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11.
Set up as a one-group pre-test–post-test follow-up design, this study examines the outcomes of intensive family preservation services (IFPS) in Flanders addressing the following research questions: Does IFPS make a significant difference concerning (1) the interaction between parent and child? (2) social support as experienced by the parent? (3) stress and empowerment of the parent? and (4) the strengths and difficulties of the minor? Families seem to indicate that their family situation is more manageable, although still, professional help is needed. Parents feel more resilient about the situation and indicate that they can get along with their child better than before the crisis intervention. Parents still feel uncertain about the future and about their role as a parent. There seems to be no indications that their level and quality of social contacts have changed. Further research is suggested to provide more in-depth information about the conditions associated with processes of change during an IFPS intervention.  相似文献   
12.
Linear vector autoregressive (VAR) models where the innovations could be unconditionally heteroscedastic are considered. The volatility structure is deterministic and quite general, including breaks or trending variances as special cases. In this framework we propose ordinary least squares (OLS), generalized least squares (GLS) and adaptive least squares (ALS) procedures. The GLS estimator requires the knowledge of the time-varying variance structure while in the ALS approach the unknown variance is estimated by kernel smoothing with the outer product of the OLS residual vectors. Different bandwidths for the different cells of the time-varying variance matrix are also allowed. We derive the asymptotic distribution of the proposed estimators for the VAR model coefficients and compare their properties. In particular we show that the ALS estimator is asymptotically equivalent to the infeasible GLS estimator. This asymptotic equivalence is obtained uniformly with respect to the bandwidth(s) in a given range and hence justifies data-driven bandwidth rules. Using these results we build Wald tests for the linear Granger causality in mean which are adapted to VAR processes driven by errors with a nonstationary volatility. It is also shown that the commonly used standard Wald test for the linear Granger causality in mean is potentially unreliable in our framework (incorrect level and lower asymptotic power). Monte Carlo experiments illustrate the use of the different estimation approaches for the analysis of VAR models with time-varying variance innovations.  相似文献   
13.
This paper addresses one neglected issue in the study of regional integration: the impact of a complex of transnational factors on a country’s development. Goods and productive factors move relatively unhindered and engender less visible (and quantifiable) linkages in the form of global value chains, regional productive clusters or social networks within areas of variable geometry. We refer to this regional partitioning that emerges in space and time within variable boundaries as a context of development. On the basis of this central premise, this study aims to contribute to the ongoing debate on the spatial complexity of economies with a mapping exercise delineating a self-supporting space for development. Paper’s key insight implies that development is informed as much by conventional tenets of economic theory as by new theses of social and cultural nature that makes the case for a space of development of variable geometry.  相似文献   
14.
Environmental emergency situations can differ in many ways, for instance according to their causes and the dimension of their impacts. Yet, they share the characteristic of sudden onset and the necessity for a coherent and effective emergency management. In this paper we consider decision support in the event of a nuclear or radiological accident in Europe. RODOS, an acronym for real-time on-line decision support system, is a decision support system designed to provide support from the early phases through to the medium and long-term phases. This work highlights the role of multi-criteria decision analysis (MCDA) within RODOS in ensuring the transparency of decision processes within emergency and remediation management. Special emphasis is placed on the evaluation of alternative remediation or countermeasure strategies using the multi-criteria decision support tool Web-HIPRE in scenario focused decision making workshops involving different stakeholder and expert groups. Decision support is enhanced by a module that generates natural language explanations to facilitate the understanding of the evaluation process, therefore contributing to the direct involvement of the decision makers, with the aim of increasing their confidence in the results of the analyses carried out, forming an audit trail for the decision making process and improving the acceptability of the system as a whole.  相似文献   
15.
Chebyshev's inequality and its generalizations make it possible to give upper bounds for the tail probabilities in the distribution of a random variable. We present a method of finding lower bounds for these probabilities . The method is based on improvements of the Lyapunov inequality for moments of a random variable.  相似文献   
16.
There is no significant history of migration from Nepal to Denmark, but the post-conflict situation in Nepal and the expansion of an international, commercialised education market have resulted in a significant number of Nepalese students in Denmark. This article argues, first, that the current forms of student migration from Nepal must be examined within the context of broader class-based mobility practices and the consolidation of a relatively new middle-class in Nepal. Second, it examines the significance of education and educated status for people’s claims to belong to the middle-class in a transnational context where social status is at stake.  相似文献   
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18.
The A-optimality problem is solved for three treatments in a row–column layout. Depending on the numbers of rows and columns, the requirements for optimality can be decidedly counterintuitive: replication numbers need not be as equal as possible, and trace of the information matrix need not be maximal. General rules for comparing 3×33×3 information matrices for their A-behavior are also developed, and the A-optimality problem is also solved for three treatments in simple block designs.  相似文献   
19.
When a community or ecosystem is lost, some of its properties may remain, leaving behind an ecological memory. The soil properties, spores, seeds, stem fragments, mycorrhizae, species, populations and other remnants of the previous inhabitants contribute to shaping the replacement community and building a new ecosystem. The loss of ecological memory for the natural stability domain of a site reduces ecosystem resilience and enables alien invasive species to become established more easily. These invasives may eventually create a new ecosystem with its own ecological memory and resilience. These new ecosystems are described here as novel ecosystems and are placed in the context of adaptive cycles. Ecological restoration of urban ecosystems requires removing the ecological legacy of invasive alien species. To be successful, invasive species control must address both internal within patch memory of invasives and external between patch memory. The restoration of Garry oak ecosystems (Quercus garryana), by students of the Restoration of Natural Systems Program at the University of Victoria, British Columbia, and a number of other examples are presented here that highlight why ecological memory is especially important in urban ecosystems.  相似文献   
20.
On Testing Equality of Distributions of Technical Efficiency Scores   总被引:5,自引:0,他引:5  
The challenge of the econometric problem in production efficiency analysis is that the efficiency scores to be analyzed are unobserved. Statistical properties have recently been discovered for a type of estimator popular in the literature, known as data envelopment analysis (DEA). This opens up a wide range of possibilities for well-grounded statistical inference about the true efficiency scores from their DEA estimates. In this paper we investigate the possibility of using existing tests for the equality of two distributions in such a context. Considering the statistical complications pertinent to our context, we consider several approaches to adapting the Li test to the context and explore their performance in terms of the size and power of the test in various Monte Carlo experiments. One of these approaches shows good performance for both the size and the power of the test, thus encouraging its use in empirical studies. We also present an empirical illustration analyzing the efficiency distributions of countries in the world, following up a recent study by Kumar and Russell (2002), and report very interesting results.  相似文献   
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