Policy Analysis Tool Applied to Colombian Needs: PATACON Model Description

In this document we lay out the microeconomic foundations of a dynamic stochastic general equilibrium model designed to forecast and to advice monetary policy authorities in Colombia. The model is called Policy Analysis Tool Applied to Colombian Needs (PATACON). In companion documents we present other aspects of the model and its platform, including the estimation of the parameters that affect the dynamics and the impulse responses functions.Monetary Policy, DSGE, Small open economy. Classification JEL: E32, E52, F41.

Método numérico para la calibración de un modelo dsge

En este artículo se propone un método numérico para la calibración de un modelo de equilibrio general dinámico y estocástico (dsge). Esencialmente, este consiste en utilizar un algoritmo híbrido de optimización, primero para encontrar un estado estacionario del modelo y luego para minimizar una función objetivo que se define según el propósito que tenga el investigador con el proceso de calibración. El algoritmo propuesto consiste en una aplicación del algoritmo de simulated annealing, seguida de métodos tradicionales de optimización. Las bondades del algoritmo se analizan mediante simulaciones de Monte Carlo, usando un modelo de economía cerrada cuyo estado estacionario no tiene solución analítica. Los resultados de este ejercicio muestran que el algoritmo propuesto genera resultados más precisos y que utiliza menos recursos computacionales que las alternativas tradicionales. Además, se presentan los resultados de la calibración de un modelo para la economía colombiana que consta de 179 ecuaciones y que se ajusta a cincuenta razones con cincuenta parámetros. La máxima desviación porcentual entre las razones del modelo y los valores correspondientes de la economía colombiana es de 7,9% y, en veintinueve de los cincuenta casos, esta desviación es menor o igual a 1%.simulated annealing, calibración, dsge, estado estacionario.

A semi-analytical perspective on massive galaxies at z∼0.55z\sim0.55

The most massive and luminous galaxies in the Universe serve as powerful probes to study the formation of structure, the assembly of mass, and cosmology. However, their detailed formation and evolution is still barely understood. Here we extract a sample of massive mock galaxies from the semi-analytical model of galaxy formation (SAM) GALACTICUS from the MultiDark-Galaxies, by replicating the CMASS photometric selection from the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). The comparison of the GALACTICUS CMASS-mock with BOSS-CMASS data allows us to explore different aspects of the massive galaxy population at $0.5<z<0.6$, including the galaxy-halo connection and the galaxy clustering. We find good agreement between our modelled galaxies and observations regarding the galaxy-halo connection, but our CMASS-mock over-estimates the clustering amplitude of the 2-point correlation function, due to a smaller number density compared to BOSS, a lack of blue objects, and a small intrinsic scatter in stellar mass at fixed halo mass of $<0.1$ dex. To alleviate this problem, we construct an alternative mock catalogue mimicking the CMASS colour-magnitude distribution by randomly down-sampling the SAM catalogue. This CMASS-mock reproduces the clustering of CMASS galaxies within 1$\sigma$ and shows some environmental dependency of star formation properties that could be connected to the quenching of star formation and the assembly bias.Comment: 15 pages, 10 figures, 2 tables, submitted to MNRA

Real-Time optimization using the Modifier Adaptation methodology

[ES] La gestión óptima de las plantas de proceso normalmente se lleva a cabo en una capa de optimización en tiempo real (Real Time Optimization, RTO) que actúa sobre la capa de control y que toma decisiones considerando objetivos económicos en base a un  modelo del proceso, normalmente estacionario. Sin embargo, dicha operación óptima no está garantizada debido a la presencia de incertidumbre entre el modelo usado para la toma de decisiones y el proceso real. Con la idea de conducir el proceso a su punto de operación óptimo usando un modelo que se sabe incierto o erróneo, surge la metodología de adaptación de modificadores (Modifier Adaptation o MA). En dicha metodología, el problema de optimización económica de la capa RTO es modificado mediante unos términos correctores, conocidos como modificadores, estimados a partir de medidas de la planta, con el objetivo de conducir el proceso a su punto de operación óptimo. El presente artículo hace una revisión de las técnicas desarrolladas hasta el momento dentro de la metodología MA analizando sus características y modos de implementación.[EN] Optimal process operation is carried out by a Real-Time Optimization (RTO) layer which operates above the control layer and takes decisions based on steady-state plant models by considering economic objectives. However, this optimal operation is not guaranteed due to the presence of plant-model mismatch. To bring the process to the optimum operating point, the economic optimization problem solved in the RTO layer is changed following the Modifier Adaptation methodology (MA). This methodology changes the economic optimization problem solved in the RTO layer by adding some corrector terms or modifiers estimated from plant measurements to bring the process to the real optimum. This article presents a review of the different MA techniques developed until now and analyzing their features and the way to implement them.Este trabajo ha sido realizado gracias al proyecto DPI2015-70975-P del MINECO del Gobierno de España bajo la beca FPI BES-2013-062737.Rodríguez-Blanco, T.; Sarabia, D.; De Prada, C. (2018). Optimización en Tiempo Real utilizando la Metodología de Adaptación de Modificadores. Revista Iberoamericana de Automática e Informática industrial. 15(2):133-144. https://doi.org/10.4995/riai.2017.8846OJS13314415

