The probability of default in internal ratings based (IRB) models in Basel II: an application of the rough sets methodology

El nuevo Acuerdo de Capital de junio de 2004 (Basilea II) da cabida e incentiva la implantación de modelos propios para la medición de los riesgos financieros en las entidades de crédito. En el trabajo que presentamos nos centramos en los modelos internos para la valoración del riesgo de crédito (IRB) y concretamente en la aproximación a uno de sus componentes: la probabilidad de impago (PD). Los métodos tradicionales usados para la modelización del riesgo de crédito, como son el análisis discriminante y los modelos logit y probit, parten de una serie de restricciones estadísticas. La metodología rough sets se presenta como una alternativa a los métodos estadísticos clásicos, salvando las limitaciones de estos. En nuestro trabajo aplicamos la metodología rought sets a una base de datos, compuesta por 106 empresas, solicitantes de créditos, con el objeto de obtener aquellos ratios que mejor discriminan entre empresas sanas y fallidas, así como una serie de reglas de decisión que ayudarán a detectar las operaciones potencialmente fallidas, como primer paso en la modelización de la probabilidad de impago. Por último, enfrentamos los resultados obtenidos con los alcanzados con el análisis discriminante clásico, para concluir que la metodología de los rough sets presenta mejores resultados de clasificación, en nuestro caso.The new Capital Accord of June 2004 (Basel II) opens the way for and encourages credit entities to implement their own models for measuring financial risks. In the paper presented, we focus on the use of internal rating based (IRB) models for the assessment of credit risk and specifically on the approach to one of their components: probability of default (PD). In our study we apply the rough sets methodology to a database composed of 106 companies, applicants for credit, with the object of obtaining those ratios that discriminate best between healthy and bankrupt companies, together with a series of decision rules that will help to detect the operations potentially in default, as a first step in modelling the probability of default. Lastly, we compare the results obtained against those obtained using classic discriminant análisis. We conclude that the rough sets methodology presents better risk classification results.Junta de Andalucía P06-SEJ-0153

Migration, nostalgia and the building of a food imaginary: Mexican migrants at "La Pulga" market in San Joaquin Valley, California

In the context of transnational migration, ethnic markets function as segmented spaces where migrants as a group may be observed on many levels. Provisioning in the market (as much by immigrants as by natives or long-term residents) as well as the consumption of prepared food in situ compel a multiplicity of social interactions that facilitate knowledge and social relations, including recipes, memories, nostalgia, circulation of products and culinary techniques. In addition, a market can acquire a role as a meaningful transnational space of confluence for a system of relations and representations that help to decipher the complex social reality of subjects involved in a transnational migration phenomenon. With this paper we aim to highlight how a migratory context as well as the collectivization of a sensory experience as seen in an itinerant Mexican food market in California lead to the construction of a food imaginary related to Mexican food when it is disassociated from the original context in which it is produced. Thus, by means of an ethnographic approach, this paper aims to demonstrate how the collectivization of a sensory experience, framed under culinary nostalgia and triggered by the performativity and reflexivity of the subjects that take part in market activity, enables the construction of a food imaginary for the Mexican migrants that are regular clients of an itinerant market in California. (author's abstract

Internal models (IRB) in Basel II: an approach to determining the probability of default

The New Accord of Basel, known as Basel II, opens the way for and encourages the implementation of credit entities' own models for measuring their financial risks. In this paper, we focus on the internal models for the assessment of credit risk (IRB), and specifically on the approach to one of their components: the probability of default (PD). Our paper is structured in three sections. In the first section, we present the most significant aspects of the credit risk treatment in Basel II. In the second part, the available financial literature is reviewed. And finally, we undertake an empirical application with the object of determining what is or are the variables that are able to explain why a company defaults. Furthermore, this would serve as a preventive "warning system" for financial entities

