1,720,957 research outputs found
Complex dynamics associated with the appearance/disappearance of invariant closed curves
In this paper we study some global bifurcations arising in a heterogeneous financial model with fundamentalists and imitators. Such bifurcations which cause the appearance and disappearance of closed invariant curves (attracting or repelling) involve the stable and unstable sets of a saddle cycle with consequent changes in their dynamic behavior. Numerical investigations show that the transition between two qualitatively different regimes are characterized by the occurrence of homoclinic tangles with chaotic
dynamics
Agglomeration dynamics and first nature asymmetries
The standard footloose capital (FC) model, as well as the discrete time version, assumes that all capital units are internationally mobile between two regions. In this paper, we assume that in one of the two regions some of the blueprints/capital units may be immobile because their utilization requires some locally specific natural resource (first nature advantage). Mobile blueprints, instead, can be utilized in both regions. We focus on this asymmetric distribution of immobile firms/capital units, labeled first nature firms. The central question of our paper is how the existence of first nature asymmetry affects agglomerative processes framed in discrete time. This modification of the FC model leads to a one dimensional piecewise smooth map for which we show analytically that border collision bifurcations are pervasive and (even asymmetric) multistability is possible
An assessment of the implementation of the European tourism indicator system for sustainable destinations in Italy
The European Tourism Indicators System (ETIS) is a product of the European Union (EU) Sustainable Development Strategy, which was formulated with the objectives of promoting economic prosperity, social equity, cohesion, and environmental protection. In this paper, we present an analysis of the results of the implementation of the ETIS during the period 2013-2016, in the Italian tourist destination of South Sardinia. While the implementation of ETIS constitutes a significant advancement in Italy, and more widely in Europe, our findings reveal that an adaptive management approach is necessary for achieving the anticipated objectives and adapting these standardized indicators to different territorial contexts. Difficulties were encountered in both data collection and stakeholders' involvement in the implementation process. Insufficient knowledge, and familiarity with the complex technical aspects of the indicator toolkit among primary stakeholders, was another constraint associated with its implementation. We believe that the findings of this analysis can provide guidelines and inputs for other European countries and tourist destinations that are currently in the process of implementing the ETIS toolkit or similar methodologies. In particular, the pioneering sustainable tourism performance measurement system (STPMS) can be adapted to meet local needs
Border Collision Bifurcations in a Footloose Capital Model with First Nature Firms
Piecewise smooth map, Border collision bifurcations, New Economic Geography, Footloose Capital models,
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
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
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