The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Angular clustering tomography and its cosmological implications

We investigate the cosmological implications of studying galaxy clustering using a tomographic approach applied to the final BOSS DR12 galaxy sample, including both auto- and cross-correlation functions between redshift shells. We model the signal of the full shape of the angular correlation function, $\omega(\theta)$, in redshift bins using state-of-the-art modelling of non-linearities, bias and redshift-space distortions. We present results on the redshift evolution of the linear bias of BOSS galaxies, which cannot be obtained with traditional methods for galaxy-clustering analysis. We also obtain constraints on cosmological parameters, combining this tomographic analysis with measurements of the cosmic microwave background (CMB) and type Ia supernova (SNIa). We explore a number of cosmological models, including the standard $\Lambda$CDM model and its most interesting extensions, such as deviations from w_\rm{DE} = -1, non-minimal neutrino masses, spatial curvature and deviations from general relativity using the growth-index $\gamma$ parametrisation. These results are, in general, comparable to the most precise present-day constraints on cosmological parameters, and show very good agreement with the standard model. In particular, combining CMB, $\omega(\theta)$ and SNIa, we find a value of w_\rm{DE} consistent with $-1$ to a precision better than 5\% when it is assumed to be constant in time, and better than 6\% when we also allow for a spatially-curved Universe.Comment: 21 pages, 18 figures, accepted for publication MNRAS. The data used in this analysis is publicly available at https://sdss3.org/science/boss_publications.ph

Occurrence of organotin compounds in waters of the spanish coast under the European Water Framework Directive

Organotin compounds (OTCs), such as tributyltin (TBT), are persistent organic pollutants that are present in water samples (surface water, river water, sea water, waste water, etc.) because of anthropogenic activities (antifouling agents in ship paints, biocides in polymers, etc.). The toxicity and endocrine disruption potential of these chemicals have been demonstrated even at very low levels (<1 ng L−1) (Devos et al. 2012). Due to the extensive presence of OTCs in all environmental media as well as their adverse effects on human health and biota, quantitative and qualitative determination of those com-pounds in complex environmental matrices has become a matter of great concern, mainly butyl and phenyl-substituted. Also, these compounds are included in the list of priority substances according to the EU Directive 2013/39/EU amending Directives 2000/60/EC and 2008/105/EC as regards priority substances in the field of water policy. This directive specifies annual average environmental quality standard (AA-EQS) of 0.2 ng L−1 TBT and a maximum allowable environmental quality standard (MAC-EQS) of 1.5 ng L−1 TBT for all surface waters. Samples were collected in two semiconfined coastal areas, one of them an area with high industrial and port activities (Ría de Vigo) and the other one with high touristic and agricultural activity (Mar Menor).The sampling campaigns were performed in spring and autumn of 2015. The levels of MBT, DBT, TBT, MPhT, DPhT and TPhT in the seawater samples were analyzed by HS-SPME-GC–QqQMS/ MS method (Moscoso-Pérez et al. 2015). MPhT, DPhT and TPhT were not detected in any sample at levels higher than LOQ. For butylated compounds, MBT, DBT and TBT were detected in 100% of the analyzed samples in the Mar Menor. In the Vigo estuary, MBT has been detected in 83.3% of the samples, the DBT in 75% and the TBT in 88%. The TBT is present in 92% of the total of 39 analyzed samples, being detected in 100% of the samples of the Mar Menor and in 88% of the samples of the Ría de Vigo. These levels are similar than those detected in other locations, and lower than the detected in ports near the coast of Gijón characterized by a great maritime traffic (Centineo et al. 2004).Program of Consolidation and Structuring of Units of Competitive Investigation of the University System of Galicia (Xunta de Galicia) potentially cofinanced by ERDF in the frame of the operative Program of Galicia 2007-2013 (reference: GRC2013-047) and by the Ministry of Economy and Competitiveness (IMPACTA, project reference: CTM2013-48194-C3-2-R, and ARPA-ACUA, project reference: CTM2016-77945-C3-3-R)

