3499 research outputs found
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Coupling News Sentiment with Web Browsing Data Improves Prediction of Intra-Day Price Dynamics
No full textThe new digital revolution of big data is deeply changing our capability of understanding society and forecasting the outcome of many social and economic systems. Unfortunately, information can be very heterogeneous in the importance, relevance, and surprise it conveys, affecting severely the predictive power of semantic and statistical methods. Here we show that the aggregation of web users’ behavior can be elicited to overcome this problem in a hard to predict complex system, namely the financial market. Specifically, our in-sample analysis shows that the combined use of sentiment analysis of news and browsing activity of users of Yahoo! Finance greatly helps forecasting intra-day and daily price changes of a set of 100 highly capitalized US stocks traded in the period 2012–2013. Sentiment analysis or browsing activity when taken alone have very small or no predictive power. Conversely, when considering a news signal where in a given time interval we compute the average sentiment of the clicked news, weighted by the number of clicks, we show that for nearly 50% of the companies such signal Granger-causes hourly price returns. Our result indicates a “wisdom-of-the-crowd” effect that allows to exploit users’ activity to identify and weigh properly the relevant and surprising news, enhancing considerably the forecasting power of the news sentiment
Multiparty Testing Preorders
No full textVariants of the must testing approach have been successfully applied in Service Oriented Computing for analysing the compliance between (contracts exposed by) clients and servers or, more generally, between two peers. It has however been argued that multiparty scenarios call for more permissive notions of compliance because partners usually do not have full coordination capabilities. We propose two new testing preorders, which are obtained by restricting the set of potential observers. For the first preorder, called uncoordinated, we allow only sets of parallel observers that use different parts of the interface of a given service and have no possibility of intercommunication. For the second preorder, that we call independent, we instead rely on parallel observers that perceive as silent all the actions that are not in the interface of interest. We have that the uncoordinated preorder is coarser than the classical must testing preorder and finer than the independent one. We also provide a characterisation in terms of decorated traces for both preorders: the uncoordinated preorder is defined in terms of must-sets and Mazurkiewicz traces while the independent one is described in terms of must-sets and classes of filtered traces that only contain designated visible actions
Bridging or bonding? Preferences for redistribution and social capital in Russia
No full textDoes bridging or bonding social capital matter for redistribution preferences? Existing literature demonstrates causal link between measures of social capital and such preferences but does it mostly for developed countries with good enforcement of formal rules and without a distinction between two completely different types of social capital. We argue that welfare state relies on contributions from an immense number of anonymous citizens, thus attitudes towards strangers, i.e. generalized trust and solidarity should be salient. Using two surveys of about 34,000 and 37,000 Russians we prove this proposition showing the importance of the bridging type but not the bonding one. Instrumenting social capital with education, climate and distance from Moscow we deal with endogeneity concerns. Additionally we claim that connection between social capital and redistribution preferences for less developed countries such as Russia could be similar to developed countries
Harm aversion explains utilitarian choices in moral decision-making in males but not in females
No full textIn recent years, a great deal of research has relied on hypothetical sacrificial dilemmas to investigate decision-making processes involved in pro-social utilitarian choices. Recent evidence, however, has suggested that moral sacrificial choices may actually reflect reduced harm aversion and antisocial dispositions rather than an utilitarian inclination. Here, we used moral dilemmas to confront healthy volunteers with controversial action choices. We measured impulsiveness and venturesomeness personality traits, which have been shown to influence harm aversion, to test their role in utilitarian action and evaluation of moral acceptability. The results of the present study show that, in males, venturesomeness drives engagement in actions and increases moral acceptability. In contrast, in females no effects of venturesomeness were observed on moral action and evaluation. Rather, in females empathetic concern and personal distress, elicited by the vicarious experience of the other’s emotional states, exerted an inhibitory effect on action. Taken together, these findings indicate that the “harm aversion hypothesis” may contribute to explain utilitarian choices in males but not in females. In both genders, no association was observed between impulsiveness and moral action
