6,181 research outputs found
The Szeg\"o curve and Laguerre polynomials with large negative parameters
We study the asymptotic zero distribution of the rescaled Laguerre
polynomials, , with the parameter
varying in such a way that . The connection with the so-called Szeg\"{o} curve will
be showed
Climate Change Impacts on Maize and Dry Bean Yields of smallholder farmers in Honduras
The rotation maize and dry bean provides the main food supply of smallholder farmers in Honduras. Crop model assessment of climate change impacts (2070?2099 compared to a 1961?1990 baseline) on a maize?dry bean rotation for several sites across a range of climatic zones and elevations in Honduras. Low productivity systems, together with an uncertain future climate, pose a high level of risk for food security. The cropping systems simulation dynamic model CropSyst was calibrated and validated upon field trail site at Zamorano, then run with baseline and future climate scenarios based upon general circulation models (GCM) and the ClimGen synthetic daily weather generator. Results indicate large uncertainty in crop production from various GCM simulations and future emissions scenarios, but generally reduced yields at low elevations by 0 % to 22 % in suitable areas for crop production and increased yield at the cooler, on the hillsides, where farming needs to reduce soil erosion with conservation techniques. Further studies are needed to investigate strategies to reduce impacts and to explore adaptation tactics
Credit risk measurement under Basel II : an overview and implementation issues for developing countries
The objective of this paper is to provide an overview of the changes in the calculation of minimum regulatory capital requirements for credit risk that have been drafted by the Basel Committee on Banking Supervision (Basel II). Even though the revised credit capital rules represent a dramatic change compared to Basel I, it is shown that Basel II merely seeks to codify (albeit incompletely) existing good practices in bank risk measurement. However, its effective implementation in many developing countries is hindered by fundamental weaknesses in financial infrastructure that will need to be addressed as a priority.Banks&Banking Reform,Banking Law,Insurance&Risk Mitigation,Financial Intermediation,Economic Theory&Research
Asymptotically extremal polynomials with respect to varying weights and application to Sobolev orthogonality
9 pages, no figures.-- MSC2000 code: 33C45.MR#: MR2431543 (2009g:41009)Zbl#: Zbl 1155.33006We study the asymptotic behavior of the zeros of a sequence of polynomials whose weighted norms, with respect to a sequence of weight functions, have the same th root asymptotic behavior as the weighted norms of certain extremal polynomials. This result is applied to obtain the (contracted) weak zero distribution for orthogonal polynomials with respect to a Sobolev inner product with exponential weights of the form eâÏ(x), giving a unified treatment for the so-called Freud (i.e., when Ï has polynomial growth at infinity) and Erdös (when Ï grows faster than any polynomial at infinity) cases. In addition, we provide a new proof for the bound of the distance of the zeros to the convex hull of the support for these Sobolev orthogonal polynomials.Research by first two authors (C.D.M. and R.O.) was partially supported by DirecciĂłn General de InvestigaciĂłn, Ministerio de Ciencia y TecnologĂa of Spain, under grants MTM2005-08571 and
MTM2007-68114. Research by third author (H.P.) was partially supported by DirecciĂłn General de InvestigaciĂłn, Ministerio de Ciencia y TecnologĂa of Spain, under grant MTM2006-13000-C03-02, by Comunidad de Madrid-Universidad Carlos III de Madrid, under grants CCG06-UC3M/EST-0690 and CCG07-UC3M/ESP-3339, by Centro de InvestigaciĂłn
MatemĂĄtica de Canarias (CIMAC) and by Vicerrectorado de InvestigaciĂłn de La Universidad de La Laguna: Convocatoria 2005 de Ayudas a Profesores Invitados.Publicad
Optimal Allocation of Energy Storage and Wind Generation in Power Distribution Systems
The advent of energy storage technologies applications for the electric power system gives new tools for planners to cope with the operation challenges that come from the integration of renewable generation in medium voltage networks. This work proposes and implements an optimization model for Battery Energy Storage System (BESS) and distributed generation allocation in radial distribution networks. The formulation aims to assist distribution system operators in the task of making decisions on energy storage investment, BESSs\u27 operation, and distributed generation penetration\u27s level to minimize electricity costs. The BESSs are required to participate in energy arbitrage and voltage control. In addition, due to the complexity of the model formulated, a genetic algorithm combined with an AC multi-period optimal power flow implementation is used to solve the problem. The methodology provides the optimal connection points and size of a predetermined number of BESSs and wind generators, and the BESS\u27s operation. The model considers the BESSs\u27 charging/discharging efficiency, depth of discharge level, and the network\u27s operation constraints on the nodal voltage and branches power flow limits. The proposed methodology was evaluated in the IEEE 33-bus system. The results show that BESSs investment in radial distribution systems facilitates the deployment of distributed generation and favors the reduction of generation costs despite its still high capital cost.
Adviser: Fred Choobine
Failing and Merging as Competing Alternatives during Times of Financial Distress: Evidence from the Colombian Financial Crisis
This paper studies the determinants of individual bank failures and M&A processes in Colombia during the financial crisis of the late 1990s. Using bank-specific data we estimate competing risk hazards models and find that while profitability and capitalization are the most important determinants of the probability of failing, bankÂŽs size, efficiency and capitalization are the main determinants of the probability of participating in an integration process. All else constant, an increase in capitalization reduces the probability of disappearing, whether due to the occurrence of bankruptcy, a merge or an acquisition. However, a marginal increase in capitalization reduces significantly more the probability of bankruptcy than the probability of integration. This study is the first to present a competing risks hazard model to identify covariates that excerpt significant influence on the probability of failing or merging for banks of an emerging economy.Survival analysis; Competing risk models; Colombia. Classification JEL: G21; G33; G33; C25
The typology of partial credit guarantee funds around the world
This paper presents data on 76 partial credit guarantee schemes across 46 developed and developing countries. Based on theory, the authors discuss different organizational features of credit guarantee schemes and their variation across countries. They focus on the respective role of government and the private sector and different pricing and risk reduction tools and how they are correlated across countries. The findings show that government has an important role to play in funding and management, but less so in risk assessment and recovery. There is a surprisingly low use of risk-based pricing and limited use of risk management mechanisms.
- âŠ