欧洲治理的不同路径及其对国家制度的影响

欧盟国家制度变迁及国家间趋同的潜能随着所运用的特定治理模式的改变而变化。这些模式可分为以下三种:一、服从对国家执行机关具有法律约束力的欧盟规章;二、不同国家管理体制之间为达到欧盟要求展开竞争;三、跨国层面的监管机构在欧盟法律或制度架构内进行沟通。国家官僚机构做出应对的行为理性包括:持续驱动、结果驱动和合法性驱动。国家变迁程度和方向上存在着某些矛盾,即一致的政治目标与实际趋同之间似乎是一种相反的关系:基于服从治理的政策,显然旨在使国家政策一致;而相对于接受国家多样化的斗争和沟通治理路径而言,却对国内制度趋同的推动力不那么明显。     

Pattern–mixture and selection models for analysing longitudinal data with monotone missing patterns

Summary. We examine three pattern–mixture models for making inference about parameters of the distribution of an outcome of interest Y that is to be measured at the end of a longitudinal study when this outcome is missing in some subjects. We show that these pattern–mixture models also have an interpretation as selection models. Because these models make unverifiable assumptions, we recommend that inference about the distribution of Y be repeated under a range of plausible assumptions. We argue that, of the three models considered, only one admits a parameterization that facilitates the examination of departures from the assumption of sequential ignorability. The three models are nonparametric in the sense that they do not impose restrictions on the class of observed data distributions. Owing to the curse of dimensionality, the assumptions that are encoded in these models are sufficient for identification but not for inference. We describe additional flexible and easily interpretable assumptions under which it is possible to construct estimators that are well behaved with moderate sample sizes. These assumptions define semiparametric models for the distribution of the observed data. We describe a class of estimators which, up to asymptotic equivalence, comprise all the consistent and asymptotically normal estimators of the parameters of interest under the postulated semiparametric models. We illustrate our methods with the analysis of data from a randomized clinical trial of contracepting women.