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Proceedings of QG2010: The Third Workshop on Question Generation
These are the peer-reviewed proceedings of "QG2010, The Third Workshop on Question Generation". The workshop included a special track for "QGSTEC2010: The First Question Generation Shared Task and Evaluation Challenge".
QG2010 was held as part of The Tenth International Conference on Intelligent Tutoring Systems (ITS2010)
The “Competitive” Value of Music to Commercial Radio Stations
Our objective in this paper is to develop a methodology to infer from the behaviour and choices of broadcasters the “competitive” value they attach to the use of music, more precisely sound recordings, and to derive from such an inferred value the proper “competitive” copyright payments to be made to authors, composers, performers, and makers of sound recordings. We illustrate the methodology by applying it to Canadian data. The background is provided by the statement of case and supporting proof presented in the 2004 proceedings before the Copyright Board of Canada on the commercial radio tariff. The results called for a significant increase in copyright payments by Canada’s commercial radio industry: the proper competitive copyright payments should be substantially more than double what the industry was paying at the time of the hearings. Nous proposons dans cet article une méthode permettant d’inférer, du comportement et des choix des diffuseurs, la valeur « concurrentielle » qu’ils accordent à la musique enregistrée et d’obtenir de cette valeur inférée les montants qu’ils devraient verser aux auteurs, compositeurs, interprètes et producteurs au chapitre des droits d’auteur. Nous appliquons la méthode sur des données canadiennes. Le cadre institutionnel de référence nous est fourni par la cause de 2004 devant la Commission du droit d’auteur du Canada relative au tarif applicable à la radio commerciale. Nos résultats montrent qu’une hausse substantielle des paiements pour droits d’auteur s’impose : ces paiements « concurrentiels » devraient être plus du double de ceux que l’industrie versait effectivement au moment des audiences de la cause.copyright valuation, Commercial radio, évaluation des droits d’auteur, radio commerciale
Do CEOs Exercise Their Stock Options Earlier than Other Executives?
This paper looks at the timing chosen by CEOs to exercise their stock options and to sell their shares of stock compared to the timing chosen by other top executives in the firm. We first present a model that predicts when CEOs should exercise their options and/or sell their shares, and when other top managers should. Using a tournament approach we find that other top executives should exercise their stock options later than the CEO. We test this model using an unique data set of Canadian companies from 1993 onward. Our results seem to support the theoretical model as non-CEO executives seem to exercise their stock options about a calendar year later than the CEO. Moreover, non-CEO executive a more likely to exercise when a new CEO has been appointed, confirming our tournament model results. Nous étudions dans cet article le moment choisi par le PDG d'une compagnie pour lever ses options ou vendre ses actions dans la compagnie comparativement au moment choisi par les autres hauts dirigeants de la compagnie. Nous présentons premièrement un modèle théorique de tournoi qui fait des prédictions quant au moment opportun pour le PDG et les autres dirigeants de lever leurs options et/ou de vendre leurs actions dans la compagnie. Nous montrons théoriquement dans un tel modèle de tournoi que les hauts dirigeants devraient lever leurs options après le PDG. Nous testons ce modèle en utilisant une base de données unique de compagnies canadiennes de 1993 à 1999. Nos résultats empiriques semblent supporter notre modèle théorique puisque les hauts dirigeants semblent lever leurs options un an plus tard que le PDG. De plus, les hauts dirigeants semblent plus enclins à lever leurs options lorsqu'un nouveau PDG vient d'être nommé, confirmant ainsi notre modèle de tournoi.CEO and Executive Compensation, Options, Timing of Exercised Options., Contributions volontaires, pertes publiques, risque, ambiguïté, données expérimentales
Catalytic site forms and controls in ATP synthase catalysis
AbstractA suggested minimal scheme for substrate binding by and interconversion of three forms of the catalytic sites of the ATP synthase is presented. Each binding change, that drives simultaneous interchange of the three catalytic site forms, requires a 120° rotation of the γ with respect to the β subunits. The binding of substrate(s) at two catalytic sites is regarded as sufficing for near maximal catalytic rates to be attained. Although three sites do not need to be filled for rapid catalysis, during rapid bisite catalysis some enzyme may be transiently present with three sites filled. Forms with preferential binding for ADP and Pi or for ATP are considered to arise from the transition state and participate in other steps of the catalysis. Intermediate forms and steps that may be involved are evaluated. Experimental evidence for energy-dependent steps and for control of coupling to proton translocation and transition state forms are reviewed. Impact of relevant past data on present understanding of catalytic events is considered. In synthesis a key step is suggested in which proton translocation begins to deform an open site so as to increase the affinity for ADP and Pi, that then bind and pass through the transition state, and yield tightly bound ATP in one binding change. ADP binding appears to be a key parameter controlling rotation during synthesis. In hydrolysis ATP binding to a loose site likely precedes any proton translocation, with proton movement occurring as the tight site form develops. Aspects needing further study are noted. Characteristics of the related MgADP inhibition of the F1 ATPases that have undermined many observations are summarized, and relations of three-site filling to catalysis are assessed
Squeezed Light and Entangled Images from Four-Wave-Mixing in Hot Rubidium Vapor
Entangled multi-spatial-mode fields have interesting applications in quantum
information, such as parallel quantum information protocols, quantum computing,
and quantum imaging. We study the use of a nondegenerate four-wave mixing
process in rubidium vapor at 795 nm to demonstrate generation of
quantum-entangled images. Owing to the lack of an optical resonator cavity, the
four-wave mixing scheme generates inherently multi-spatial-mode output fields.
