A feature selection method based on Shapley values robust to concept shift in regression

Feature selection is one of the most relevant processes in any methodology for creating a statistical learning model. Generally, existing algorithms establish some criterion to select the most influential variables, discarding those that do not contribute any relevant information to the model. This methodology makes sense in a classical static situation where the joint distribution of the data does not vary over time. However, when dealing with real data, it is common to encounter the problem of the dataset shift and, specifically, changes in the relationships between variables (concept shift). In this case, the influence of a variable cannot be the only indicator of its quality as a regressor of the model, since the relationship learned in the traning phase may not correspond to the current situation. Thus, we propose a new feature selection methodology for regression problems that takes this fact into account, using Shapley values to study the effect that each variable has on the predictions. Five examples are analysed: four correspond to typical situations where the method matches the state of the art and one example related to electricity price forecasting where a concept shift phenomenon has occurred in the Iberian market. In this case the proposed algorithm improves the results significantly

Evaluación Intermedia de un proyecto de mediación escolar en Portugal=Avaliaçao Intermédia de um projecto de mediaçao escolar em Portugal

En este artículo se describe la investigación realizada en una escuela portuguesa. Se trató de una evaluación complementaria al proceso de auto-evaluación existente y referente a tres dimensiones consideradas esenciales para la toma de decisiones sobre el futuro del proyecto: pertinencia, eficacia y eficiencia. Se utilizó una metodología mixta, con el respaldo de un paradigma ecléctico, sobre la base de un estudio de caso simple de subtipo anidado. Fueran elegidas fuentes documentales y entrevistas en profundidad a informantes privilegiados; la investigación se basó en la análisis documental y de contenido, estadística descriptiva y un test no paramétrico de chi - cuadrado para testar la independencia entre la expulsión y el fracaso escolar.___________________________________________O presente artigo descreve a investigação levada a cabo numa escola portuguesaTratou-se de uma avaliação intermédia, complementar ao processo de auto-avaliação e referente a três dimensões consideradas essenciais para a tomada de decisões quanto ao futuro do projecto: relevância, eficácia e eficiência. Foi utilizada uma metodologia mista, sustentada por um paradigma eclético, assente num estudo de caso simples de subtipo aninhado. Optou-se pelo recurso a fontes documentais e entrevistas em profundidade a informadores privilegiados; a investigação foi efectuada com base na análise documental e de conteúdo, estatística descritiva e um teste não paramétrico qui - quadrado para testar a independência entre expulsão e insucesso escolar

Trajectory Based Market Models: Evaluation of Minmax Price Bounds

The paper studies sub and super-replication price bounds for contingent claims defined on general trajectory based market models. No prior probabilistic or topological assumptions are placed on the trajectory space which is of unrestricted cardinality. For a given option, there exists an interval bounding the set of possible fair prices; such interval exists under more general conditions than the usual no-arbitrage requirement. The paper develops a backward recursive method to evaluate the option bounds together with the associated hedging strategies; the global minmax optimization, defining the price interval, is reduced to a local minmax optimization via dynamic programming. Trajectory sets are introduced for which existing probabilistic and non-probabilistic market models are nested as particular cases. Several examples are presented, the effect of the presence of arbitrage on the price bounds is illustrated.Fil: Degano, Iván Leonardo. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Sebastián E. Ferrando. Ryerson University; CanadáFil: Alfredo L, González. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentin

Regulon-Specific Control of Transcription Elongation across the Yeast Genome

Transcription elongation by RNA polymerase II was often considered an invariant non-regulated process. However, genome-wide studies have shown that transcriptional pausing during elongation is a frequent phenomenon in tightly-regulated metazoan genes. Using a combination of ChIP-on-chip and genomic run-on approaches, we found that the proportion of transcriptionally active RNA polymerase II (active versus total) present throughout the yeast genome is characteristic of some functional gene classes, like those related to ribosomes and mitochondria. This proportion also responds to regulatory stimuli mediated by protein kinase A and, in relation to cytosolic ribosomal-protein genes, it is mediated by the silencing domain of Rap1. We found that this inactive form of RNA polymerase II, which accumulates along the full length of ribosomal protein genes, is phosphorylated in the Ser5 residue of the CTD, but is hypophosphorylated in Ser2. Using the same experimental approach, we show that the in vivo–depletion of FACT, a chromatin-related elongation factor, also produces a regulon-specific effect on the expression of the yeast genome. This work demonstrates that the regulation of transcription elongation is a widespread, gene class–dependent phenomenon that also affects housekeeping genes

