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    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used

    Local-to-Global in Multi-Agent Systems

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    The thesis presents performance analysis and simulation results for algorithms that compute global functions out of local interactions on multi-agent systems. We focus on optimization problems; this is because many problems can be formulated in terms of designing algorithms which optimize some global function subject to local constraints. We model the environment as an adversary of the system. The environment is able to attack the system, modifying the system in arbitrary ways: some agents and/or communication links can be disabled. Computations proceed by opportunistically employing the resources available at each point, progressing rapidly when more resources are available and slowing down when resources become unavailable. We investigate and compare two techniques. In the first one, each sub-system (which we call group) behaves like a centralized system, i.e., it solves its specific optimization sub-problem by applying a central algorithm. We investigate this technique, called self-similarity, showing examples where it works and where it fails, and carry out performance analysis on some problems. Then, we introduce a second technique which is completely decentralized but synchronous: agents simultaneously makes a local update to their current estimates of some true parameter using the estimates of their adjacents. We prove the correctness of this technique on some specific problems by applying tools from distributed systems (variant functions) and control theory (equilibrium points of a dynamical system).</p

    Systematic Design and Formal Verification of Multi-Agent Systems

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    This thesis presents methodologies for verifying the correctness of multi-agent systems operating in hostile environments. Verification of these systems is challenging because of their inherent concurrency and unreliable communication medium. The problem is exacerbated if the model representing the multi-agent system includes infinite or uncountable data types. We first consider message-passing multi-agent systems operating over an unreliable communication medium. We assume that messages in transit may be lost, delayed or received out-of-order. We present conditions on the system that reduce the design and verification of a message-passing system to the design and verification of the corresponding shared-state system operating in a friendly environment. Our conditions can be applied both to discrete and continuous agent trajectories. We apply our results to verify a general class of multi-agent system whose goal is solving a system of linear equations. We discuss this class in detail and show that mobile robot linear pattern-formation schemes are instances of this class. In these protocols, the goal of the team of robots is to reach a given pattern formation. We present a framework that allows verification of message-passing systems operating over an unreliable communication medium. This framework is implemented as a library of PVS theorem prover meta-theories and is built on top of the timed automata framework. We discuss the applicability of this tool. As an example, we automatically check correctness of the mobile robot linear pattern formation protocols. We conclude with an analysis of the verification of multi-agent systems operating in hostile environments. Under these more general assumptions, we derive conditions on the agents' protocols and properties of the environment that ensure bounded steady-state system error. We apply these results to message-passing multi-agent systems that allow for lost, delayed, received out-of-order or forged messages, and to multi-agent systems whose goal is tracking time-varying quantities. We show that pattern formation schemes are robust to leaders dynamics, i.e., in these schemes, followers eventually form the pattern defined by the new positions of the leaders.</p
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