Does mid-season change of coach improve team performance? Evidence from the history of the NBA

This research has advanced in the understanding of the effect of hiring new coaches on performance of NBA teams, when change is achieved in the middle of the season. Changing a coach is an important managerial decision which does not guarantee improvement of results in the short term, i.e. in the same season. Using an easily understandable procedure based on comparison of proportions in a finite population approach framework, we show that only about 15% of new coaches outperformed in a significantly way their predecessors. In order to maximize the probability of success, highly experienced coaches, with a long career as former NBA players should be signed. In addition, change should be made before season advances. These three factors slightly contribute to increase the probability of success, being the most important variable the winning percentage of the team at the moment of change. Therefore, worse teams are more probable to be successful than better teams when a change is made. Finally, implications and limitations are discussed

A second chance to win

[SPA] Esta investigación analiza en el entorno de una competición deportiva el impulso en la motivación que para los equipos tiene el obtener una segunda oportunidad de alcanzar el objetivo deseado. Para ello, utilizamos la liga profesional de baloncesto estadounidense (NBA), donde dos equipos compiten por la victoria en cada partido. A través del análisis de 390 contiendas que acabaron en empate en su tiempo reglamentario, y por ende dirimieron el resultado final en la prórroga, mostramos que el equipo que consigue empatar el partido en la última jugada del mismo tiene mayor probabilidad de ganar en la prórroga si actúa como visitante pero no si actúa como local. Anotar primero en la prórroga, asimismo, es un factor que incrementa la probabilidad de victoria tanto para el equipo local como para el visitante. [ENG] This research analyzes the boost in motivation that teams experience when getting a second chance to achieve the desired objective within competition settings. To achieve this aim we analyzed the NBA framework, where two teams compete for victory in each game. Through the analysis of 390 matches that ended in a draw, and therefore the final result was reached in the overtime, we show how teams tying a game on the final play of the match are more likely to win in the overtime when playing away, but not at home. Being the first team to score in the overtime increases the probability of winning the game for both home and away situations.Los autores agradecen la financiación recibida del proyecto ECO2015-65637-P (MINECO/FEDER). Asimismo, este trabajo es el resultado de la actividad desarrollada en el marco del Programa de Ayudas a Grupos de Excelencia de la Región de Murcia, de la Fundación Séneca, Agencia de Ciencia y Tecnología de la Región de Murcia proyecto 19884/GERM/15

La medición de la satisfacción del consumidor de servicios deportivos a través de la lógica borrosa

This study focuses on measuring customer satisfaction within the context of sports services by using a novel approach in sport psychology: modelling uncertainty through the application of fuzzy logic. several analytical procedures for dealing with fuzziness have been described in order to verify empirically the extent to which this methodology complements the traditional statistical approach. this study examines the relationships between numerical evaluations of customer satisfaction and the degree of uncertainty linked to these verbal judgements. the proposed approach enriches the information on the attitudes of sport service consumers and overcomes the shortcomings of the "third-person" perspective. In addition, this proposal is robust against two sources of bias: scale coarseness, and interaction between numerical and verbal judgements

Datos meteorológicos a través de los radares MODE-S

Presentación realizada en el Foro de Usuarios Aeronáuticos, celebrado el 18 de noviembre de 2015 en los Servicios Centrales de AEMET en Madri

Nowcasting solar radiation using cloud satellite and high resolution numerical model outputs

Póster presentado en: EMS Annual Meeting: European Conference for Applied Meteorology and Climatology celebrado del 4–8 de septiembre de 2017 en Dublin, IrelandAEMET (the Spanish Meteorological Agency) is currently developing a project for the Spanish transmission system operator, Red Eléctrica de España, to improve hourly Global Horizontal Irradiance (GHI) and direct Normal Irradiance (DNI) forecasts in Spanish solar power plants. Nowcasting is a technique for very short-range forecasting (normally within 6h ahead) covering only a very specific geographic region. There is a need of using nowcasting models to forecast the availability of solar radiation in order to low electricity generating costs. We present the current status of a nowcasting tool developed by AEMET that provides every 15 min the hourly solar radiation accumulated fluxes for the coming 4 hours. The meteorological data used for this model are: satellite cloud type observations and forecasts based on high resolution winds (EUMETSAT SAFNWC/MSG software package outputs), radiation from high resolution numerical weather prediction model (HARMONIE/AROME radiation outputs) or a combination of both sources of information depending on different forecast time horizons. The accuracy of the tool has been analyzed comparing the GHI and DNI forecasts with the ground solar radiation measurements from seven stations of AEMET network. The verification results in terms of RMSE are similar to those found in the bibliography, with the advantage that the satellite component of the tool does not require the use of a model to convert satellite imagery to average insolation on the groun

Spider diversity (Arachnida: Araneae) in two different coffee management systems and surrounding tropical forest during two contrasting seasons in Oaxaca, Mexico

This study focuses on species richness, abundance, diversity, and seasonal variation of spiders in two coffee plantations with different crop management and a portion of tropical forest in two municipalities of La Costa region of Oaxaca, Mexico, using manual collection, foliage beating and pitfall traps. We collected 2,210 spiders belonging to 35 families, 100 genera and 146 species. The inventory includes 51 new species records for Oaxaca. Completeness values for two estimators indicate that the level of representation of inventories range from 68.25% to 78.44%, and the proportion of singletons range from 33.72% to 38.14%. Spider abundance in the rainy season was significantly lower than during the dry season. Spider abundance in the Tropical Forest was significantly lower than Monoculture site with the foliage beating method. Polyculture was the site with the lowest spider abundance with the pitfall traps. Rarefaction curves did not show significant differences in species richness between the sites and seasons. Hutcheson t-test showed that spider diversity was significantly lower in Monoculture than Tropical Forest during the rainy season. This study contributes to the knowledge of the arachnofauna of Mexico and particularly of the state of Oaxaca.Este estudio se enfoca en la riqueza de especies, abundancia, diversidad y variación estacional de las arañas en dos cultivos de café con diferente manejo y una porción de bosque tropical en dos municipios de la región Costa de Oaxaca, México, utilizando la colecta manual, agitación del follaje y trampas de caída. Se recolectaron 2,210 arañas pertenecientes a 35 familias, 100 géneros y 146 especies. El inventario incluye 51 nuevos registros de especies para Oaxaca. Los valores de completitud de dos estimadores indican que el nivel de representación de los inventarios oscila entre el 68.25 % y el 78.44 %, mientras que la proporción de singletons fue de 33.72 % y 38.14 %. La abundancia de arañas en la estación lluviosa fue significativamente menor que durante la estación secas. La abundancia de arañas en el Bosque Tropical fue significativamente menor que en el Monocultivo con el método de agitación de follaje. El Policultivo fue el sitio con menor abundancia de arañas con el método de trampas de caída. Las curvas de rarefacción no mostraron diferencias significativas en la riqueza de especies entre los sitios y estaciones. La prueba t de Hutcheson mostró que la diversidad de arañas fue significativamente menor en el Monocultivo que en el Bosque Tropical durante la estación lluviosa. Este estudio contribuye al conocimiento de la aracnofauna de México y particularmente del estado de Oaxaca