Nested species-rich networks of scavenging vertebrates support high levels of interspecific competition

Disentangling the processes that shape the organization of ecological assemblages and its implications for species coexistence is one of the foremost challenges of ecology. Although insightful advances have recently related community composition and structure with species coexistence in mutualistic and antagonistic networks, little is known regarding other species assemblages, such as those of scavengers exploiting carrion. Here we studied seven assemblages of scavengers feeding on ungulate carcasses in mainland Spain. We used dynamical models to investigate if community composition, species richness and structure (nestedness) affect species coexistence at carcasses. Scavenging networks showed a nested pattern in sites where highly efficient, obligate scavengers (i.e., vultures) were present and a non- nested pattern everywhere else. Griffon Vulture ( Gyps fulvus ) and certain meso- facultative mammalian scavengers (i.e., red fox, Vulpes vulpes, and stone marten, Martes foina ) were the main species contributing to nestedness. Assemblages with vultures were also the richest ones in species. Nested species- rich assemblages with vulture presence were associated with high carcass consumption rates, indicating higher interspecific competition at the local scale. However, the proportion of species stopping the consumption of carrion (as derived from the competitive dynamic model) stabilized at high richness and nestedness levels. This suggests that high species richness and nestedness may characterize scavenging networks that are robust to high levels of interspecific competition for carrion. Some facilitative interactions driven by vultures and major facultative scavengers could be behind these observations. Our findings are relevant for understanding species' coexistence in highly competitive systemsE. Sebastián- González and P. R. Guimarães benefited from FAPESP Research Foundation grants numbers 2011/17968- 2 and 2009/054422- 8, respectively; E. Sebastián- González is currently funded under the NSF grant NSF Award #1345247, M. Moleón by a postdoctoral grant from the Spanish Ministry of Education (Plan Nacional de I+D+I 2008- 2011), J. P. Gibert by an Other Fellowship and SBS Special Funds (U. of N.), and P. Mateo-Tomás by a postdoctoral grant of the Junta de Comunidades de Castilla-La Mancha and Fondo Social Europeo. The study was supported by the Spanish Ministry of Science and Innovation through projects 23/2007 ICTS- RBD, CGL2009- 12753- C02- 02, and CGL2012- 40013- C02- 02, FEDER funds, the Generalitat Valenciana through project ACOMP/2012/147, and the Junta de Andalucía through project RNM- 192

Nested species- rich networks of scavenging vertebrates support high levels of interspecific competition.

Disentangling the processes that shape the organization of ecological assemblages and its implications for species coexistence is one of the foremost challenges of ecology. Although insightful advances have recently related community composition and structure with species coexistence in mutualistic and antagonistic networks, little is known regarding other species assemblages, such as those of scavengers exploiting carrion. Here we studied seven assemblages of scavengers feeding on ungulate carcasses in mainland Spain. We used dynamical models to investigate if community composition, species richness and structure (nestedness) affect species coexistence at carcasses. Scavenging networks showed a nested pattern in sites where highly efficient, obligate scavengers (i.e., vultures) were present and a non- nested pattern everywhere else. Griffon Vulture ( Gyps fulvus ) and certain meso- facultative mammalian scavengers (i.e., red fox, Vulpes vulpes, and stone marten, Martes foina ) were the main species contributing to nestedness. Assemblages with vultures were also the richest ones in species. Nested species- rich assemblages with vulture presence were associated with high carcass consumption rates, indicating higher interspecific competition at the local scale. However, the proportion of species stopping the consumption of carrion (as derived from the competitive dynamic model) stabilized at high richness and nestedness levels. This suggests that high species richness and nestedness may characterize scavenging networks that are robust to high levels of interspecific competition for carrion. Some facilitative interactions driven by vultures and major facultative scavengers could be behind these observations. Our findings are relevant for understanding species' coexistence in highly competitive systems