We have verified the presence of entanglement between the multi-mode beams by
analyzing the amplitude difference and the phase sum noise using a dual
homodyne detection scheme, measuring more than 4 dB of squeezing in both cases.
This paper will discuss the quantum properties of amplifiers based on
four-wave-mixing, along with the multi mode properties of such devices.Comment: 11 pages, 8 figures. SPIE Optics and Photonics 2008 proceeding (San
Diego, CA
Unexpected effect of copper ions on electrochemical impedance behaviour of self-assembled alkylaminethiol monolayer
Effect of copper ions on the electrochemical behaviour of an alkylaminethiol monolayer has been studied by electrochemical impedance spectrosocpy. RAMAN experiment shows the effective adsorption of receptor onto the gold surfaces. The study of Nyquist plot shows that the gold/monolayer/electrolyte interface can be described by a serial combination of two R, CPE electrical circuits. In the presence of increasing amounts of copper, the Nyquist plots at low frequencies were modified showing an increase of the resistance of the second R, CPE electrical circuit. Moreover, this increase of resistance varies linearly with the amounts of copper ions added in solution from 10−8 mol·L−1 to 10−5 mol·L−1
Demonstration of images with negative group velocities
We report the experimental demonstration of the superluminal propagation of
multi-spatial-mode images via four-wave mixing in hot atomic vapor, in which
all spatial sub-regions propagate with negative group velocities. We
investigate the spatial mode properties and temporal reshaping of the fast
light images, and show large relative pulse peak advancements of up to 64% of
the input pulse width. The degree of temporal reshaping is quantified and
increases as the relative pulse peak advancement increases. When optimized for
image quality or pulse advancement, negative group velocities of up to
and , respectively, are
demonstrated when integrating temporally over the entire image. The present
results are applicable to temporal cloaking devices that require strong
manipulation of the dispersion relation, where one can envision temporally
cloaking various spatial regions of an image for different durations.
Additionally, the modes involved in a four-wave mixing process similar to the
present experiment have been shown to exhibit quantum correlations and
entanglement. The results presented here provide insight into how to tailor
experimental tests of the behavior of these quantum correlations and
entanglement in the superluminal regime.Comment: 9 pages, 4 figure
Le rôle du collatéral dans le report des investissements en présence d’asymétries d’information
Cet article étudie les liens potentiels qui peuvent exister entre la disponibilité du collatéral pour les firmes et leurs décisions d’investissement. Nous identifions d’abord sous quelles conditions le collatéral apparaît de façon optimale dans les contrats financiers. Puis, sous ces conditions, nous considérons comment le collatéral, lorsque soumis à des chocs exogènes, peut être la source du report des investissements à une période ultérieure. En particulier, nous démontrons que des chocs permanents au collatéral peuvent causer des changements temporaires dans les décisions d’investissement. Un lien est ainsi créé entre le fonctionnement des marchés financiers et les décisions d’investissement des entreprises.This article studies the potential links between the value of collateral and the investment decisions made by firms. We show that the use of collateral is an endogenous response to the presence of asymmetric information in financial markets. We then show that permanent shocks to the value of collateral can cause firms to temporarily postpone their investments. This creates a link between imperfections in financial markets and investment decisions made by firms
Le rôle du collatéral dans le report des investissements en présence d’asymétries d’information
Cet article étudie les liens potentiels qui peuvent exister entre la disponibilité du collatéral pour les firmes et leurs décisions d’investissement. Nous identifions d’abord sous quelles conditions le collatéral apparaît de façon optimale dans les contrats financiers. Puis, sous ces conditions, nous considérons comment le collatéral, lorsque soumis à des chocs exogènes, peut être la source du report des investissements à une période ultérieure. En particulier, nous démontrons que des chocs permanents au collatéral peuvent causer des changements temporaires dans les décisions d’investissement. Un lien est ainsi créé entre le fonctionnement des marchés financiers et les décisions d’investissement des entreprises.This article studies the potential links between the value of collateral and the investment decisions made by firms. We show that the use of collateral is an endogenous response to the presence of asymmetric information in financial markets. We then show that permanent shocks to the value of collateral can cause firms to temporarily postpone their investments. This creates a link between imperfections in financial markets and investment decisions made by firms
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