1,720,981 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Essays on transition challenges for alternative propulsion vehicles and transportation systems
Get PDFThesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, 2006.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references.Technology transitions require the formation of a self-sustaining market through alignment of consumers' interests, producers' capabilities, infrastructure development, and regulations. In this research I develop a broad behavioral dynamic model of the prospective transition to alternative fuel vehicles. In Essay one I focus on the premise that automobile purchase decisions are strongly shaped by cultural norms, personal experience, and social interactions. To capture these factors, I examine important social processes conditioning alternative vehicle diffusion, including the generation of consumer awareness through feedback from driving experience, word of mouth and marketing. Through analysis of a simulation model I demonstrate the existence of a critical threshold for the sustained adoption of alternative technologies, and show how the threshold depends on behavioral, economic and physical system parameters. Word-of-mouth from those not driving an alternative vehicle is important in stimulating diffusion. Further, I show that marketing and subsidies for alternatives must remain in place for long periods for diffusion to become self-sustaining.(cont.) Results are supported with an analysis of the transition to the horseless carriage at the turn of the 19th century. In the second Essay I explore the co-evolutionary interdependence between alternative fuel vehicle demand and the requisite refueling infrastructure. The analysis is based on a dynamic behavioral model with an explicit spatial structure. I find, first, a bi-stable, low demand equilibrium with urban adoption clusters. Further, the diffusion of more fuel efficient vehicles, optimal for the long run, is less likely to succeed, illustrating the existence of trade-offs between the goals of the early stage transition, and those of the long-run equilibrium. Several other feedbacks that significantly influence dynamics including, supply and demand, and supply-coordination behaviors, are discussed. In Essay three I examine how technology learning and spillovers impact technology trajectories of competing incumbents - hybrid and radical entrants. I develop a technology lifecycle model, with an emphasis on technology heterogeneity. In the model, spillovers can flow to the market leader and can be asymmetric across technologies. find that the existence of learning and spillover dynamics greatly increases path dependence. Interaction effects with other feedbacks, such as scale economies, are very strong. Further, superior radical technologies may fail, even when introduced simultaneously with inferior hybrid technologies.(cont.) I find that the existence of learning and spillover dynamics greatly increases path dependence. Interaction effects with other feedbacks, such as scale economies, are very strong. Further, superior radical technologies may fail, even when introduced simultaneously with inferior hybrid technologies.by Jeroen J.R. Struben.Ph.D
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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
The Diffusion of Complex Market Technologies: Multifaceted Dynamics for Alternative Fuel Vehicles
Get PDFThis paper develops initial steps towards a framework for understanding factors that condition success and failure of complex market technologies. Dynamics of such technologies are conditioned by coevolutionary processes including the development of the installed base, consumer behavior, technologies, complementarities and interlinked supply chains. This paper analyzes diffusion patterns, including failures and successes, of alternative transportation fuel (ATF) and vehicle introductions, natural gas in New Zealand and Argentina, and ethanol in Brazil. I analyze the diffusion patterns of retrospective AFV introductions, failures and successes, through a behavioral dynamic simulation model. I characterize technology diffusion as a process of market formation which requires overcoming a period of fragility. During such a period at least one of the mechanisms conditioning its diffusion works against further spreading. Aggressive, simple strategies to overcome thresholds tend to fail. However, high potential strategies involve policy portfolios that are sustained, synchronized across multiple types of decision makers, and dynamic. Further, the efforts and their duration required to overcome this stage are strongly influenced by institutional and historical contexts. More broadly, the findings provide the groundwork for a framework to analyze processes of market formation for complex technologies. Such a framework involves capturing the fundamental mechanisms cutting across inter-organizational fields, but also includes important system-physiological aspects. Within this framework the traditional S-shaped diffusion curve is a special case with ex-ante usefulness confined to conditions of low market complexity and favorable institutional conditions. We discuss implications for policy and strategy
Trust dynamics during early alliance operation : the role of partner engagement
No full textCoopetitive endeavors offer valuable strategic options for firms. Yet, many of them are failure-prone as partners must balance collective and private interest. While interpartner trust is considered central for alliance success, paradoxically, the role and dynamics of trust is still not understood. We synthesize a computational model, capturing relational dynamics of an alliance, encompassing coevolution of trust, partner contributions, and (relative) alliance interactions. Analyzing alliance dynamics using simulation we find and explore a tipping boundary, separating a regime of alliance failure and success. We identify implications for collaborative (aspirations) and private strategies (openness). Our analyses reveal that strategies informed by a static mental model of partner trust, contributions, and openness tend to yield subpar alliance results and hidden failure-risk. We discuss implications for management theory
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