A targeted likelihood estimation comparing cefepime and piperacillin/tazobactam in critically ill patients with community-acquired pneumonia (CAP)

Cefepime and piperacillin/tazobactam are antimicrobials recommended by IDSA/ATS guidelines for the empirical management of patients admitted to the intensive care unit (ICU) with community-acquired pneumonia (CAP). Concerns have been raised about which should be used in clinical practice. This study aims to compare the effect of cefepime and piperacillin/tazobactam in critically ill CAP patients through a targeted maximum likelihood estimation (TMLE). A total of 2026 ICU-admitted patients with CAP were included. Among them, (47%) presented respiratory failure, and (27%) developed septic shock. A total of (68%) received cefepime and (32%) piperacillin/tazobactam-based treatment. After running the TMLE, we found that cefepime and piperacillin/tazobactam-based treatments have comparable 28-day, hospital, and ICU mortality. Additionally, age, PTT, serum potassium and temperature were associated with preferring cefepime over piperacillin/tazobactam (OR 1.14 95% CI [1.01–1.27], p = 0.03), (OR 1.14 95% CI [1.03–1.26], p = 0.009), (OR 1.1 95% CI [1.01–1.22], p = 0.039) and (OR 1.13 95% CI [1.03–1.24], p = 0.014)]. Our study found a similar mortality rate among ICU-admitted CAP patients treated with cefepime and piperacillin/tazobactam. Clinicians may consider factors such as availability and safety profiles when making treatment decisions

Dietary Fat Patterns and Outcomes in Acute Pancreatitis in Spain

Background/Objective: Evidence from basic and clinical studies suggests that unsaturated fatty acids (UFAs) might be relevant mediators of the development of complications in acute pancreatitis (AP). Objective: The aim of this study was to analyze outcomes in patients with AP from regions in Spain with different patterns of dietary fat intake. Materials and Methods: A retrospective analysis was performed with data from 1,655 patients with AP from a Spanish prospective cohort study and regional nutritional data from a Spanish cross-sectional study. Nutritional data considered in the study concern the total lipid consumption, detailing total saturated fatty acids, UFAs and monounsaturated fatty acids (MUFAs) consumption derived from regional data and not from the patient prospective cohort. Two multivariable analysis models were used: (1) a model with the Charlson comorbidity index, sex, alcoholic etiology, and recurrent AP; (2) a model that included these variables plus obesity. Results: In multivariable analysis, patients from regions with high UFA intake had a significantly increased frequency of local complications, persistent organ failure (POF), mortality, and moderate-to-severe disease in the model without obesity and a higher frequency of POF in the model with obesity. Patients from regions with high MUFA intake had significantly more local complications and moderate-to-severe disease; this significance remained for moderate-to-severe disease when obesity was added to the model. Conclusions: Differences in dietary fat patterns could be associated with different outcomes in AP, and dietary fat patterns may be a pre-morbid factor that determines the severity of AP. UFAs, and particulary MUFAs, may influence the pathogenesis of the severity of AP

SDSS-III Baryon Oscillation Spectroscopic Survey data release 12 : galaxy target selection and large-scale structure catalogues

The Baryon Oscillation Spectroscopic Survey (BOSS), part of the Sloan Digital Sky Survey (SDSS) III project, has provided the largest survey of galaxy redshifts available to date, in terms of both the number of galaxy redshifts measured by a single survey, and the effective cosmological volume covered. Key to analysing the clustering of these data to provide cosmological measurements is understanding the detailed properties of this sample. Potential issues include variations in the target catalogue caused by changes either in the targeting algorithm or properties of the data used, the pattern of spectroscopic observations, the spatial distribution of targets for which redshifts were not obtained, and variations in the target sky density due to observational systematics. We document here the target selection algorithms used to create the galaxy samples that comprise BOSS. We also present the algorithms used to create large-scale structure catalogues for the final Data Release (DR12) samples and the associated random catalogues that quantify the survey mask. The algorithms are an evolution of those used by the BOSS team to construct catalogues from earlier data, and have been designed to accurately quantify the galaxy sample. The code used, designated mksample, is released with this paper.Publisher PDFPeer reviewe