Diagnosing and Mitigating Market Power in Chile's Electricity Industry

This paper examines generators' incentives to exercise market power and the strategies they would follow if all electricity supplies were traded in an hourly-unregulated spot market. The industry is modelled as a Cournot duopoly with a competitive fringe; particular care is given to the hydro scheduling decision. Quantitative simulations of generators� strategic behaviour indicate that the largest (Endesa) would have the incentive and power to act unilaterally. It would schedule its hydro resources to take advantage of differences in price electricity: too little supply in high demand periods and too much in low demand periods. Two market power mitigation measures are analysed: requiring Endesa to divest some of its generating capacity, and fixed price forward contracts for dominant generators. Conditions for the development of a voluntary contract market are analysed, as it is not practical to rel

Fixed Effect Estimation of Large T Panel Data Models

This article reviews recent advances in fixed effect estimation of panel data models for long panels, where the number of time periods is relatively large. We focus on semiparametric models with unobserved individual and time effects, where the distribution of the outcome variable conditional on covariates and unobserved effects is specified parametrically, while the distribution of the unobserved effects is left unrestricted. Compared to existing reviews on long panels (Arellano and Hahn 2007; a section in Arellano and Bonhomme 2011) we discuss models with both individual and time effects, split-panel Jackknife bias corrections, unbalanced panels, distribution and quantile effects, and other extensions. Understanding and correcting the incidental parameter bias caused by the estimation of many fixed effects is our main focus, and the unifying theme is that the order of this bias is given by the simple formula p/n for all models discussed, with p the number of estimated parameters and n the total sample size.Comment: 40 pages, 1 tabl

RESEARCH IN ECONOMICS IN SPAIN: RANKINGS OF INSTITUTIONS AND AUTHORS

In this paper we analyse the research in Economics in Spain during the 1990s considering the contributions of both Spanish and foreign economist who have worked in Spain during that period. To do so, we use different bibliometric indicators in order to elaborate rankings for both institutions and researchers. These rankings can be useful for several potentials users such as: a) Evaluation Agencies and Funding Bodies to help them in grant-allocation decisions; b) Graduate students who whish to choose the right institution to complete their postgraduate education, and c) Young Ph Ds who have entered the academic job market and need information about the research perfomance of different institutions.

Publishing performance in economics: Spanish rankings (1990-1999)

This paper contributes to the growing literature that analyses the Spanish publishing performance in Economics throughout the 1990s. Several bibliometric indicators are used in order to provide Spanish rankings (of both institutions and individual authors) based on Econlit journals. Further, lists of the ten most influential authors and articles over that period, in terms of citations, are reported.Publicad

GMM estimation of a production function with panel data : an application to Spanish manufacturing firms

In this paper we consider the estimation of a Cobb-Douglas production function using a panel dataset of Spanish manufacturing firms. As it is stressed in the econometric literature, the use of standard GMM first differences estimators to eliminate the unobserved firm-specific effects may yield imprecise estimates, particularly in the case of the estimation of the production function. The reason is that the high persistence of output and inputs involved in the estimation of production functions make that their lagged levels to be weak instruments for the first differences of these series. The extended GMM estimator proposed by Arellano and Bover (1995) considers further orthogonality conditions based on lagged differences as instruments for the equation in levels. This approach has been applied to the estimation of technological parameters by Blundell and Bond (1999). Our estimation results, based on this approach, confirm the better performance of the extended GMM estimator compared to the standard first-differenced GMM estimato

Identifying asymmetric, multi-period Euler equations estimated by non-linear IV/GMM

In this article, the identification of instrumental variables and generalized method of moment (GMM) estimators with multi-period perceptions is discussed. The state space representation delivers a conventional first order condition that is solved for expectations when the Generalized Bézout Theorem holds. Here, it is shown that although weak instruments may be enough to identify the parameters of a linearized version of the Quasi-Reduced Form (Q-RF), their existence is not sufficient for the identification of the structural model. Necessary and sufficient conditions for local identification of the Quasi-Structural Form (Q-SF) derive from the product of the data moments and the Jacobian. Satisfaction of the moment condition alone is only necessary for local and global identification of the Q-SF parameters. While the conditions necessary and sufficient for local identification of the Q-SF parameters are only necessary to identify the expectational model that satisfies the regular solution. If the conditions required for the decomposition associated with the Generalized Bézout Theorem are not satisfied, then limited information estimates of the Q-SF are not consistent with the full solution. The Structural Form (SF) is not identified in the fundamental sense that the Q-SF parameters are not based on a forward looking expectational model. This suggests that expectations are derived from a forward looking model or survey data used to replace estimated expectations

Model of a continuous crystallization process for a sorbet by the moments methodology

