Non Cooperatives Stackelberg Networks

Noncooperative network-formation games in oligopolies analyze optimal connection structures that emerge when linking represent the appropriation of cost-reducing one-way externalities. These models reflect situations where one firm access to another firm’s (public or private) information and this last cannot refuse it. What would happen if decisions are sequential? A model of exogenous Stackelberg leadership is developed and first-mover advantages are observed and commented.non cooperative games, network formation strategies, Stackelberg equilibrium.

Compositional Time Series: Past and Present

This survey reviews diverse academic production on compositional dynamic series analysis. Although time dimension of compositional series has been little investigated, this kind of data structure is widely available and utilized in social sciences research. This way, a review of the state-of-the-art on this topic is required for scientist to understand the available options. The review comprehends the analysis of several techniques like autoregresive integrate moving average (ARIMA) analysis, compositional vector autoregression systems (CVAR) and state space techniques but most of these are developed under Bayesian frameworks. As conclusion, this branch of the compositional statistical analysis still requires a lot of advances and updates and, for this same reason, is a fertile field for future research. Social scientists should pay attention to future developments due to the extensive availability of this kind of data structures in socioeconomic databases.compositional data analysis, time series

Connections, Specialization, & Lawsuits: The Influence of Human and Social Capital Formation in the Legal Profession

Legal profession represents a key labor sector whether in politics or business in any developed or underdeveloped country. What resources do lawyers use for matching the demand to their own services’ supply? Private sector lawyers make use of their level of human capital and their social capital for this to be accomplished. This work makes a literature survey focusing on legal profession and their relationships with these capital dimensions. Particular interest is given to the relationship of these capital forms and the effectiveness of professional performance.Human capital, social capital, legal profession

Leyes de valoración de redes

The valuation of a social network is an issue that has been addressed based on simplifying approaches. Various value laws have been stipulated, which are largely atheoretical but have been effectively used to estimate the potential economic value of social network-based firms. This review highlights the various contributions used in the recent literature on networks valuation laws.La valoración de una red social es un tema que ha sido abordado partiendo de enfoques simplificadores. Se han estipulado diversas leyes de valoración, las cuales mayormente son ateóricas pero han sido usadas para efectivamente estimar el potencial de valor económico de una red social. Esta revisión destaca los distintos aportes utilizados en la literatura reciente sobre leyes de valoración de redes

Taxonomía de la red de la élite capitular de Buenos Aires, 1776-1810

We analyze structural properties and visualization of a historical-data-constructed social network of the families with members in the Cabildo (city council) of colonial Buenos Aires. The data was obtained through the review of birth, marriage, and death records kept in various institutions and expanded from online genealogical sources. We find structural properties and visual presentations and also a link centrality analysis that shows that ritual relationship represents an important glue that held together with the network.Analizamos las propiedades estructurales y la visualización de una red social construida por datos históricos de las familias con miembros en el Cabildo (ayuntamiento) de la Buenos Aires colonial. Los datos se obtuvieron a través de la revisión de registros de nacimientos, matrimonios y defunciones mantenidos en varias instituciones y ampliados de fuentes genealógicas en línea. Encontramos propiedades estructurales y presentaciones visuales y también un análisis de centralidad de enlace que muestra que las relaciones rituales representan un pegamento importante que mantuvo unida la red

Popularity in Facebook Pages: What role network structural variables play?

Facebook pages (FP) are meeting points between events and actors in virtual social networks (RSV) of this platform. Companies and events bring together actors that participate through the online expression mechanisms that are enabled, through reactions, tagging, photo posting, liking, comments, etc. These interactions form online contact networks. We propose to investigate structural variables of the networks captured online with structural variables of these networks. We found that various structural variables related to concentration or disconnection between nodes are negatively associated with popularity measured by the number of likes, on the other hand, the most popular FPs associated with the media (radio and news).Facebook pages (FP) are meeting points between events and actors in virtual social networks (RSV) of this platform. Companies and events bring together actors that participate through the online expression mechanisms that are enabled, through reactions, tagging, photo posting, liking, comments, etc. These interactions form online contact networks. We propose to investigate structural variables of the networks captured online with structural variables of these networks. We found that various structural variables related to concentration or disconnection between nodes are negatively associated with popularity measured by the number of likes, on the other hand, the most popular FPs associated with the media (radio and news)