EXPERIMENTS SIMULATION AND DESIGN TO SET TRAFFIC LIGHTS’ OPERATION RULES

[EN] In this paper it is used the experimental design to minimize the travel time of motor vehicles, in one of the most important avenues of Celaya City in Guanajuato, Mexico, by means of optimal synchronization of existing traffic lights. In the optimization process three factors are considered: the traffic lights’ cycle times, the synchrony defined as stepped, parallel and actual, and speed limit, each one with 3 evaluation levels. The response variables to consider are: motor vehicles’ travel time, fuel consumption and greenhouse effect gas (CO2) emissions. The different experiments are performed using the simulation model developed in the PTV-VISSIM software, which represents the vehicle traffic system. The obtained results for the different proposed scenarios allow to find proper levels at which the vehicle traffic system must be operated in order to improve mobility, to reduce contamination rates and decrease the fuel consumption for the different motor vehicles that use the avenue.Espinoza Mondragón, J.; Jimenez García, J.; Medina Flores, JM.; Vázquez López, JA.; Téllez Vázquez, S. (2016). EXPERIMENTS SIMULATION AND DESIGN TO SET TRAFFIC LIGHTS’ OPERATION RULES. En XII Congreso de ingeniería del transporte. 7, 8 y 9 de Junio, Valencia (España). Editorial Universitat Politècnica de València. 907-919. https://doi.org/10.4995/CIT2016.2015.4093OCS90791

A multilevel model of job inclusion of employees with disabilities: The role of organizational socialization tactics, coworkers social support, and an inclusive team context

The main objective of this study was to examine the role of social context as a main mechanism to understand how organizational socialization tactics influence job inclusion of employees with disabilities (EWD). Specifically, we analyzed the influence of socialization that employees without disability received by the organization on two indicators of EWD's job inclusion, organizational learning, and desire to stay in the organization. First, we examined the mediator role of social support perceived by EWD in the aforementioned relationships. Second, we used a cross-level moderating approach to examine how an inclusive team context (affective climate toward disability and stigma shared by team members without disability) impacts on the relationship between EWD's perceptions of social support and both indicators of job inclusion. Our sample was composed by 258 employees included in 66 teams from 15 organizations. Each team included one worker with disability. Two sources of information were used: EWD to measure perceived social support and indicators of job inclusion, and coworkers to measure socialization tactics, team affective climate toward disability, and team stigma. We used multilevel modeling and cross-level moderation with MPLUS to test our hypotheses. Our results showed that EWD's perceptions of social support mediated the relationship between organizational socialization tactics and both indicators of EWD's job inclusion. Team affective climate toward disability and team stigma moderated the relationship between EWD's perceptions of social support and organizational learning. Thus, the social context showed potential improving EWD's job inclusion. Theoretical and practical implications are discussed.Ministerio de Educación, Cultura y Deporte FPU15/01560Ministerio de Economía, Industria y Competitividad PID2019-110093GB-I0

Characterization of size-sorted particulated matter collected on solid substrates by laser-ionization mass spectrometry and laser-induced breakdown spectrometry

Resumen de trabajos realizados mediante excitación láser de material particulado y su posterior análisis mediante espectroscopía óptica de emisión o ionización.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Linear and non-linear relationships between job demands-resources and psychological and physical symptoms of service sector employees. When is the midpoint a good choice?

Related to the research of working conditions, the link between organizational factors and health was traditionally analyzed using linear models. However, the literature analysis suggests inconsistencies in linear models predicting workers’ health levels. To clarify this issue, this exploratory research compares the linear and non-linear relationships between job demands-resources (task complexity, time pressure, contact with users, and job autonomy), and the psychological and physical symptoms of employees working in the main five service subsectors: commerce, horeca (hotels, restaurants, and cafés), public administration, education, and healthcare. With a final sample of 4,047 participants, our study data were extracted from the II Andalusian Working Conditions Survey. Following the theoretical framework of JD-R Model and considering the Vitamin Model theoretical approach for non-linear relationships, our results showed that there were significant differences among the five subsectors analyzed regarding the linear and non-linear relationships between job demands-resources and psychological and physical symptoms of employees. Furthermore, task complexity generated non-linear relationships in higher proportion than time pressure and contact with users. Likewise, non-linear relationships found showed a U-shape. Moreover, the findings of non-linear relationships suggested that medium levels of task complexity should not be exceeded to avoid further negative impact on psychological and physical symptoms for service sector employees, preserving their health. Finally, some general practical implications of work environment interventions are suggested.Ministerio de Universidades PID2019-110093GB-I0

Los modelos internos (IRB) en Basilea II: la metodología rough set en una aproximación a la determinación de la probabilidad de impago