RECARGA GESTIONADA DE ACUÍFEROS: MULTIFUNCIONALIDAD EN LA ZONA REGABLE DE SANTIUSTE

[ES] Los dispositivos de recarga gestionada del acuífero de Santiuste (Segovia) dentro de la masa subterránea de Los Arenales llevan en funcionamiento desde 2002. Durante este tiempo se han realizado ampliaciones y modificaciones que han permitido pasar de un sistema puramente hidrogeológico para uso de riego a un dispositivo de gran flexibilidad y creciente multifuncionalidad. En este artículo se muestran las funciones que cumplen los diferentes dispositivos, incidiendo fundamentalmente en los factores ambientales que no aunque no formaban parte del planteamiento original han ganado protagonismo con la evolución del proyecto y su funcionamiento.Este artículo ha sido redactado por miembros del equipo del Grupo Tragsa del proyecto europeo MARSOL (Demostrating Managed Aquifer Recharge as a solution to water scarcity and drought) (WP5), con el apoyo de la European Commission, convocatoria Water Inno-demo (FP 7) con Grant Agreement: GA 619120.Fernández Escalante, E.; González Herrarte, F.; San Sebastián Sauto, J. (2015). RECARGA GESTIONADA DE ACUÍFEROS: MULTIFUNCIONALIDAD EN LA ZONA REGABLE DE SANTIUSTE. En XXXIII CONGRESO NACIONAL DE RIEGOS. Valencia 16-18 junio de 2015. Editorial Universitat Politècnica de València. https://doi.org/10.4995/CNRiegos.2015.1445OC

Efectos de la densidad de siembra sobre Chenopodium quinoa (quinoa). Incidencia sobre variables morfológicas y rendimiento de grano en la variedad CICA cultivada en Amaicha del Valle (Tucumán, Argentina)

El cultivo de la quinoa ha comenzado a extenderse en el Noroeste Argentino (NOA) y en especial en los Valles Calchaquíes (valles de altura ubicados en el Noroeste de Argentina). La variedad más utilizada es CICA, originaria del Perú, que fuera obtenida a partir de otra denominada Amarilla de Maranganí. Sin embar- go, no se han encontrado antecedentes que expliquen la preferencia de esta variedad sobre otras. Para contribuir al conocimiento del manejo agronómico de esta variedad se estudió el efecto de la densidad de siembra sobre la morfología y particularmente sobre el rendimiento en granos. Las experiencias se realizaron en una localidad de los Valles Calchaquíes (Amaicha del Valle, Tucumán, Argentina) a 1.995 m sobre el nivel del mar. Los métodos utilizados para la siembra fueron por golpe, realizado manualmente (“CGo”, CICA separadas) y a chorri- llo, con maquina sembradora (“CCh”, CICA juntas). Con éstos se lograron densidades de plan- tas diferentes: 4,2 y 27,9 plantas/metro lineal respectivamente. Tanto la altura de las plan- tas, diámetro de tallo, área foliar específica (AFE), nitrógeno y fósforo foliar y el rendimiento en granos (kg/ha) fue mayor en el primer tratamiento. El análisis de las clases diamétricas de los granos obtenidos reveló que ambos tratamientos producen casi un 65% de granos cuyo diámetro es ≥ 1,41 mm. Sin embargo, en el tratamiento “CGo” aumenta la proporción de granos cuyos diámetros son ≥ a 1,68 mm. Este último dato es importante pues los granos con mayor diámetro tienen mayor aceptación en los mercados. En general, el rendi- miento en granos fue de 5.389 kg/ha y 3.049 kg/ha para los tratamientos “CGo” y “CCh”, respectivamente. Estos valores de rendimiento en grano se hallan incrementados con respec- to a aquellos que se obtienen en las zonas andinas y muy próximas a los que se informan para otras condiciones ambientales, como por ejemplo en EuropaQuinoa crops surface is increasing in Argentinean Northwest (NOA) and especially in Valles Calchaquíes (high valley located in the Argentinean Northwest). The most utilized variety is CICA, originated from the other peruvian one called Amarilla de Marangani. There is not antecedent about this preference in Argentinean Northwest. In order to contribute to quinoa agronomical management the effect of sowing density on the morphology and specially grain yields were studied. Experience was per formed in a locality in the Valles Calchaquíes (Amaicha del Valle, Tucumán, Argentina) located at 1,995 m asl. One of the utilized methods for planting was the realization of the same by hand (“CICA separated, CGo”) and the other one using a planting machine (“CICA together, CCh”). With both method we get a sowing density of 4.2 and 27.9 plants/m. Plant height, stem diameter, specific leaf area (SLA), phosporus and nitrogen leaf content and grain yields (kg/ha) were increased in “CICA separated, CGo”. Grain diameter clases showed a high proportion (65%) of grain with a diameter ≥ 1,41 mm in both treatments. But in “CICA separated, CGo” we registered and increase in the proportion of the grain with a diameter ≥ 1.68 mm. The last data is very important because market prefers a large grain. In general, grain yield were 5,389 kg/ha and 3,049 kg/ha for “CICA separated, CGo” and “CICA together, CCh” respectively. The last values are greater in relation to those obtained in andean high mountains and very close to those obtained in others environment conditions like in Europe.EEA FamailláFil: Erazzu, Luis Ernesto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía; ArgentinaFil: González, Juan A. Fundación Miguel Lillo. Instituto de Ecología; ArgentinaFil: Buedo, Sebastián E. Fundación Miguel Lillo. Instituto de Ecología; ArgentinaFil: Prado, Fernando E. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales. Cátedra de Fisiología Vegetal; Argentin

