literature have been conducted over a short period, usually ranging from a few hours to, at […], Results from evaluations of interface design concepts conducted over short durations may not generalize to longer time spans. In an attempt to address this issue, this paper presents a longitudinal study of the effect of interface design on skill acquisition in which participants' quasi-daily performance was observed over an unprecedented period of six months. The research was conducted in the context of DURESS II, a real-time, interactive thermal-hydraulic process control simulation that was designed to be representative of industrial systems. The performance of two interfaces was compared, one containing physical and functional (P + F) system representations based on the principles of the ecological interface design framework, and a more traditional interface based solely on a physical (P) representation. Participants were required to perform several control tasks, including start-up, tuning, shutdown, and fault management. The results indicate that the P interface led to significantly less-consistent performance than did the P + F interface; with the former, participants occasionally took up to 2 times longer to complete the required tasks, even after 5.5 months of daily practice. There was very little difference in average performance between the two groups. These results have important implications for designing interfaces that lead to efficient performance under normal operating conditions.

We sincerely thank both the editor and Michael Maddox for the opportunity to participate in this collegial debate centered on our article, 'A Longitudinal Study of the Effects of Ecological […]