Applying wrapper-based variable selection techniques to predict MFIs profitability: evidence from Peru

In this paper, we analyse the main factors explaining the profitability (ROA) of Microfinance Institutions (MFIs) in Peru from 2011 to 2107. We apply three wrapper techniques to asample of 168 Peruvians MFIs and 69 attributes obtained from MIX Market database. After running the algorithms M5', knearest neighbours (KNN) and Random Forest, we find that the M5' algorithm provides the best fit for predicting ROA. Particularly, the key variable of the regression tree is the percentage of expenses over assets and, depending on its value, it is followed by net income after taxes and before donations, or profit margins.En este trabajo, analizamos los principales factores que explican la rentabilidad (ROA) de las Instituciones de Microfinanzas (IMF) en Perú desde 2011 hasta 2107. Aplicamos tres técnicas de envoltura a una muestra de 168 IMF peruanas y 69 atributos obtenidos de la base de datos MIX Market. Después de ejecutar los algoritmos M5', vecinos knearest (KNN) y Random Forest, encontramos que el algoritmo M5' proporciona el mejor ajuste para predecir el ROA. En particular, la variable clave del árbol de regresión es el porcentaje de gastos sobre activos y, dependiendo de su valor, le sigue la utilidad neta después de impuestos y antes de donaciones o márgenes de utilidad

Inside the metropolis: the articulation of Spanish metropolitan areas into local labor markets

In this article, we delimit local labor markets (LLMs) in order to analyze the internal structure and organization of Spanish metropolitan areas. LLMs are defined as self-contained and cohesive areas in terms of commuting flows. Unlike the conventional approach to polycentrism based on the analysis of commuting flows that begins with the identification of subcenters, our analytical strategy does assume any a priori structure and is compatible with the relationship between places of work and residence having other locational and spatial organization patterns. The analysis is performed at three different scales of detail linked to three self-containment levels for the LLMs delimited and three population groups (total, males, and females). The results show that metropolitan areas are complex, fuzzy, multidimensional spaces, where the conditions of spatial organization are manifested in different ways depending on the parameters and variables used.This work was supported by the Spanish Ministry of Economy and Competitiveness [grant numbers CSO2011-29943-C03-01, CSO2011-29943-C03-02, CSO2014-55780-C3-1-P, and CSO2014-55780-C3-2-P (National R&D&I Plan)]

Facial disability index (FDI): adaptation to Spanish, reliability and validity

Objectives: To adapt to Spanish the facial disability index (FDI) described by VanSwearingen and Brach in 1995 and to assess its reliability and validity in patients with facial nerve paresis after parotidectomy. Study Design: The present study was conducted in two different stages: a) cross-cultural adaptation of the questionnaire and b) cross-sectional study of a control group of 79 Spanish-speaking patients who suffered facial paresis after superficial parotidectomy with facial nerve preservation. The cross-cultural adaptation process comprised the following stages: (I) initial translation, (II) synthesis of the translated document, (III) retro-translation, (IV) review by a board of experts, (V) pilot study of the pre-final draft and (VI) analysis of the pilot study and final draft. Results: The reliability and internal consistency of every one of the rating scales included in the FDI (Cronbach's alpha coefficient) was 0.83 for the complete scale and 0.77 and 0.82 for the physical and the social well-being subscales. The analysis of the factorial validity of the main components of the adapted FDI yielded similar results to the original questionnaire. Bivariate correlations between FDI and House-Brackmann scale were positive. The variance percentage was calculated for all FDI components. Conclusions: The FDI questionnaire is a specific instrument for assessing facial neuromuscular dysfunction which becomes a useful tool in order to determine quality of life in patients with facial nerve paralysis. Spanish adapted FDI is equivalent to the original questionnaire and shows similar reliability and validity. The proven reproducibi- lity, reliability and validity of this questionnaire make it a useful additional tool for evaluating the impact of facial nerve paralysis in Spanish-speaking patients

The delimitation of metropolitan areas as a governance instrument: the case of the Valencian Community