Análise dos padrões de publicação científica sobre ética na ciência

This study aims to carry out a bibliometric analysis of articles on research ethics in the Web of Science and Scopus databases. Therefore, from the data collected in the databases, 4614 publications considered suitable for analysis were selected. Bibliometric indicators on the annual evolution of the publications, the most used keywords in the publications, the countries that publish the most on the subject, the sources of publication, among others, were elaborated. According to the analysis of the journals in which the most articles related to the subject of study are published, it is evident that only one of them explicitly includes them within its area of focus, the rest of the publications are especially in the areas of engineering. , pure sciences and health. On the other hand, among the countries with the greatest production in research ethics, Argentina, Brazil, Chile, China, Colombia, Mexico, Norway, Peru stand out, evidencing an interest on the part of Latin American countries, particularly in the last 5 years. which coincides with the dissemination and creation of public policies for scientific integrity. The findings obtained in the research provide the scientific community with a general framework on the state of the art of publications on the subject.Este estudio tiene como objetivo realizar un análisis bibliométrico de artículos sobre ética en investigación, en la base de datos de Scopus, en el periodo de 2000 al 2022. Por lo tanto, de los datos recopilados en las bases de datos, se seleccionaron 4614 publicaciones consideradas aptas para el análisis. Se determinaron algunos patrones en el comportamiento de las publicaciones sobre ética en la investigación como: palabras clave más utilizadas en las publicaciones, países que más publican sobre el tema y fuentes de publicación. Según el análisis de las revistas en las que más se publican artículos relacionados con el tema de ética en la investigación, tan solo una de las revistas lo incluye como un tema de su alcance y enfoque; el resto de las publicaciones son de las áreas de ingeniería, ciencias puras y salud, y no tratan el tema de la ética directamente. Por otra parte, dentro de los países con mayor producción de artículos sobre ética de la investigación se destacan Argentina, Brasil, Chile, China, Colombia, México, Noruega y Perú; esto evidencia un interés por parte de los países latinoamericanos en este tema, particularmente en los últimos cinco años, que coincide con la divulgación y creación de políticas públicas para la integridad científica. Los hallazgos obtenidos en la investigación proporcionan a la comunidad científica un marco general sobre los patrones y comportamiento de las publicaciones científicas sobre el tema.Este estudo tem como objetivo realizar uma análise bibliométrica de artigos sobre ética em pesquisa nas bases de dados Web of Science e Scopus. Assim, a partir dos dados coletados nas bases de dados, foram selecionadas 4.614 publicações consideradas adequadas para análise. Foram elaborados indicadores bibliométricos sobre a evolução anual das publicações, as palavras-chave mais utilizadas nas publicações, os países que mais publicam sobre o assunto, as fontes de publicação, entre outros. De acordo com a análise dos periódicos em que mais artigos relacionados ao tema de estudo são publicados, fica evidente que apenas um deles os inclui explicitamente dentro de sua área de foco, o restante das publicações são especialmente nas áreas de engenharia. , ciências puras e saúde. Por outro lado, entre os países com maior produção em ética em pesquisa, destacam-se Argentina, Brasil, Chile, China, Colômbia, México, Noruega, Peru, evidenciando interesse por parte dos países latino-americanos, particularmente nos últimos 5 anos, o que coincide com a divulgação e criação de políticas públicas de integridade científica. Os achados obtidos na pesquisa fornecem à comunidade científica um quadro geral sobre o estado da arte das publicações sobre o tema