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"We estimate plant--level idiosyncratic risk in the U.S. manufacturing sector. Our proxy for risk is the volatility of the portion of TFP growth which is not explained by either industry- or economy-wide factors, or by establishments' characteristics systematically associated with growth itself. Consistent with previous studies, we find that idiosyncratic shocks are much larger than aggregate random disturbances, accounting for about 90% of the overall uncertainty faced by plants. The extent of cross-sectoral variation in idiosyncratic risk is remarkable. Plants in the most volatile sector are subject to at least three times as much uncertainty as plants in the least volatile. Our evidence indicates that idiosyncratic risk is higher in industries where the extent of creative destruction is likely to be greater"--National Bureau of Economic Research web site

AbstractWe study the aggregate productivity effects of firm‐level financial frictions. Credit constraints affect not only production decisions but also household‐level schooling decisions. In turn, entrepreneurial schooling decisions impact firm‐level productivities, whose cross‐sectional distribution becomes endogenous. In anticipation of future constraints, entrepreneurs underinvest in schooling early in life. Frictions lower aggregate productivity because talent is misallocated across occupations and capital is misallocated across firms. Firm‐level productivities are also lower due to schooling distortions. These effects combined account for between 36% and 68% of the US–India aggregate productivity difference. Schooling distortions are the major source of aggregate productivity differences.

In Portugal, the last decade has been characterised by important reforms in the educational system particularly of secondary education. The Portuguese Language Area, comprising different subjects, was submitted to deep changes concerning its aims, content, methodologies, and assessment. In this paper, it is my purpose to analyse some of those changes, focusing on their underlying principles, their main features and their impact both in the pedagogic field and in the public sphere. I consider firstly the political and educational circumstances in which the reconfiguration of the Portuguese Language Area in secondary education took place. Then, I proceed to describe the main features of the official pedagogic discourse that gives expression to such reconfiguration through an examination of the Portuguese Language Syllabus. After that, school textbooks are focused on, in order to understand how they interpret the official discourse and how they conceive pedagogic practice. Subsequently, as a means to capture continuities and discrepancies between pedagogic and public spheres, the analysis deals with a corpus of texts from the media that give voice to positions concerning the teaching of Portuguese. In the last section, according to the analysis previously developed, I discuss the tensions that lie across the Portuguese Language Area and that will probably regulate the directions of its development. ...

It is the aim of several European governments to develop private insurance markets on the top of public health insurance plans. We look at the effects of tax exemptions as an instrument for inducing individuals to opt out. Tax exemptions on private insurance premiums are shown to be instruments having a substantial degree of uncertainty in their effects. On the other hand, tax waivers based on per capita medical spending to lead individuals (mainly good health risks) to opt out from the social program. This accompanied by an overall increase in state spending (and taxes) due to transfers which must be made, and by an income redistribution effect from bad risks to good risks. ; N/A

The 2001/77/CE Renewable Energies European Directive together with Kyoto Protocol ratification supported by a Government vision and strong objective on the reduction of external oil dependence put Portugal in the front line to achieve one of the highest wind energy penetrations within ten years time. This paper gives a summarized overview of the Portuguese technical approaches and methodologies followed in order to plan and accomodate the ambitious wind power goals to 2010/2013, preserving the overall quality of the power system.

The 2001/77/CE Renewable Energies European Directive together with Kyoto Protocol ratification supported by a government vision and strong objective on the reduction of external oil dependence put Portugal in the front line to achieve one of the highest wind energy penetrations within 10 years$1 (B time. This paper gives a summarized overview of the Portuguese technical approaches and methodologies followed in order to plan and accommodate the ambitious wind power goals to 2010/2013, preserving the overall quality of the power system.

This paper presents a decision support model for negotiation portfolio optimization considering the participation of players in local markets (at the microgrid level) and in external markets, namely in regional markets, wholesale negotiations and negotiations of bilateral agreements. A local internal market model for microgrids is defined, and the connection between interconnected microgrids is based on nodal pricing to enable negotiations between nearby microgrids. The market environment considering the local market setting and the interaction between integrated microgrids is modeled using a multi-agent approach. Several multi-agent systems are used to model the electricity market environment, the interaction between small players at a microgrid scale, and to accommodate the decision support features. The integration of the proposed models in this multi-agent society and interaction between these distinct specific multi-agent systems enables modeling the system as a whole and thus testing and validating the impact of the method in the outcomes of the involved players. Results show that considering the several negotiation opportunities as complementary and making use of the most appropriate markets depending on the expected prices at each moment allows players to achieve more profitable results. ; This work has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 703689 (project ADAPT). Rui Castro was supported by national funds through FCT with reference UID/CEC/50021/201; Mohammad Ali Fotouhi Ghazvini has been supported by PhD grant reference SFRH/BD/94688/2013. ; info:eu-repo/semantics/publishedVersion