La etapa de precongelación es un importante paso en el proceso de manufactura de helados y sorbetes dado que las condiciones de operación tienen una fuerte influencia sobre la microestructura y por consecuencia sobre los atributos sensoriales del producto final. Esta etapa de precongelación es llevada a cabo en un intercambiador de calor de superficie raspada donde la calidad del producto es fuertemente influenciada por las condiciones de operación tales como la temperatura de evaporación de un refrigerante, el gasto másico de la alimentación, la velocidad del raspador y una presión provocada por la introducción de aire. Con la finalidad de estudiar la pertinencia de un sistema de control basado en la influencia de las variables del proceso sobre la calidad del producto, este trabajo presenta un modelo para una cristalización continua de un sorbete utilizando la metodología de momentos, el cual es validado con datos experimentales. El modelo realizado por esta metodología de momentos es capaz de representar la influencia de las condiciones de operación durante la cristalización de sorbete sobre las características finales del producto tales como el tamaño de cristal y la temperatura de salida del intercambiador de superficie raspada (ICSR) en ausencia de aire. El modelo basado en momentos se estudia, entonces, como la reducción del modelo de la ecuación de balance de población e incluye los fenómenos de nucleación heterogénea y crecimiento. De este modo, el modelo desarrollado representa requerimientos computacionales mínimos y está altamente adaptado para tareas de optimización y/o control del proceso.Freezing is an important step in the manufacturing process of ice-cream and sorbet, since the operating conditions have a strong influence on the micro-structure, and consequently on the sensorial attributes of the final product. This steep of freezing is carried out by a scraped surface heat exchanger (SSHE) where the product quality is conditioned by process conditions as the evaporation temperature of a refrigerant fluid, the mix flow rate, the dasher speed and the cylinder pressure due to the air introduction. In order to study the relevance of a control system based on the influence of process variables on product quality, this paper presents a model for a continuous crystallization of a sorbet using the method of moments, which is validated by experimental data.The model created by this methodology has been able to represent the influence of the process conditions during the crystallization of the sorbet on the final product characteristics such as crystal size and the draw temperature in the outlet of the SSHE in absence of air. The model based in moments is studied as a reduced model of the population balance equation and includes the phenomena of heterogeneous nucleation and growth. This model developed represents minimal computational requirements and is highly adapted for optimization and/or process control tasks.Peer Reviewe

RNAseq reveals different transcriptomic responses to GA3 in early and midseason varieties before ripening initiation in sweet cherry fruits

11openInternationalInternational coauthor/editorGibberellin (GA) negatively affects color evolution and other ripening-related processes in non-climacteric fruits. The bioactive GA, gibberellic acid (GA3), is commonly applied at the light green-to-straw yellow transition to increase firmness and delay ripening in sweet cherry (Prunus avium L.), though causing different effects depending on the variety. Recently, we reported that GA3 delayed the IAD parameter (a ripening index) in a mid-season variety, whereas GA3 did not delay IAD but reduced it at ripeness in an early-season variety. To further explore this contrasting behavior between varieties, we analyzed the transcriptomic responses to GA3 applied on two sweet cherry varieties with different maturity time phenotypes. At harvest, GA3 produced fruits with less color in both varieties. Similar to our previous report, GA3 delayed fruit color initiation and IAD only in the mid-season variety and reduced IAD at harvest only in the early-season variety. RNA-seq analysis of control- and GA3-treated fruits revealed that ripening-related categories were overrepresented in the early-season variety, including ‘photosynthesis’ and ‘auxin response’. GA3 also changed the expression of carotenoid and abscisic acid (ABA) biosynthetic genes in this variety. In contrast, overrepresented categories in the mid-season variety were mainly related to metabolic processes. In this variety, some PP2Cs putative genes were positively regulated by GA3, which are negative regulators of ABA responses, and MYB44-like genes (putative repressors of PP2Cs expression) were downregulated. These results show that GA3 differentially modulates the transcriptome at the onset of ripening in a variety-dependent manner and suggest that GA3 impairs ripening through the modification of ripening associated gene expression only in the early-season variety; whereas in the mid-season variety, control of the ripening timing may occur through the PP2C gene expression regulation. This work contributes to the understanding of the role of GA in non-climacteric fruit ripeningopenKuhn, N.; Maldonado, J.; Ponce, C.; Arellano, M.; Time, A.; Multari, S.; Martens, S.; Carrera, E.; Donoso, J.M.; Sagredo, B.; Meisel, L.A.Kuhn, N.; Maldonado, J.; Ponce, C.; Arellano, M.; Time, A.; Multari, S.; Martens, S.; Carrera, E.; Donoso, J.M.; Sagredo, B.; Meisel, L.A