Social Capital Predicts Happiness Over Time
No full textThe evidence summarized in this chapter documents that GDP is associated with well-being over the business cycle, while this correlation tends to wane over longer periods. Instead, the relationship between social capital and well- being tends to set slowly and to be persistent. This is consistent with both the notion that income is affected by adaptation and social comparisons and, conversely, with the notion that social capital is not affected by these same forces. Moreover, we sum up studies concerning the world-wide most striking cases of the Easterlin paradox, the American, Chinese, and Indian ones. These three countries—amounting to almost half of the world population—exhibit a decline in subjective well-being (SWB), despite a more or less outstanding economic growth in the past few decades. We document that the decline of social capital plays a major role in predicting the decline of happiness in these countries—besides the well-known role of social comparisons. This suggests that the decline of social capital may be a part of the explanation of the Easterlin paradox. Overall, our findings support the view that the basic message of happiness economics should not change, i.e., the centrality of GDP should be reduced. Indeed, social capital—as well as economic growth— can be the target for policies aimed at preserving/fostering it (Helliwell, 2011a; Helliwell, 2011b; Rogers etal., 2011; Bilancini and D’Alessandro, 2012)
Strict Nash Equilibria in Non-Atomic Games with Strict Single Crossing in Players (or Types) and Actions
No full textIn this paper we study games where the space of player types is atomless and payoff functions satisfy the property of strict single crossing in types and actions. Under an additional assumption of quasisupermodularity in actions of payoff functions and mild assumptions on the type space - partially ordered and with sets of uncomparable types having negligible size - and on the action space - lattice, second countable and satisfying a separation property with respect to the ordering of actions - we prove that every Nash equilibrium is essentially strict. Further, by building on McAdams (2003, Theorem 1), we prove existence of a strict Nash equilibrium and an evolutionarily stable strategy in a general class of incomplete information games satisfying strict single crossing in types and actions
«I Cannot Command Winds and Weather»: uno sguardo inglese sul diritto amministrativo globale
No full textGiulio Napolitano, Barbara Marchetti e Lorenzo Casini commentano il
libro «UK, EU and Global Administrative Law. Foundations and Challenges»
di Paul Craig. Gli autori esaminano gli aspetti più rilevanti tra quelli messi in
luce da questo importante volume, con particolare riferimento alle origini del
diritto amministrativo inglese, l’evoluzione del diritto amministrativo europeo,
l’emersione del diritto amministrativo globale
(edited by) Proceedings of the 31st Annual ACM Symposium on Applied Computing, SAC 2016, Special track on service-oriented architectures and programming (SOAP)
No full textThe SOAP track aims at bringing together researchers and practitioners having the common objective of transforming Service-Oriented Programming (SOP) into a mature discipline with both solid scientific foundations and mature software engineering development methodologies supported by dedicated tools. From the foundational point of view, many attempts to use formal methods for specification and verification in this setting have been made. Session correlation, service types, contract theories, and communication patterns are only a few examples of the aspects that have been investigated. Moreover, several formal models based upon automata, Petri nets and algebraic approaches have been developed. However, most of these approaches concentrate only on a few features of service-oriented systems in isolation, and a comprehensive approach is still lacking.
From the engineering point of view, there are open issues at many levels. Among others, at the system design level, both traditional approaches based on UML and approaches taking inspiration from Business Process Modelling, e.g. BPMN, are used. At the composition level, orchestration and choreography are continuously being improved both formally and practically, with an evident need for their integration in the development process. At the description and discovery level, there are two separate communities pushing respectively the semantic approach (like ontologies and OWL) and the syntactic one (like WSDL). In particular, the role of discovery engines and protocols is not clear. In this respect, adopted standards are still missing. UDDI looked to be a good candidate, but it is no longer pushed by the main corporations, and its wide adoption seems difficult. Furthermore, a recent implementation platform, the so-called REST services, is emerging and competing with classic Web Services. Finally, features like Quality of Service, security, and dependability need to be taken seriously into account.
SOAP in particular encouraged submissions on what SOP still needs in order to achieve the above goals.
