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71.
72.
We estimate a production function that accounts for the economic performance of the country in the 20th century. We elaborate long term time series whereas most of the recent empirical studies on growth are based on cross section analysis. This approach allows us to follow the various regime changes that can be identified in the rich economic history of Argentina. To evaluate Total Factor Productivity (TFP) we initially test the classical Solow Model. We estimate the speed of convergence of TFP and obtain a non convergence result. This speed of convergence has declined since the 1930s, and we find a phenomenon of divergence in the period 1970–90. We then analyse the impact on production of additional variables recently highlighted in the endogenous growth literature such as the process of catch up of foreign technical progress, human capital and trade openness. Chow tests for this extended production function give us a strong probability of changes in the growth regimes. The estimation, that takes into consideration the break points identified, shows that the impact of trade openness and foreign technology is not stable throughout the century. In what concerns the impact of education on economic growth, we find a strong effect of primary education on growth, and a weaker effect of secondary-university education.  相似文献   
73.
In this paper, we introduce a Bayesian Analysis for the Block and Basu bivariate exponential distribution using Markov Chain Monte Carlo (MCMC) methods and considering lifetimes in presence of covariates and censored data. Posterior summaries of interest are obtained using the popular WinBUGS software. Numerical illustrations are introduced considering a medical data set related to the recurrence times of infection for kidney patients and a medical data set related to bone marrow transplantation for leukemia.  相似文献   
74.
We revisit the sequential search problem by Hey (J Econ Behav Organ 8:137–144, 1987). In a 2 \(\times \) 2 factorial design, varying fixed and random cost treatments with and without recall, we address open research questions that were originally stated by Hey (1987). Our results provide clear evidence for Hey’s (1987) conjecture that recall negatively affects performance in sequential search. With experience, however, search behavior with and without recall converges toward the optimal reservation rule. We further find that the utilization of optimal reservation rules is independent from the stochastic nature of the search cost.  相似文献   
75.
In this article, the authors first obtain the exact distribution of the logarithm of the product of independent generalized Gamma r.v.’s (random variables) in the form of a Generalized Integer Gamma distribution of infinite depth, where all the rate and shape parameters are well identified. Then, by a routine transformation, simple and manageable expressions for the exact distribution of the product of independent generalized Gamma r.v.’s are derived. The method used also enables us to obtain quite easily very accurate, manageable and simple near-exact distributions in the form of Generalized Near-Integer Gamma distributions. Numerical studies are carried out to assess the precision of different approximations to the exact distribution and they show the high accuracy of the approximations provided by the near-exact distributions. As particular cases of the exact distributions obtained we have the distribution of the product of independent Gamma, Weibull, Frechet, Maxwell-Boltzman, Half-Normal, Rayleigh, and Exponential distributions, as well as the exact distribution of the generalized variance, the exact distribution of discriminants or Vandermonde determinants and the exact distribution of any linear combination of generalized Gumbel distributions, as well as yet the distribution of the product of any power of the absolute value of independent Normal r.v.’s.  相似文献   
76.
In the context of local interpolators, radial basis functions (RBFs) are known to reduce the computational time by using a subset of the data for prediction purposes. In this paper, we propose a new distance-based spatial RBFs method which allows modeling spatial continuous random variables. The trend is incorporated into a RBF according to a detrending procedure with mixed variables, among which we may have categorical variables. In order to evaluate the efficiency of the proposed method, a simulation study is carried out for a variety of practical scenarios for five distinct RBFs, incorporating principal coordinates. Finally, the proposed method is illustrated with an application of prediction of calcium concentration measured at a depth of 0–20 cm in Brazil, selecting the smoothing parameter by cross-validation.  相似文献   
77.
Chair yoga (CY), a mind-body therapy, is a safe nonpharmacological approach for managing osteoarthritis (OA) in older adults who cannot participate in standing exercise. However, there is no linguistically tailored CY program for those with limited English proficiency (LEP). This 2-arm randomized controlled trial compared the effects of a linguistically tailored yoga program (English and Spanish versions) on the outcomes of pain, physical function, and psychosocial factors compared to the effects of a linguistically tailored Health Education Program (HEP; English and Spanish versions). Participants with lower-extremity OA, recruited from 2 community sites, completed the Spanish (n = 40) or English (= 60) version of twice-weekly 45-min CY or HEP sessions for 8 weeks. Data were collected at baseline, 4 weeks, 8 weeks, and 1- and 3-month follow-ups. English and Spanish CY groups (but neither HEP language group) showed significant decreases in pain interference. Measures of OA symptoms, balance, depression, and social activities were not significantly different between English and Spanish versions of CY and English and Spanish versions of HEP. It was concluded that the Spanish and English versions of CY and HEP were equivalent. Linguistically tailored CY could be implemented in aging-serving communities for persons with LEP.  相似文献   
78.
This article addresses the following questions: (a) How common is child abuse among domestically violent families? (b) Are there specific patterns of child abuse among domestically violent families? (c) What may explain occurrences of child abuse in domestically violent families? (d) How might domestic violence affect treatment for child abuse? We review research on child abuse in the context of domestic violence. We discuss implications of this research for service-delivery programs for domestically violent families.  相似文献   
79.
In the context of increasing demands for social and financial accountability of universities, the required implementation of transparent faculty evaluation systems constitutes a challenge and an opportunity for universities strategically aligning the activity of academic staff with the university goals. However, despite growing interest in the performance appraisal of faculty, only a few reported studies propose models that cover the full range of academic activities and the models in use are typically based on ad hoc scoring systems that lack theoretical soundness. This article approaches faculty evaluation from an innovative comprehensive perspective. Based on the concepts and methods of multiple criteria value measurement, it proposes a new faculty evaluation model that addresses the whole range of academic activities and can be applied within and across distinct scientific areas, while respecting their specificities. Constructed through a socio-technical process, the model was designed for and adopted by the Instituto Superior Técnico, the engineering school of the Technical University of Lisbon. The model has a two-level hierarchical additive structure, with top-level evaluation areas specified by second-level evaluation criteria. A bottom non-additive third level accounts for the quantitative and qualitative dimensions of academic activity related to each evaluation criterion. The model allows (a) the comparison of the performance of academic staff with performance targets reflecting the strategic policy concerns of university management; (b) the definition of the multicriteria value profile of each faculty member at the top level of the evaluation areas; (c) the computation of an overall value score for each faculty member, through an optimisation procedure that makes use of a flexible system of weights and (d) the assignment of faculty members to rating categories.  相似文献   
80.
In parallel with the development of credit derivatives market, researchers have begun to explore the relationship between Credit Default Swap (CDS) market and rating events. Many papers, via classical event-study methodology, show that CDS market is able to signal future negative rating events announced by credit rating agencies. In this work, we incorporate into the event-study methodology the ability of Markov switching models in modeling state-dependent means and variances. This approach allows to get over the drawbacks of the classical methodology, which ignores the heteroscedasticity and volatility clustering often affecting financial time series. The proposed methodology is applied to study the reactions of CDS quotes to reviews for downgrading and effective downgradings announced by the three major credit rating agencies (Fitch Ratings, Moody’s, Standard and Poor’s), in order to examine if and to what extent CDS market anticipates announcements related with a company’s creditworthiness. The analysis, focusing mainly on volatility, is performed on two periods, 2004–2006 and 2007–2009, in order to verify whether a change in the signaling power of CDS quotes can be ascribed to recent financial turmoils.  相似文献   
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