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61.
In the poverty analysis framework, a great deal of attention has been paid to the poverty measurement in terms of monetary variables, such as income or consumption. In this context, a relevant open problem is connected with the distinction between poor and non-poor. In fact, the concept of poverty is rather vague and cannot be defined in a clear way. In this respect, following a fuzzy logic approach, some new poverty measures are proposed. In particular, the fuzzy extension of two existing poverty measures based on the Gini and Bonferroni inequality indices is provided. Some synthetic and real applications are given in order to show how the proposed poverty measures work.  相似文献   
62.
Hierarchical partition models (see Malec and Sedransk, 1992, Consonni and Veronese, 1995) aim at finding an optimal grouping (partition) of a set of experiments regarding a target variable. In this class of models the partition is regarded as an unknown parameter, and one of the main goals is computing the posterior distribution over the class of the possible partitions. This problem has been addressed in Sampietro and Veronese (1998), where a Metropolis-Hastings algorithm is applied. In this paper the performance of an alternative procedure, based on the logic of genetic algorithms, is evaluated. The results of the two approaches are compared, even if a conjoint use of them is to be advised.  相似文献   
63.
The authors use a Berry-Esseen type bound to identify the factors which influence the speed of convergence to the normal distribution of the indices of Gini, Piesch and Mehran. To empirically confirm the conclusions reached, a Monte Carlo experiment is performed for a log-logistic distribution.  相似文献   
64.
This article discusses an approach to the application of technological forecasting among a group of Italian companies. The information upon which the article is based has been obtained from a preliminary study. However, it should prove of interest to manufacturing organizations where similar problems necessitate a constructive approach to forecasting.  相似文献   
65.
This paper examines the relationship between the firm's direct ties, its inter‐firm network prominence and its likelihood of being acquired. The authors argue that firm's direct ties and prominence enhance the firm's visibility and signal its quality – and thus foster the firm's likelihood of being acquired. However, higher levels of direct ties and prominence, by providing access to resources and the firm's status, respectively, increase the firm's ability to remain independent and thus reduce its likelihood of being acquired. Thus, the authors posit the overall relation as an inverted U‐shaped. Furthermore, they show that, for firms that undergo an initial public offering, the aforementioned relation becomes much weaker. The hypotheses are empirically tested in the biopharmaceutical industry and important theoretical and managerial implications are discussed.  相似文献   
66.
67.
Abstract

Erectile dysfunction, prostatic hyperplasia and lower urinary tract symptoms hare important pathogenetic links. Endothelial dysfunction and hormonal alterations represent the main aspects. The present article examines the anatomical, physiological, and pathophysiological characteristics of this association, finalizing the text to an interpretation of the clinical management of these patients based on these functional considerations.  相似文献   
68.
Abstract

This article summarizes years of challenging research on erectile dysfunction (ED), a condition that has an important social and cultural relevance. Preclinical and clinical research progress has led to new therapeutic approaches to ED in patients with different comorbidities and particularly in those with low urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH). These goals were possible only by combined work of specialists and researchers of different and intertwined medical disciplines. Currently, tadalafil (5?mg/d) is the best choice; other phosphodiesterase-5 inhibitors (PDE5i) are not included among options, despite the growing evidence of therapeutic effects. Different regimens of tadalafil may be prescribed based on patient needs, severity of LUTS/BPH – ED profile, and clinical experience. An integrated approach is necessary to choose for a combined therapy with PDE5i and α-blockers following urological and cardiac counseling in terms of outcomes and adverse effects.  相似文献   
69.
Stricter laws require more incisive and costlier enforcement. Because enforcement activity depends both on available tax revenue and the honesty of officials, the optimal legal standard of a benevolent government is increasing in per capita income and decreasing in officials' corruption. In contrast to the “tollbooth view” of regulation, the standard chosen by a self‐interested government is a non‐monotonic function of officials' corruption, and can be either lower or higher than that chosen by a benevolent regulator. International evidence on environmental regulation shows that standards correlate positively with per‐capita income, and negatively with corruption, consistent with the model's predictions for benevolent governments. (JEL: D73, K42, L51)  相似文献   
70.
Summary.  Clinical trials of micronutrient supplementation are aimed at reducing the risk of infant mortality by increasing birth weight. Because infant mortality is greatest among the low birth weight (LBW) infants (2500 g or under), an effective intervention increases the birth weight among the smallest babies. The paper defines population and counterfactual parameters for estimating the treatment effects on birth weight and on survival as functions of the percentiles of the birth weight distribution. We use a Bayesian approach with data augmentation to approximate the posterior distributions of the parameters, taking into account uncertainty that is associated with the imputation of the counterfactuals. This approach is particularly suitable for exploring the sensitivity of the results to unverifiable modelling assumptions and other prior beliefs. We estimate that the average causal effect of the treatment on birth weight is 72 g (95% posterior regions 33–110 g) and that this causal effect is largest among the LBW infants. Posterior inferences about average causal effects of the treatment on birth weight are robust to modelling assumptions. However, inferences about causal effects for babies at the tails of the birth weight distribution can be highly sensitive to the unverifiable assumption about the correl-ation between the observed and the counterfactuals birth weights. Among the LBW infants who have a large causal effect of the treatment on birth weight, we estimate that a baby receiving the treatment has 5% less chance of death than if the same baby had received the control. Among the LBW infants, we found weak evidence supporting an additional beneficial effect of the treatment on mortality independent of birth weight.  相似文献   
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