Performance in post-compulsory education: evidence from vocational and academic tracks

This paper investigates the factors in_uencing grade performance in two different high school tracks (academic and vocational), including the effect of the amount of work achieved while studying. The empirical strategy analyzes grade progression through the outcomes, passing, repeating and dropping out, conditioning on previous outcomes, and dealing with the endogeneity introduced by the working variable. The analysis is based on a unique Spanish data with information on schooling and labor histories. Findings show that working reduces performance in both tracks, mainly during the first year, although the ffects are less detri- mental in the vocational path. Additionally, good performance in compulsory education, at- tending a private high school, or having high-educated parents improve outcomes, particularly in academic high school.

The post-communist fertility puzzle

Fertility has unanimously declined across the entire post-communist region. This study explores the variation in fertility trends over time among these countries and assesses to what degree three explanations are applicable: second demographic transition (SDT), postponement transition (PPT) or reaction to the economic crisis. Moreover, on the basis of SDT and PPT theoretical tenets, as well as descriptive evidence, the economic context is hypothesized to be linked to two processes of fertility decline conversely. The results show that no one theoretical explanation is sufficient to explain the complex fertility declines across the entire post-communist region from 1990 to 2003. In some countries, a great part of the decline in fertility occurred before significant postponement of childbearing began, which indicates that the dramatic decline was due to stopping behavior or postponement of higher order births. Postponement of first births, either through PPT or SDT processes, greatly contributed to fertility decline in a small number of countries. Pooled cross-sectional time-series analyses of age-specific birthrates confirm that these two distinct processes are present and show that the economic crisis explanation has explanatory power for declining birth rates. In contrast, logistic regressions show that the likelihood of postponing childbirth increases with improved economic conditions. These results confirm the importance of taking the economic context into account when discussing explanations for fertility decline. More specifically, the results indicate that the severity and duration of economic crisis, or absence thereof, influenced the extent and manner in which fertility declined.

Rendimiento diagnóstico de la spect-tc post terapéutica en la estadificación inicial del cáncer diferenciado de tiroides

El rastreo corporal total (RCT) luego de la primera radioablación con 131I en pacientes diagnosticados de carcinoma diferenciado de tiroides (CDT) permite una re-estadificación de la enfermedad. Sin embargo, su información anatómica es escasa y la elevada actividad de los restos tiroideos puede interferir con la detección de adenopatías cervicales. En este estudio se determinó el valor diagnóstico de la SPECT-TC respecto al RCT, concluyendo que la misma aporta información relevante para determinar el compromiso ganglionar, resolviendo los patrones indeterminados observados en los estudios planares y permitiendo una mejor estadificación de los pacientes al final de su periodo de tratamiento.

Completing contracts ex post: How car manufacturers manage car dealers

This article illustrates how contracts are completed ex post in practice and, in so doing, indirectly suggests what the real function of contracts may be. Our evidence comes from the contracts between automobile manufacturers and their dealers in 23 dealership networks in Spain. Franchising dominates automobile distribution because of the need to decentralize pricing and control of service decisions. It motivates local managers to undertake these activities at minimum cost for the manufacturer. However, it creates incentive conflicts, both between manufacturers and dealers and among dealers themselves, concerning the level of sales and service provided. It also holds potential for expropriation of specific investments. Contracts deal with these conflicts by restricting dealers decision rights and granting manufacturers extensive completion, monitoring and enforcement powers. The main mechanism that may prevent abuse of these powers is the manufacturers reputational capital.

When to carry eccentric products? Optimal retail assortment under consumer returns

To understand whether retailers should consider consumer returns when merchandising, we study howthe optimal assortment of a price-taking retailer is influenced by its return policy. The retailer selects itsassortment from an exogenous set of horizontally differentiated products. Consumers make purchase andkeep/return decisions in nested multinomial logit fashion. Our main finding is that the optimal assortmenthas a counterintuitive structure for relatively strict return policies: It is optimal to offer a mix of the mostpopular and most eccentric products when the refund amount is sufficiently low, which can be viewed asa form of risk sharing between the retailer and consumers. In contrast, if the refund is sufficiently high, orwhen returns are disallowed, optimal assortment is composed of only the most popular products (a commonfinding in the literature). We provide preliminary empirical evidence for one of the key drivers of our results:more eccentric products have higher probability of return conditional on purchase. In light of our analyticalfindings and managerial insights, we conclude that retailers should take their return policies into accountwhen merchandising.