The PC of SOAP 2016 was formed by:
• Farhad Arbab Leiden University and CWI, Amsterdam, NL
• Luís Barbosa University of Minho, Braga, PT
• Massimo Bartoletti Università di Cagliari, IT
• Maurice H. ter Beek ISTI-CNR, Pisa, IT (co-chair)
• Marcello M. Bersani Politecnico di Milano, IT
• Laura Bocchi University of Kent, UK
• Roberto Bruni Università di Pisa, IT
• Marco Carbone IT University of Copenhagen, DK
• Romain Demangeon Université Pierre et Marie Curie, FR
• Schahram Dustdar Vienna University of Technology, AT
• Alessandra Gorla IMDEA Software Institute, Madrid, ES
• Vasileios Koutavas Trinity College Dublin, IE
• Alberto Lluch Lafuente Technical University of Denmark, DK
• Manuel Mazzara Innopolis University, RU
• Hernán Melgratti University of Buenos Aires, AR (co-chair)
• Nicola Mezzetti University of Trento, IT
• Corrado Moiso Telecom Italia, IT
• Alberto Núñez Universidad Complutense de Madrid, ES
• Jorge A. Perez University of Groningen, NL
• Gustavo Petri Purdue University, USA
• António Ravara New University of Lisbon, PT
• Steve Ross-Talbot Cognizant Technology Solutions, UK
• Gwen Salaün Inria Grenoble - Rhône-Alpes, FR
• Francesco Tiezzi Università di Camerino, IT
• Hugo Torres Vieira IMT Lucca, IT (co-chair)
• Emilio Tuosto University of Leicester, UK
• Massimo Vecchio Università degli Studi eCampus, IT
• Peter Wong Travelex, UK
• Yongluan Zhou University of Southern Denmark, DK
SOAP 2016 received a total of 16 submissions. Each submission was reviewed by at least 4 PC members, the vast majority even by 5 PC members. All papers were subject to an animated general discussion among the PC members (with over 100 posts in the message boards). In the end, the PC decided to select only the following four papers for an oral presentation at the conference (an acceptance rate of 25%):
• JxActinium: a runtime manager for secure REST-ful COAP applications working over JXTA by Filippo Battaglia, Giancarlo Iannizzotto, and Lucia Lo Bello
• Improving QoS Delivered by WS-BPEL Scenario Adaptation through Service Execution Parallelization by Dionisis Margaris, Costas Vassilakis, and Panagiotis Georgiadis
• QoS-aware Adaptation for Complex Event Service by Feng Gao, Muhammad Ali, Edward Curry, and Alessandra Mileo
• Service functional testing automation with intelligent scheduling and planning by Lom Messan Hillah, Ariele-Paolo Maesano, Libero Maesano, Fabio De Rosa, Fabrice Kordon, and Pierre-Henri Wuillemin
We would like to thank the PC members, and a few external reviewers, for their detailed reports and the stimulating discussions during the reviewing phase; the authors of submitted papers, the session chairs and the attendees, for contributing to the success of the event; the providers of the START system, which was used to manage the submissions; and in particular all the organizers of SAC 2016, for their invitation to organize this track and for all their excellent assistance and support
«The Loneliness of the Comparative Lawyer». In memoria di John Henry Merryman (1920-2015)
No full textA novel algorithm for the calculation of physical and biological irradiation quantities in scanned ion beam therapy: the beamlet superposition approach
No full textThe calculation algorithm of a modern treatment planning system for ion-beam radiotherapy should ideally be able to deal with different ion species (e.g. protons and carbon ions), to provide relative biological effectiveness (RBE) evaluations and to describe different beam lines. In this work we propose a new approach for ion irradiation outcomes computations, the beamlet superposition (BS) model, which satisfies these requirements. This model applies and extends the concepts of previous fluence-weighted pencil-beam algorithms to quantities of radiobiological interest other than dose, i.e. RBE- and LET-related quantities. It describes an ion beam through a beam-line specific, weighted superposition of universal beamlets. The universal physical and radiobiological irradiation effect of the beamlets on a representative set of water-like tissues is evaluated once, coupling the per-track information derived from FLUKA Monte Carlo simulations with the radiobiological effectiveness provided by the microdosimetric kinetic model and the local effect model. Thanks to an extension of the superposition concept, the beamlet irradiation action superposition is applicable for the evaluation of dose, RBE and LET distributions. The weight function for the beamlets superposition is derived from the beam phase space density at the patient entrance. A general beam model commissioning procedure is proposed, which has successfully been tested on the CNAO beam line. The BS model provides the evaluation of different irradiation quantities for different ions, the adaptability permitted by weight functions and the evaluation speed of analitical approaches. Benchmarking plans in simple geometries and clinical plans are shown to demonstrate the model capabilities