Weekly cookie inflation: A panel data approach

El objetivo de este trabajo es evaluar la dinámica semanal de precios del sector de galletitas en el marco de una economía con inflación moderada, tal como lo es la argentina. Empleando datos de frecuencia semanal, se estiman cinco versiones de la función que relaciona a la variación semanal de los precios de las galletitas con sus posibles determinantes. Cuatro de esas estimaciones han sido obtenidas mediante mínimos cuadrados generalizados (MCG), en tanto que la restante corresponde a una especificación con efectos aleatorios (EA). Se identificaron posibles influencias del nivel de concentración de la oferta, las características de cada producto (tamaño, sabor, tipo), la situación del mercado cambiario, ciertos efectos temporales y las variaciones en los precios de los insumos sobre la dinámica de precios de las galletitas. Sin embargo, solamente los efectos de las variaciones en los precios de los insumos se presentaron robustos. El signo de estos efectos robustos coincide siempre con el esperado, a excepción del caso de la harina de trigoThe objective of this contribution is to evaluate the weekly price dynamics of the biscuit sector in the framework of an economy with moderate inflation, such as Argentina. Using weekly frequency data, five versions of the function that relate cookie price weekly variations with their possible determinants are estimated. Four of these estimates have been obtained using generalized least squares (GLS), while the rest corresponds to a specification with random effects (RE). Possible influences of the supply level concentration, the features of each product (size, flavour and type), the exchange market situation, certain temporary effects and the variations in the prices of inputs on the price dynamics of the cookies are identified. However, only the effects of changes in input prices were robust. The sign of these robust effects always coincides with the expected values, with the exception of the case of wheat flour.Universidad Pablo de Olavid

Cut-offs and response criteria for the Hospital Universitario la Princesa Index (HUPI) and their comparison to widely-used indices of disease activity in rheumatoid arthritis

Objective To estimate cut-off points and to establish response criteria for the Hospital Universitario La Princesa Index (HUPI) in patients with chronic polyarthritis. Methods Two cohorts, one of early arthritis (Princesa Early Arthritis Register Longitudinal PEARL] study) and other of long-term rheumatoid arthritis (Estudio de la Morbilidad y Expresión Clínica de la Artritis Reumatoide EMECAR]) including altogether 1200 patients were used to determine cut-off values for remission, and for low, moderate and high activity through receiver operating curve (ROC) analysis. The areas under ROC (AUC) were compared to those of validated indexes (SDAI, CDAI, DAS28). ROC analysis was also applied to establish minimal and relevant clinical improvement for HUPI. Results The best cut-off points for HUPI are 2, 5 and 9, classifying RA activity as remission if =2, low disease activity if >2 and =5), moderate if >5 and <9 and high if =9. HUPI''s AUC to discriminate between low-moderate activity was 0.909 and between moderate-high activity 0.887. DAS28''s AUCs were 0.887 and 0.846, respectively; both indices had higher accuracy than SDAI (AUCs: 0.832 and 0.756) and CDAI (AUCs: 0.789 and 0.728). HUPI discriminates remission better than DAS28-ESR in early arthritis, but similarly to SDAI. The HUPI cut-off for minimal clinical improvement was established at 2 and for relevant clinical improvement at 4. Response criteria were established based on these cut-off values. Conclusions The cut-offs proposed for HUPI perform adequately in patients with either early or long term arthritis

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Non cooperative Stackelberg network formation

Non-cooperative network formation games in industrial organizations analyze how firms create links. We assume that links portray cost-reducing information and that access to this information is not reciprocal. We study the consequences in terms of profits if one firm can move first in establishing a link. A classic model of exogenous Stackelberg leadership is developed and first-mover advantage is observed