La regulación del mercado alimentario : el caso de la Guadalajara bajomedieval

El estudio de los mercados medievales es el camino hacia la comprensión de los modernos. La política local y su impacto en el comercio de alimentos son los pilares de un mundo de regulación en el que el espíritu comercial estaba ya despertando. Guadalajara en la Baja Edad Media muestra perfectamente cómo los ayuntamientos fijaban sus disposiciones para controlar cada actividad y evitar situaciones de crisis.The study of medieval markets is the way to the understanding of the modern ones. The local policy and its impact on the food trade are the pillars of a world of regulation where the commercial spirit was already waking up. Guadalajara, in the Late Middle Ages, is a perfect example of how town councils fixed their decrees in order to control each activity and to avoid crisis situations

Are fit indices really fit to estimate the number of factors with categorical variables?: some cautionary findings via Monte Carlo Simulation

This paper is not the copy of record and may not exactly replicate the authoritative document published in the APA journal. Please do not copy or cite without author's permission. The final article is available, upon publication, at: http://dx.doi.org/10.1037/met0000064An early step in the process of construct validation consists of establishing the fit of an unrestricted "exploratory" factorial model for a prespecified number of common factors. For this initial unrestricted model, researchers have often recommended and used fit indices to estimate the number of factors to retain. Despite the logical appeal of this approach, little is known about the actual accuracy of fit indices in the estimation of data dimensionality. The present study aimed to reduce this gap by systematically evaluating the performance of 4 commonly used fit indices-the comparative fit index (CFI), the Tucker-Lewis index (TLI), the root mean square error of approximation (RMSEA), and the standardized root mean square residual (SRMR)-in the estimation of the number of factors with categorical variables, and comparing it with what is arguably the current golden rule, Horn's (1965) parallel analysis. The results indicate that the CFI and TLI provide nearly identical estimations and are the most accurate fit indices, followed at a step below by the RMSEA, and then by the SRMR, which gives notably poor dimensionality estimates. Difficulties in establishing optimal cutoff values for the fit indices and the general superiority of parallel analysis, however, suggest that applied researchers are better served by complementing their theoretical considerations regarding dimensionality with the estimates provided by the latter metho

An Unexpected Access to a New Sphingoid Base Containing a Vinyl Sulfide Unit

An unexpected access to a new sphingoid base containing a vinyl sulfide unit is described. The process involves the ‘one-pot' regioselective opening of an epoxide with a thiolate, followed by intramolecular acyl transfer, base-promoted elimination, and final hydrolysis. Excess sodium hydride and high dilution conditions are required for optimal yields. The process is amenable to a variety of thiolates. The resulting compounds can be regarded as new hybrid sphingoid bases that combine some structural motifs present in other reported sphingolipid analogues.Peer reviewe

Trajectoires industrielles et gouvernance local dans des villes intermédiaires de la périphérie madrilène : les cas de Getafe et Alcalá de Henares

In recent years the interest for the role of intermediate cities in territorial development has become a central issue in urban development studies. More specifically, the construction of metropolitan areas based on polycentric urban structures raises the role these cities play in the construction of metropolitan outskirts and their ability to overcome the challenges posed by the particular conditions of these environments. In this paper, we present the cases of Getafe and Alcalá de Henares, both characterized by outstanding developmental trajectories in the Madrid metropolitan context for its success in building a model of development characterized by the importance of the industrial sector. It is argued that this has been possible thanks to the enterprises’ innovative capacity, and the characteristics of their respective institutional contexts. The research was based on 68 interviews conducted in both cities as well as quantitative sources commonly used in studies of industrial activity and urban development.En años recientes el interés por el papel de las ciudades intermedias en el desarrollo territorial ha devenido un tema central en los estudios sobre desarrollo urbano. Más concretamente, la construcción de regiones metropolitanas a partir de estructuras urbanas policéntricas plantea el papel que estas ciudades juegan en la construcción de las periferias metropolitanas, así como su capacidad para sortearlos desafíos impuestos por las particulares condiciones de esos entornos. En el presente trabajo, se presentan los casos de Getafe y Alcalá de Henares cuyas trayectorias de desarrollo destacan en el contexto metropolitano madrileño por haber logrado construir un modelo de desarrollo caracterizado por la importancia del sector industrial. Se argumenta que ello ha sido posible gracias a la capacidad innovadora empresarial, así como a las características de los respectivos contextos institucionales. La investigación se apoya en 68 entrevistas realizadas en ambas ciudades así como en las fuentes cuantitativas habitualmente utilizadas en los estudios de la actividad industrial y el desarrollo urbano.Durant des années récentes l’intérêt pour le rôle des villes intermédiaires dans le développement territorial est devenu un sujet central dans les études sur le développement urbain. Plus concrètement, la construction de régions métropolitaines à partir de structures urbaines polycéntriques pose le rôle que ces villes jouent dans la construction des périphéries métropolitaines, ainsi que leur capacité pour éviter les défis imposés par les conditions particulières de ces environnements. Dans le présent travail, on présente les cas de Getafe et Alcalá de Henares dont les trajectoires de développement soulignent dans le contexte métropolitain madrilène pour avoir obtenu construire un modèle de développement caractérisé par l’importance du secteur industriel. On fait valoir que cela a été possible grâce à la capacité innovatrice patronale, ainsi qu’aux caractéristiques des contextes institutionnels respectifs. La recherche s’appuie sur 68 interviews réalisées dans les deux villes, ainsi que dans les sources quantitatives habituellement utilisées dans les études de l’activité industrielle et le développement urbain