Revenue management under general discrete choice model of consumer behavior

Customer choice behavior, such as 'buy-up' and 'buy-down', is an importantphe-nomenon in a wide range of industries. Yet there are few models ormethodologies available to exploit this phenomenon within yield managementsystems. We make some progress on filling this void. Specifically, wedevelop a model of yield management in which the buyers' behavior ismodeled explicitly using a multi-nomial logit model of demand. Thecontrol problem is to decide which subset of fare classes to offer ateach point in time. The set of open fare classes then affects the purchaseprobabilities for each class. We formulate a dynamic program todetermine the optimal control policy and show that it reduces to a dynamicnested allocation policy. Thus, the optimal choice-based policy caneasily be implemented in reservation systems that use nested allocationcontrols. We also develop an estimation procedure for our model based onthe expectation-maximization (EM) method that jointly estimates arrivalrates and choice model parameters when no-purchase outcomes areunobservable. Numerical results show that this combined optimization-estimation approach may significantly improve revenue performancerelative to traditional leg-based models that do not account for choicebehavior.

Ex post bargaining, labor coordination and wage formation at the firm level

We lay out a model of wage bargaining with two leading features:bargaining is ex post to relevant investments and there isindividual bargaining in firms without a Union. We compareindividual ex post bargaining to coordinated ex post bargainingand we analyze the effects on wage formation. As opposed to exante bargaining models, the costs of destroying the employmentrelationship play a crucial role in determining wages. Highfiring costs in particular yield a rent for employees. Ourtheory points to a employer size-wage effect that is independentof the production function and market power. We derive a simpleleast squares specification from the theoretical model thatallow us to estimate components of the wage premium fromcoordination. We reject the hypothesis that labor coordinationdoes not alter the extensive form of the bargaining game. Laborcoordination substantially increases bargaining power butdecreases labor's ability to pose costly threats to the firm.

Salience and consumer choice

We present a theory of context-dependent choice in which a consumer's attention is drawnto salient attributes of goods, such as quality or price. An attribute is salient for a good when itstands out among the good's attributes, relative to that attribute's average level in the choice set (orgenerally, the evoked set). Consumers attach disproportionately high weight to salient attributesand their choices are tilted toward goods with higher quality/price ratios. The model accounts fora variety of disparate evidence, including decoy effects, context-dependent willingness to pay, andlarge shifts in demand in response to price shocks.

Consumer choice in competitive location models: Formulations and heuristics

A new direction of research in Competitive Location theory incorporatestheories of Consumer Choice Behavior in its models. Following thisdirection, this paper studies the importance of consumer behavior withrespect to distance or transportation costs in the optimality oflocations obtained by traditional Competitive Location models. To dothis, it considers different ways of defining a key parameter in thebasic Maximum Capture model (MAXCAP). This parameter will reflectvarious ways of taking into account distance based on several ConsumerChoice Behavior theories. The optimal locations and the deviation indemand captured when the optimal locations of the other models are usedinstead of the true ones, are computed for each model. A metaheuristicbased on GRASP and Tabu search procedure is presented to solve all themodels. Computational experience and an application to 55-node networkare also presented.