Partiendo de la naturaleza multidimensional, flexible y abierta de los procesos urbanos, el trabajo propone una metodología de definición y delimitación de áreas metropolitanas con fines normativos, asumiendo que existen tantas potenciales delimitaciones como perspectivas desde las que es posible abordar esta tarea. El enfoque propuesto se articula en varios pasos que toman en consideración aspectos normativos, vínculos funcionales, características morfológicas, delimitaciones preexistentes, la gobernanza multinivel y las redes de cooperación. En el trabajo se ilustra esta aproximación aplicándola en la Comunidad Valenciana, cuyos espacios metropolitanos forman un caso de estudio idóneo al tratarse de ejemplos paradigmáticos de tipos distintos de configuración metropolitana. Los análisis realizados, extrapolables a otros territorios, muestran que en el enfoque propuesto el producto final no es tanto un mapa de las áreas metropolitanas valencianas como la sistematización de los distintos aspectos que deben considerarse en el proceso de definición. Así, son igualmente relevantes las fases del proceso, la discusión en ellas recogida, y no únicamente las fronteras que delimitan las áreas metropolitanas. Ello facilita que estas sean modulables, adaptables a la coyuntura específica en que son adoptadas, a través de la consideración crítica de las decisiones tomadas en cada una de las etapas.Based on the multidimensional, flexible and open nature of urban processes, the paper proposes a methodology for defining and delimiting metropolitan areas for normative purposes, assuming that there are as many potential delimitations as different perspectives from which it is possible to approach this task to suit public policy objectives. The proposed approach is articulated in several steps that take into consideration normative aspects, functional links, morphological characteristics, pre-existing delimitations, multilevel governance and intermunicipal cooperation networks. The paper illustrates this approach by applying it to the Valencian Community, whose metropolitan areas form an ideal case study as they are paradigmatic examples of different types of metropolitan configuration. The analyses carried out, which can be extrapolated to other territories, show that in the proposed approach the final product is not so much a map of the Valencian metropolitan areas as the systematization of the different aspects to be considered in the definition process and in making it available to the agents involved. Thus, the deliverable are the phases of the process, the discussion therein collected, and not only the boundaries that delimit the metropolitan areas. This facilitates that these are modulable, adaptable to the specific circumstances in which they are adopted, through the critical consideration of the decisions taken in each of the stages.Proyectos PID2020/112734RB-C31 y PID2020-114896RB-I00 (Agencia Estatal de Investigación, AEI/10.13039/501100011033; Plan Estatal de Investigación Científica y Técnica y de Innovación 2017-2020) y AICO/2021/062 (Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital; Programa de I+D+I de la Comunitat Valenciana)

Nitrogen-carbon graphite-like semiconductor synthesized from uric acid

A new carbon-nitrogen organic semiconductor has been synthesized by pyrolysis of uric acid. This layered carbon-nitrogen material contains imidazole-, pyridine (naphthyridine)- and graphitic-like nitrogen, as evinced by infrared and X-ray photoelectron spectroscopies. Quantum chemistry calculations support that it would consist of a 2D polymeric material held together by hydrogen bonds. Layers are stacked with an interplanar distance between 3.30 and 3.36 Å, as in graphite and coke. Terahertz spectroscopy shows a behavior similar to that of amorphous carbons, such as coke, with non-interacting layers. This material features substantial differences from polymeric carbon nitride, with some characteristics closer to those of nitrogen-doped graphene, in spite of its higher nitrogen content. The direct optical band gap, dependent on the polycondensation temperature, ranges from 2.10 to 2.32 eV. Although in general the degree of crystallinity is low, in the material synthesized at 600 °C some spots with a certain degree of crystallinity can be found

Effectiveness and Safety of the Switch from Remicade® to CT-P13 in Patients with Inflammatory Bowel Disease

[Background and Aims] To evaluate the clinical outcomes in patients with IBD after switching from Remicade® to CT-P13 in comparison with patients who maintain Remicade®.[Methods] Patients under Remicade® who were in clinical remission with standard dosage at study entry were included. The ‘switch cohort’ [SC] comprised patients who made the switch from Remicade® to CT-P13, and the ‘non-switch’ cohort [NC] patients remained under Remicade®.[Results] A total of 476 patients were included: 199 [42%] in the SC and 277 [58%] in the NC. The median follow-up was 18 months in the SC and 23 months in the NC [p < 0.01]. Twenty-four out of 277 patients relapsed in the NC; the incidence of relapse was 5% per patient-year. The cumulative incidence of relapse was 2% at 6 months and 10% at 24 months in this group. Thirty-eight out of 199 patients relapsed in the SC; the incidence rate of relapse was 14% per patient-year. The cumulative incidence of relapse was 5% at 6 months and 28% at 24 months. In the multivariate analysis, the switch to CT-P13 was associated with a higher risk of relapse (HR = 3.5, 95% confidence interval [CI] = 2–6). Thirteen percent of patients had adverse events in the NC, compared with 6% in the SC [p < 0.05].[Conclusions] Switching from Remicade® to CT-P13 might be associated with a higher risk of clinical relapse, although this fact was not supported in our study by an increase in objective markers of inflammation. The nocebo effect might have influenced this result. Switching from Remicade® to CT-P13 was safe.This research has been funded by grants from the Instituto de Salud Carlos III [PI13/00041 and FI17/00143]

Single-cultivar extra virgin olive oil classification using a potentiometric electronic tongue

