1,721,154 research outputs found
A game-theoretic approach for reliability evaluation of public transportation transfers with stochastic features
No full textA game-theoretic approach based on the framework of transferable-utility cooperative games is developed to assess the reliability of transfer nodes in public transportation networks in the case of stochastic transfer times. A cooperative game is defined, whose model takes into account the public transportation system, the travel times, the transfers and the associated stochastic transfer times, and the users’ demand. The transfer stops are modeled as the players of such a game, and the Shapley value – a solution concept in cooperative game theory – is used to identify their centrality and relative importance. Theoretical properties of the model are analyzed. A two-level Monte Carlo approximation of the vector of Shapley values associated with the nodes is introduced, which is efficient and able to take into account the stochastic features of the transportation network. The performance of the algorithm is investigated, together with that of its distributed computing variation. The usefulness of the proposed approach for planners and policy makers is shown with a simple example and on a case study from the public transportation network of Auckland, New Zealand
Public Transport Transfers Assessment via Transferable Utility Games and Shapley Value Approximation
No full textThe importance of transfer points in public transport networks is estimated by exploiting an approach based on transferable utility cooperative games, which integrates the network topology and the demands. Transfer points are defined as clusters of nearby stops, from which it is easily possible to switch between routes. The methodology is based on a solution concept from cooperative game theory, known as Shapley value. A special formulation of the game is developed for public transport networks with an emphasis on transfers. Based on such a game, the Shapley value is evaluated as an attribute of each transfer point to measure its relative importance: the greater the associated value, the larger the relevance. Due to the computational requirements of the Shapley value calculation for large-size networks, a Monte Carlo approximation is investigated and adopted. A case study of a real-world network is presented to demonstrate the model’s viability
Influencia de los cuentos de hadas y novelas de fantasía en la construcción psíquica del sujeto
Full text linkCon el presente trabajo se procura esclarecer las distintas formas en que operan los cuentos de hadas y las novelas de fantasía, para influenciar en los distintos procesos que dan lugar a la construcción psíquica del sujeto; favoreciendo a su vez, el desarrollo “normal” (no patológico) de los niños y los adolescentes. En virtud de lo cual, se realiza un recorrido tanto por las conceptualizaciones freudianas, y post-freudianas, referentes a la construcción psíquica del sujeto (pulsiones, segunda tópica del aparato psíquico, y Complejo de Edipo), como por las teorías concernientes a las particularidades de la organización psíquica del niño y del adolescente. Siendo este, un trayecto necesario para vincular los diversos elementos presentes en los cuentos de hadas y las novelas literarias, con el proceso de construcción psíquica, y el desarrollo normal de los niños y los adolescentes. Así, tras realizar un análisis psicoanalítico de las historias más cercanas al conocimiento popular de los ecuatorianos, se concluye que estas narraciones tienen la capacidad de atenuar el dominio del Ello, fortalecer el Yo, edificar un Superyó efectivo (no opresivo), ofrecer nuevas “verdades” respecto a uno mismo y los demás, entre otros elementos de igual relevancia para la construcción psíquica del sujeto. De modo que, se instauran a los cuentos de hadas y las novelas de fantasía como valiosos recursos de la vida cotidiana
Influencia de los cuentos de hadas y novelas de fantasía en la construcción psíquica del sujeto
No full textCon el presente trabajo se procura esclarecer las distintas formas en que operan los cuentos de hadas y las novelas de fantasía, para influenciar en los distintos procesos que dan lugar a la construcción psíquica del sujeto; favoreciendo a su vez, el desarrollo “normal” (no patológico) de los niños y los adolescentes. En virtud de lo cual, se realiza un recorrido tanto por las conceptualizaciones freudianas, y post-freudianas, referentes a la construcción psíquica del sujeto (pulsiones, segunda tópica del aparato psíquico, y Complejo de Edipo), como por las teorías concernientes a las particularidades de la organización psíquica del niño y del adolescente. Siendo este, un trayecto necesario para vincular los diversos elementos presentes en los cuentos de hadas y las novelas literarias, con el proceso de construcción psíquica, y el desarrollo normal de los niños y los adolescentes. Así, tras realizar un análisis psicoanalítico de las historias más cercanas al conocimiento popular de los ecuatorianos, se concluye que estas narraciones tienen la capacidad de atenuar el dominio del Ello, fortalecer el Yo, edificar un Superyó efectivo (no opresivo), ofrecer nuevas “verdades” respecto a uno mismo y los demás, entre otros elementos de igual relevancia para la construcción psíquica del sujeto. De modo que, se instauran a los cuentos de hadas y las novelas de fantasía como valiosos recursos de la vida cotidiana
On the Approximation of the Shapley Value via Machine Learning in Transportation Network Cooperative Games
No full textThe Shapley value, a well-established concept in cooperative game theory, serves as a metric for assessing the significance of each player in a transferable utility game. Recently, it has found application in gauging the importance of individual nodes or arcs within a network. However, in this context, the exact evaluation of the Shapley value is often computationally expensive, particularly in the case of extensive networks. This study delves into the challenge of approximating the Shapley value in a transferable utility game defined on a network, wherein the characteristics of the network are parameterized by a variable of interest (e.g., the traffic demand). We examine the smoothness of the Shapley value with respect to this parameter and leverage such smoothness to theoretically justify the adoption of machine-learning techniques for its approximate computation. Additionally, we present potential extensions for further research in this area
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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