Post crisis challenges to bank regulation

The current crisis has swept aside not only the whole of the US investment banking industry butalso the consensual perception of banking risks, contagion and their implication for bankingregulation. As everyone agrees now, risks where mispriced, they accumulated in neuralgic pointsof the financial system, and where amplified by procyclical regulation as well as by the instabilityand fragility of financial institutions.The use of ratings as carved in stone and lack of adequate procedure to swiftly deal withsystemic institutions bankruptcy (whether too-big-to-fail, too complex to fail or too-many to fail).The current paper will not deal with the description and analysis of the crisis, already covered inother contributions to this issue will address the critical choice regulatory authorities will face. Inthe future regulation has to change, but it is not clear that it will change in the right direction. Thismay occur if regulatory authorities, possibly influenced by public opinion and political pressure,adopt an incorrect view of financial crisis prevention and management. Indeed, there are twoapproaches to post-crisis regulation. One is the rare event approach, whereby financial crises willoccur infrequently, but are inescapable.

Mutant Huntingtin impairs post-Golgi trafficking to lysosomes by delocalizing optineurin/Rab8 complex from the Golgi apparatus

Huntingtin regulates post-Golgi trafficking of secreted proteins. Here, we studied the mechanism by which mutant huntingtin impairs this process. Colocalization studies and Western blot analysis of isolated Golgi membranes showed a reduction of huntingtin in the Golgi apparatus of cells expressing mutant huntingtin. These findings correlated with a decrease in the levels of optineurin and Rab8 in the Golgi apparatus that can be reverted by overexpression of full-length wild-type huntingtin. In addition, immunoprecipitation studies showed reduced interaction between mutant huntingtin and optineurin/Rab8. Cells expressing mutant huntingtin produced both an accumulation of clathrin adaptor complex 1 at the Golgi and an increase of clathrin-coated vesicles in the vicinity of Golgi cisternae as revealed by electron microscopy. Furthermore, inverse fluorescence recovery after photobleaching analysis for lysosomal-associated membrane protein-1 and mannose-6-phosphate receptor showed that the optineurin/Rab8-dependent post-Golgi trafficking to lysosomes was impaired in cells expressing mutant huntingtin or reducing huntingtin levels by small interfering RNA. Accordingly, these cells showed a lower content of cathepsin D in lysosomes, which led to an overall reduction of lysosomal activity. Together, our results indicate that mutant huntingtin perturbs post-Golgi trafficking to lysosomal compartments by delocalizing the optineurin/Rab8 complex, which, in turn, affects the lysosomal function.

Late and post-Hercyniam low temperature veins in the Catalonian Coastal Ranges

Many of the veins enclosed within the Paleozoic basement of the Catalonian Coastal Ranges show severa1 common characteristics: low temperature of formation (between 75 and 200C), the presence of complex polisaline fluids and a certain relationship to the pretriassic paleosurface. Mineralogical composition and age are variable, ranging from Pb-Zn veins with carbonate gangue of late Hercynian age through metal poor fluorite rich veins to barite rich veins of Triasssic age. Mineralizing fluids are not related to late Hercynianmagmatism and deposition took place in active fractures developed either in extensional as in compressive regimes.

La Obra de Cayetano Garviso: 1807- post. 1871: cirujano vasco-navarro liberal en América

L'autor d'aquest llibre dona a conèixer alguns aspectes de l'exercici de la medicina en la dècada de 1840 a la zona del Río de la Plata, a partir de la figura del metge basc-navarrés Cayetano Garviso, cirurgià que emigrà a Argentina durant la Primera Guerra Carlista. Ara bé, tot i que aquest personatge es va moure per bona part de Sudamèrica, el treball es centra en la part de la seva biografia i el seu exercici professional desenvolupada a Espanya, Montevideo i Buenos Aires.

Analcime crystallization and compositional profiles - Comparing approaches to detect post-depositional alterations in archaeological pottery

The approaches of comparative studies and profile measurements, often used in order to detect post-depositional alterations of ceramics, have been applied simultaneously to two sets of Roman pottery, both of which include altered individuals. As analytical techniques, Neutron Activation Analysis and X-Ray Diffraction have been used. Both approaches lead to substantially different results. This shows that they detect different levels of alteration and should complement each other rather than being used exclusively. For the special process of a glassy phase decomposition followed by a crystallization of the Na-zeolite analcime, the results suggest that it changes high-fired calcareous pottery rapidly, and so fundamentally that the results of various archaeometric techniques can be severely disturbed.