Label authentication of monovarietal extra virgin olive oils is of great importance. A novel approach based on a potentiometric electronic tongue is proposed to classify oils obtained from single olive cultivars (Portuguese cvs. Cobrançosa, Madural, Verdeal Transmontana; Spanish cvs. Arbequina, Hojiblanca, Picual). A meta-heuristic simulated annealing algorithm was applied to select the most informative sets of sensors to establish predictive linear discriminant models. Olive oils were correctly classified according to olive cultivar (sensitivities greater than 97%) and each Spanish olive oil was satisfactorily discriminated from the Portuguese ones with the exception of cv. Arbequina (sensitivities from 61% to 98%). Also, the discriminant ability was related to the polar compounds contents of olive oils and so, indirectly, with organoleptic properties like bitterness, astringency or pungency. Therefore the proposed E-tongue can be foreseen as a useful auxiliary tool for trained sensory panels for the classification of monovarietal extra virgin olive oils.This work was co-financed by FCT and FEDER under Program COMPETE (Project PEst-C/EQB/LA0020/2013)

Una aproximación difusa a la delimitación y configuración del sistema metropolitano español a través de la movilidad residencia-trabajo

Comunicación presentada en el X Coloquio y Jornadas de Campo de Geografía Urbana, Asturias, Cantabria y País Vasco, 28 junio-3 julio 2010.Este trabajo se ha realizado en el marco de los proyectos SEJ2007-67767-C04-01 y SEJ2007-67767-C04-02, financiados por el Ministerio de Ciencia e Innovación y FEDER dentro del Plan Nacional de I+D+i

Social and territorial transformation due to the increasing of labour mobility in Andalusia

Entre 1991 y 2001, tal como se deduce de la información de los censos de población de ambos años, se ha producido un importante incremento de la movilidad en Andalucía por razón de trabajo, especialmente de los desplazamientos entre municipios cercanos. Este trabajo indaga sobre los factores relacionados como causas, y también como consecuencias, con tal incremento. En primer lugar, los cambios en la estructura sectorial, ocupacional y socioeconómica de la población ocupada. En segundo lugar, la ampliación espacial de los mercados locales de trabajo. Y, en tercer lugar, la evolución de la organización espacial de la movilidad, especialmente de la movilidad metropolitana. La conclusión es que la mayoría de los factores considerados han contribuido al aumento de la movilidad. Sin embargo, las transformaciones de la organización y estructura del sistema urbano, aunque son consecuencia parcial de cambios en la estructura ocupacional y en los mercados locales de trabajo, son también su causa principal.According to 1991 and 2001 Census data, commuting has experienced an important growth in Andalusia, especially among neighbour municipalities. This paper explores the factors linked with that growth, both as causes and as consequences: changes in the composition of the working population in terms of sector of activity and socioeconomic groups, the spatial widening of local labour markets and the evolution of commuting spatial organization, particularly in metropolitan areas. Findings show that a majority of factors taken into account have a significant contribution to the expansion and intensification of commuting flows. Among these factors developments in the organization and structure of the urban system are identified as the main reasons for such commuting growth. However, these developments are also, to a certain degree, a result of changes in economic activities and socioeconomic structure, and in the associated local labour markets

Transformaciones sociales y territoriales en el incremento de la movilidad por razón de trabajo en Andalucía

According to 1991 and 2001 Census data, commuting has experienced an important growth in Andalusia, especially among neighbour municipalities. This paper explores the factors linked with that growth, both as causes and as consequences: changes in the composition of the working population in terms of sector of activity and socioeconomic groups, the spatial widening of local labour markets and the evolution of commuting spatial organization, particularly in metropolitan areas. Findings show that a majority of factors taken into account have a significant contribution to the expansion and intensification of commuting flows. Among these factors developments in the organization and structure of the urban system are identified as the main reasons for such commuting growth. However, these developments are also, to a certain degree, a result of changes in economic activities and socioeconomic structure, and in the associated local labour markets.Entre 1991 y 2001, tal como se deduce de la información de los censos de población de ambos años, se ha producido un importante incremento de la movilidad en Andalucía por razón de trabajo, especialmente de los desplazamientos entre municipios cercanos. Este trabajo indaga sobre los factores relacionados como causas, y también como consecuencias, con tal incremento. En primer lugar, los cambios en la estructura sectorial, ocupacional y socioeconómica de la población ocupada. En segundo lugar, la ampliación espacial de los mercados locales de trabajo. Y, en tercer lugar, la evolución de la organización espacial de la movilidad, especialmente de la movilidad metropolitana. La conclusión es que la mayoría de los factores considerados han contribuido al aumento de la movilidad. Sin embargo, las transformaciones de la organización y estructura del sistema urbano, aunque son consecuencia parcial de cambios en la estructura ocupacional y en los mercados locales de trabajo, son también su causa principal