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51.
Lower urinary tract symptoms (LUTS) secondary to benign prostatic obstruction (BPO) represent one of the most common clinical complaints in adult men. Several drugs used for LUTS/BPO may strongly affect sexual function and bother. The aim of this systematic review and meta-analysis was to evaluate the impact of combination therapy with alpha-blockers (AB), 5-alpha reductase inhibitors (5-ARI) on the risk of erectile dysfunction(ED) and libido alterations (LA) from randomized clinical trial (RCT). Based on the inclusion and exclusion criteria, five RCTs involving 6131 patients were included in the analysis. According to the analysis, the overall prevalence of ED and LA were significantly greater in the combination treatment group than in the AB group (7.93% versus 4.66%; OR 1.81; p?p?=?0.003, respectively). The combination therapy increased the risk of ED compared to monotherapy with 5-ARI (7.93% versus 6.47%; OR 1.25; p?=?0.04) but not the risk of LA (3.51% versus 3.37; OR 1.03; p?=?0.84). In our systematic meta-analysis, we demonstrated that combination therapy with ABs and 5-ARIs was associated with significantly higher risk of ED and LA compared with single monotherapy. Combination therapy showed similar risk of LA compared with 5-ARI monotherapy.  相似文献   
52.
Theory and Decision - Economics bases the choice theory on the mental experiment that introduces the choice correspondence, which associates to every set of possible actions the subset of preferred...  相似文献   
53.
The single-case design, with its potential integration of practice and research roles, has roots extending back to the “scientific charity” movement of the late 1800s. While the goals of “scientific charity” were never realized, the new research technology bears promise of achieving them. This background, together with the related experiences of behavioral psychology and of medicine, is briefly highlighted and the prospects, pitfalls, and challenges involved are discussed.  相似文献   
54.
Theory and Decision - Choice under uncertainty is treated in economics by different approaches. We can distinguish three of them, two of which concern individual choice, while the third frames...  相似文献   
55.
Emergency vaccination is an effective control strategy for foot‐and‐mouth disease (FMD) epidemics in densely populated livestock areas, but results in a six‐month waiting period before exports can be resumed, incurring severe economic consequences for pig exporting countries. In the European Union, a one‐month waiting period has been discussed based on negative test results in a final screening. The objective of this study was to analyze the risk of exporting FMD‐infected pig carcasses from a vaccinated area: (1) directly after final screening and (2) after a six‐month waiting period. A risk model has been developed to estimate the probability that a processed carcass was derived from an FMD‐infected pig (Pcarc). Key variables were herd prevalence (PH), within‐herd prevalence (PA), and the probability of detection at slaughter (PSL). PH and PA were estimated using Bayesian inference under the assumption that, despite all negative test results, ≥1 infected pigs were present. Model calculations indicated that Pcarc was on average 2.0 × 10?5 directly after final screening, and 1.7 × 10?5 after a six‐month waiting period. Therefore, the additional waiting time did not substantially reduce Pcarc. The estimated values were worst‐case scenarios because only viraemic pigs pose a risk for disease transmission, while seropositive pigs do not. The risk of exporting FMD via pig carcasses from a vaccinated area can further be reduced by heat treatment of pork and/or by excluding high‐risk pork products from export.  相似文献   
56.
We extend Kreps' (1979) analysis of preference for flexibility, reinterpreted by Kreps (1992) as a model of unforeseen contingencies. We enrich the choice set, consequently obtaining uniqueness results that were not possible in Kreps' model. We consider several representations and allow the agent to prefer commitment in some contingencies. In the representations, the agent acts as if she had coherent beliefs about a set of possible future (ex post) preferences, each of which is an expected‐utility preference. We show that this set of ex post preferences, called the subjective state space, is essentially unique given the restriction that all ex post preferences are expected‐utility preferences and is minimal even without this restriction. Because the subjective state space is identified, the way ex post utilities are aggregated into an ex ante ranking is also essentially unique. Hence when a representation that is additive across states exists, the additivity is meaningful in the sense that all representations are intrinsically additive. Uniqueness enables us to show that the size of the subjective state space provides a measure of the agent's uncertainty about future contingencies and that the way the states are aggregated indicates whether these contingencies lead to a desire for flexibility or commitment.  相似文献   
57.
Two goodness of fit statistics with asymmetric weight function are derived from a decomposition of the Anderson-Darling statistic, For each one, the asymptotic null distribution is found for a simple null hypothesis and some upper percentties are calculated. The asymptotic power of the tests are obtained for some contiguous alternatives around a normal null hypothesis. The tests allow the user to choose to which tail to give more weight and it is intended to be used for that purpose. Therefore it should be not considered as a competitor of the classical goodness of fit tests.  相似文献   
58.
Dekel, Lipman and Rustichini (2001) (henceforth DLR) axiomatically characterized three representations of preferences that allow for a desire for flexibility and/or commitment. In one of these representations (ordinal expected utility), the independence axiom is stated in a weaker form than is necessary to obtain the representation; in another (additive expected utility), the continuity axiom is too weak. In this erratum we provide examples showing that the axioms used by DLR are not sufficient, and provide stronger versions of these axioms that, together with the other axioms used by DLR, are necessary and sufficient for these two representations.  相似文献   
59.
The risk aversion measure without the independence axiom   总被引:1,自引:0,他引:1  
The risk premium (conveniently normalized) is defined as the measure of risk aversion. This measure does not require any relevant assumption in the theory of choice under uncertainty except the existence of a certainty equivalent. In particular, the independence axiom is not required. The measure of risk aversion of an action is provided not only for the case with one commodity and two consequences but also for the case with many commodities and consequences. The measure of mean risk aversion of all actions with given consequences is introduced and the local measure of risk aversion is obtained by making all these consequences approach the consequence under consideration. This measure is demonstrated to be zero when the von Neumann-Morgenstern utility function exists. In this case a measure of risk aversion of the second order is introduced, which turns out to be equal to the Arrow-Pratt absolute index when there is only one commodity and similar to the generalized measures proposed by several authors when there are many commodities and two consequences.Helpful comments by I. Gilboa and suggestions by the referee are gratefully acknowledged.  相似文献   
60.
In this paper we discuss three types of ordered alternatives ordered location, stochastic ordering and quadrant dependence. We prove that quadrant dependence is the more general among the three. Then we consider a conditional tests for the equality of c distributions against quadrant dependence in a multivariate setup. An exact simultaneous testing procedure based on dependent conditional tests is presented. Two applications to real data are also given.  相似文献   
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