Three-feature model to reproduce the topology of citation networks and the effects from authors' visibility on their h-index

Various factors are believed to govern the selection of references in citation networks, but a precise, quantitative determination of their importance has remained elusive. In this paper, we show that three factors can account for the referencing pattern of citation networks for two topics, namely "graphenes" and "complex networks", thus allowing one to reproduce the topological features of the networks built with papers being the nodes and the edges established by citations. The most relevant factor was content similarity, while the other two - in-degree (i.e. citation counts) and {age of publication} had varying importance depending on the topic studied. This dependence indicates that additional factors could play a role. Indeed, by intuition one should expect the reputation (or visibility) of authors and/or institutions to affect the referencing pattern, and this is only indirectly considered via the in-degree that should correlate with such reputation. Because information on reputation is not readily available, we simulated its effect on artificial citation networks considering two communities with distinct fitness (visibility) parameters. One community was assumed to have twice the fitness value of the other, which amounts to a double probability for a paper being cited. While the h-index for authors in the community with larger fitness evolved with time with slightly higher values than for the control network (no fitness considered), a drastic effect was noted for the community with smaller fitness

Da perceção subjetiva de discriminação à experiência de vitimação em contexto de vulnerabilidade socioeconómica: uma abordagem narrativa

Orientação: Joana Maria Barreto Ramos de Almeida CabralO fenómeno de discriminação socioeconómica é uma forma de discriminação cada vez mais presente nas sociedades contemporâneas. O crescente acentuar da polarização socioeconómica entre uns e outros, num mundo cada vez mais competitivo, menos cooperante, tem favorecido o aumento acentuado da exclusão social. No presente estudo procurou-se compreender a forma como a experiência de vitimação decorrente da perceção de discriminação socioeconómica é subjetivamente construída em contexto de vulnerabilidade socioeconómica, à luz do modelo ecológico e das abordagens narrativas. O estudo envolveu 4 adultos, 3 do sexo masculino e 1 do feminino, com os quais se procedeu à aplicação de uma entrevista semi-estruturada com base na qual se procurou avaliar o impacto do tratamento discriminatório recebido no contacto de proximidade do indivíduo com as várias esferas sociais, bem como avaliar a perceção individual da qualidade de vida em contexto de vulnerabilidade socioeconómica. De acordo com a literatura, para a compreensão da formação das identidades sociais e das representações sociais por parte dos indivíduos, há que ter em conta os fatores individuais, sociais e culturais que rodeiam os indivíduos, no tempo e no espaço. Neste estudo propusemo-nos perceber a perceção que os indivíduos têm sobre a sua realidade-condição e o sentido que a mesma assume para eles, e compreender as atitudes e comportamentos que apresentam perante situações de discriminação socioeconómica. Os resultados deste estudo ajudam a perceber a intersubjetividade inerente aos conceitos em estudo, nomeadamente na relação como são percecionados, significados e operacionalizados pelos participantes. Os participantes mencionam alterações nas relações interpessoais e intrapessoais decorrentes da exclusão social. Os participantes apontam alterações de ordem estrutural, nomeadamente de facilitação ao acesso a serviços de apoio instrumental por parte dos mais vulneráveis socioeconomicamente, bem como alterações de caráter individual e educacional dos excluídos e de quem os exclui.The phenomenon of socio-economic discrimination is a form of discrimination that is increasingly present in contemporary societies. The growing accentuation of socio-economic polarization between the two, in an increasingly competitive, less cooperative world, has favored a sharp increase in social exclusion. In the present study we tried to understand how the experience of victimization resulting from the perception of socio-economic discrimination is subjectively constructed in a context of socio-economic vulnerability, in light of the ecological model and narrative approaches. The study involved 4 adults, 3 males and 1 females, with whom a semistructured interview was carried out, based on which the impact of the discriminatory treatment received in the proximity contact of the individual with the various social spheres, as well as evaluating the individual perception of quality of life in a context of socioeconomic vulnerability. According to the literature, to understand the formation of social identities and social representations by individuals, it is necessary to take into account the individual, social and cultural factors that surround individuals in time and space. In this study we proposed to perceive the individuals' perception of their reality-condition and the meaning it assumes for them, and to understand the attitudes and behaviors that they present in situations of socioeconomic discrimination. The results of this study help to understand the intersubjectivity inherent to the concepts under study, namely in the relation how they are perceived, meaning and operationalized by the participants. Participants mention changes in the interpersonal and intrapersonal relationships resulting from social exclusion. The participants point out structural changes, such as facilitating access to instrumental support services by the most vulnerable socioeconomically, as well as changes in the individual and educational character of the excluded and those who exclude them

Structure-semantics interplay in complex networks and its effects on the predictability of similarity in texts

There are different ways to define similarity for grouping similar texts into clusters, as the concept of similarity may depend on the purpose of the task. For instance, in topic extraction similar texts mean those within the same semantic field, whereas in author recognition stylistic features should be considered. In this study, we introduce ways to classify texts employing concepts of complex networks, which may be able to capture syntactic, semantic and even pragmatic features. The interplay between the various metrics of the complex networks is analyzed with three applications, namely identification of machine translation (MT) systems, evaluation of quality of machine translated texts and authorship recognition. We shall show that topological features of the networks representing texts can enhance the ability to identify MT systems in particular cases. For evaluating the quality of MT texts, on the other hand, high correlation was obtained with methods capable of capturing the semantics. This was expected because the golden standards used are themselves based on word co-occurrence. Notwithstanding, the Katz similarity, which involves semantic and structure in the comparison of texts, achieved the highest correlation with the NIST measurement, indicating that in some cases the combination of both approaches can improve the ability to quantify quality in MT. In authorship recognition, again the topological features were relevant in some contexts, though for the books and authors analyzed good results were obtained with semantic features as well. Because hybrid approaches encompassing semantic and topological features have not been extensively used, we believe that the methodology proposed here may be useful to enhance text classification considerably, as it combines well-established strategies