Basilea II da cabida e incentiva la implantación de modelos propios para la medición de los riesgos financieros en las entidades de crédito. En el trabajo que presentamos nos centramos en los modelos internos para la valoración del riesgo de crédito (IRB) y concretamente en la aproximación a uno de sus componentes: la probabilidad de impago (PD). Nuestro trabajo se estructura en tres bloques, en el primero mostramos los aspectos más sobresalientes del tratamiento del riesgo de crédito en Basilea II, para centrarnos en las necesidades de desarrollar modelos matemáticos que nos permitan valorar el riesgo de crédito tal cual exige Basilea. En el segundo exponemos teóricamente el modelo matemático objeto de nuestro trabajo: rough set. A continuación realizamos una aplicación empírica de dicha metodología a una base de datos de una entidad financiera andaluza, con el objetivo de aproximarnos al cálculo de una de las variables en la valoración del riesgo de crédito, la probabilidad de impag

La frontera gastronómica de Cholula, Puebla: entre la gentrificación y la turistificación

In this paper we show some tensions displayed at the foodscapes of Cholula (Mexico). Based on a qualitative approach through semi structured interviews, participant observation and media content analysis, we aim to show that the existence of a culinary border enables two different foodscapes framed by several interests. Thus, we state that the culinary border stimulates two opposite phenomena that shows the contrast in the assembly of the local foodscapes. One the one hand, the aim of conservation of the foodscape due to a tourism intention that appeals narratives and discourses about heritage and traditionality; on the other hand, the boost of a culinary cosmopolitanism that incentivizes food gentrification processes that shown the particularities of the food modernity.En este trabajo mostramos las tensiones que se generan en el paisaje alimentario de la demarcación de Cholula (México). En ésta existen dos municipios entre los que se genera una frontera culinaria. A partir de una aproximación cualitativa por medio de entrevistas semiestructuradas, observación participante y análisis de contenido en medios digitales, queremos demostrar que la existencia de la frontera gastronómica parece habilitar dos paisajes culinarios diferenciados que obedecen a distintos intereses. De esta manera, podríamos afirmar que la frontera gastronómica habilita y dinamiza fenómenos opuestos que favorecen el contraste en el ensamblaje gastronómico. Por un lado, la intención de la estatización del paisaje que obedece a lógica de la turistificación que apela a la recuperación de la tradicionalidad y la historia para favorecer los discursos en torno al turismo y al patrimonio. Por otro, el cosmopolitismo culinario que incentiva procesos de gentrificación alimentaria que evidencian los particularismos propios de la modernidad alimentaria

Prolonged food deprivation increases mRNA expression of deiodinase 1 and 2, and thyroid hormone receptor β-1 in a fasting-adapted mammal

Food deprivation in mammals is typically associated with reduced thyroid hormone (TH) concentrations and deiodinase content and activity to suppress metabolism. However, in prolonged-fasted, metabolically active elephant seal pups, TH levels are maintained, if not elevated. The functional relevance of this apparent paradox is unknown and demonstrates variability in the regulation of TH levels, metabolism and function in food-deprived mammals. To address our hypothesis that cellular TH-mediated activity is upregulated with fasting duration, we quantified the mRNA expression and protein content of adipose and muscle deiodinase type I (DI1) and type II (DI2), and TH receptor beta-1 (THrβ-1) after 1, 3 and 7 weeks of fasting in northern elephant seal pups (N=5–7 per week). Fasting did not decrease the concentrations of plasma thyroid stimulating hormone, total triiodothyronine (tT(3)), free T(3), total thyroxine (tT(4)) or free T(4), suggesting that the hypothalamic–pituitary–thyroid axis is not suppressed, but rather maintained during fasting. Mean mRNA expression of adipose DI1 and DI2 increased threefold and fourfold, respectively, and 20- and 30-fold, respectively, in muscle. With the exception of adipose DI1, protein expression of adipose DI2 and muscle DI1 and DI2 increased twofold to fourfold. Fasting also increased adipose (fivefold) and muscle (fourfold) THrβ-1 mRNA expression, suggesting that the mechanisms mediating cellular TH activity are upregulated with prolonged fasting. The data demonstrate a unique, atypical mechanism of TH activity and regulation in mammals adapted to prolonged food deprivation in which the potential responsiveness of peripheral tissues and cellular TH activity are increased, which may contribute to their lipid-based metabolism