Exploratory bi-factor analysis with multiple general factors

Exploratory bi-factor analysis (EBFA) is a very popular approach to estimate models wherespecific factors are concomitant to a single, general dimension. However, the models typic-ally encountered in fields like personality, intelligence, and psychopathology involve morethan one general factor. To address this circumstance, we developed an algorithm (GSLiD)based on partially specified targets to perform exploratory bi-factor analysis with multiplegeneral factors (EBFA-MGF). In EBFA-MGF, researchers do not need to conduct independentbi-factor analyses anymore because several bi-factor models are estimated simultaneously inan exploratory manner, guarding against biased estimates and model misspecification errorsdue to unexpected cross-loadings and factor correlations. The results from an exhaustiveMonte Carlo simulation manipulating nine variables of interest suggested that GSLiD outper-forms the Schmid-Leiman approximation and is robust to challenging conditions involvingcross-loadings and pure items of the general factors. Thereby, we supply an R package(bifactor) to make EBFA-MGF readily available for substantive research. Finally, we useGSLiD to assess the hierarchical structure of a reduced version of the Personality Inventoryfor DSM-5 Short Form (PID-5-SF)This research was supported by Grant PSI2017-85022-P (Ministerio de Ciencia, Innovación y Universidades, Spain) and the UAM IIC Chair Psychometric Models and Application

Syndromes leading to failure: an exploratory research.

Prediction of corporate failure research typically focused on the design of multivariate prediction models for the discrimination betw een failed and non-failed firms. This research atracted some criticism due to the inability to formulate generally applicable models. Several reasons may have led to the im possibility of formulating such models: it has been argued that firms suffering financial distress may have incentives to manipulate accounting information in order to increase users’ confidence; statisti cal techniques could overadjust prediction models; and finally, the existence of different failure processes is not considered by prior research. The main objective of the present research is to investigate the unique characteristics of failed companies, the reasons for each particular failure and the presence of different failure processes. The present study aims to be the first step in the opening of a new stage in the development of a theoretical framework on corporate failure. It is assumed that there exist different paths to failure, instead of a simple differentiation between healthy and failed firms. This is the main contribution of the paper, which is relevant to both researchers and practitioners. It opens up new possibilities for future research, following new experimental designs. For practitioners, it constitutes a new framework for the development of decisi on-aid tools (raising the opportunity to use decision making systems based on different rules or models for different paths)

Procesos de fracaso empresarial en PYMES. Identificación y contrastación empírica.

La investigación sobre fracaso empresarial tiene como objetivo el diseño de modelos predictivos. Hasta ahora, la investigación existente utiliza un mismo planteamiento: la separación de las empresas en dos categorías, sanas y fracasadas. Aunque estos modelos llegan a proporcionar tasas iniciales de éxito aceptables, su uso posterior muestra una cierta inestabilidad predictiva y escasa fiabilidad en contextos diferentes a los iniciales. Este trabajo investiga la existencia de diferentes procesos de fracaso , primer paso para el desarrollo de un nuevo marco teórico para futuros diseños experimentales, que superen el modelo simplista de dicotomía sanas / fracasadas

Modeling general, specific, and method variance in personality measures: Results for ZKA-PQ and NEO-PI-R

Reprinted by permission of SAGE PublicationsContemporary models of personality assume a hierarchical structure in which broader traits contain narrower traits. Individual differences in response styles also constitute a source of score variance. In this study, the bifactor model is applied to separate these sources of variance for personality subscores. The procedure is illustrated using data for two personality inventories—NEO Personality Inventory–Revised and Zuckerman–Kuhlman–Aluja Personality Questionnaire. The inclusion of the acquiescence method factor generally improved the fit to acceptable levels for the Zuckerman–Kuhlman–Aluja Personality Questionnaire, but not for the NEO Personality Inventory–Revised. This effect was higher in subscales where the number of direct and reverse items is not balanced. Loadings on the specific factors were usually smaller than the loadings on the general factor. In some cases, part of the variance was due to domains being different from the main one. This information is of particular interest to researchers as they can identify which subscale scores have more potential to increase predictive validit

The use of IRT to investigate the relationships between the g factor and cognitive tasks

Las relaciones entre el factor g y tareas de procesamiento de la información han abierto la puerta a la comprensión de la naturaleza de g ( Jensen, 1998). No obstante, es necesario superar determinados problemas metodológicos para poder comprender hasta qué punto las diferencias en g son ocasionadas por diferencias en procesos cognitivos. En este sentido, la falta de fiabilidad de las puntuaciones en las tareas de procesos puede llevar a conclusiones equivocadas sobre la naturaleza de dichas relaciones. Un medio de abordar este problema es seleccionar a las personas con un menor error de estimación del nivel de habilidad. Los resultados muestran un aumento de las correlaciones entre g y memoria de trabajo en el grupo de sujetos mejor medidos frente al grupo de personas con un error de estimación mayorMany authors have looked for the relations between the g factor and cognitive tasks in order to find out the nurture of the g factor (Jensen, 1998). Nevertheless, some methodological problems must be solved to understand if the individual differences in g are differences in cognitive processes. One of them is the low reliability of the scores in this kind of tasks. On the grounds of the standard error of the ability level estimation, we hypothesized that the correlations between the g factor and a working memory task would be larger in the g roup of the subjects better measured (less standard error). The results support this hypothesi