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961.
We join the authors in this special issue in their call to embrace a culture of evaluation. Obstacles to change are formidable. Educators debate their purpose – provide knowledge or achieve environmental goals – and we have limited evidence of the effectiveness of environmental programs and policies. Change requires collaboration across organizations and disciplines, targeted capacity building, and building systems of assessment into programs that enable more sophisticated evaluations. As in other fields, an evidence-based movement will increase the credibility and effectiveness of environmental education. A culture of evaluation offers educators a solid platform to collaboratively and efficiently achieve society's environmental goals. 相似文献
962.
The mutual influence of smoking behavior and friendships in adolescence is studied. It is attempted to disentangle influence and selection processes in reciprocal and non-reciprocal friendships. An actor-based model is described for the co-evolution of friendship networks and smoking behavior. This model considers alternative selection and influence mechanisms, and models continuous-time changes in network and behavior. The data consists of a longitudinal sample of 1326 Finnish adolescents in 11 high schools. Findings suggest that selection as well as influence processes play an important role in adolescent smoking behavior. Selection had a relatively stronger role than influence, in particular when selecting non-reciprocal friends. The strength of both influence and selection processes decreased over time. 相似文献
963.
The farmers' role within the EU has recently been under reconstruction: in addition to primary agricultural production farmers should fulfil multiple functions such as maintaining the rural landscape, conserving nature and providing services. One essential feature of this new role is the demand for entrepreneurship. Farmers should be capable of competing in the worldwide, global agricultural market. They are also encouraged to diversify into business activities beyond agriculture. How do farmers see themselves in this situation? Is their self-perception compatible with this new reconstruction of the farming economy and the farmers' role? Research, thus far, seems to indicate that traditional or production oriented identities are still dominant among farmers. But there is also some evidence that new identities, such as the entrepreneurial identity, are emerging. In our study we are especially interested in how Finnish farmers have met the demand for adapting to the role of an entrepreneur. We approach the issue of the farmers' changing role from a social psychological perspective by utilizing the concept of identity. Our empirical evidence comes from two nation-wide postal questionnaire data sets, both containing samples from three subgroups: conventional farmers focusing solely on primary agricultural production, diversified farmers who also had other business besides agricultural production, and rural non-agricultural small-scale businesses. The results show that Finnish farmers do not experience “entrepreneur” as something distant from themselves and as not fitting in with their world of ideas, as the work of some researchers would depict. Instead, the majority of Finnish farmers, especially diversified farmers, conceive of themselves both as entrepreneurs and as producers. 相似文献
964.
965.
T. C. EDWIN CHENG CHELLIAH SRISKANDARAJAH GUOQING WANG 《Production and Operations Management》2000,9(4):367-378
In this paper we study the time complexities of some two‐ and three‐stage no‐wait flowshop makespan scheduling problems where, in some stage, all the jobs require a constant processing time and the stage may consist of parallel identical machines. Polynomial time algorithms are presented for certain problems, while several others are proved to be strongly NP‐complete. 相似文献
966.
Mohammad Z. Raqab Mohamed T. Madi 《Journal of statistical planning and inference》2011,141(10):3313-3322
In this paper, and based on a progressive type-II censored sample from the generalized Rayleigh (GR) distribution, we consider the problem of estimating the model parameters and predicting the unobserved removed data. Maximum likelihood and Bayesian approaches are used to estimate the scale and shape parameters. The Gibbs and Metropolis samplers are used to predict the life lengths of the removed units in multiple stages of the progressively censored sample. Artificial and real data analyses have been performed for illustrative purposes. 相似文献
967.
Yong Zhou Alan T.K. Wan Yuan Yuan 《Journal of statistical planning and inference》2011,141(12):3814-3828
Least-squares and quantile regressions are method of moments techniques that are typically used in isolation. A leading example where efficiency may be gained by combining least-squares and quantile regressions is one where some information on the error quantiles is available but the error distribution cannot be fully specified. This estimation problem may be cast in terms of solving an over-determined estimating equation (EE) system for which the generalized method of moments (GMM) and empirical likelihood (EL) are approaches of recognized importance. The major difficulty with implementing these techniques here is that the EEs associated with the quantiles are non-differentiable. In this paper, we develop a kernel-based smoothing technique for non-smooth EEs, and derive the asymptotic properties of the GMM and maximum smoothed EL (MSEL) estimators based on the smoothed EEs. Via a simulation study, we investigate the finite sample properties of the GMM and MSEL estimators that combine least-squares and quantile moment relationships. Applications to real datasets are also considered. 相似文献
968.
This continuing education course for professionals involved in all areas of clinical trials integrates concepts related to the role of randomization in the scientific process. The course includes two interactive lecture and discussion sections and a workshop practicum. The first interactive lecture introduces basic clinical trial issues and statistical principles such as bias, blinding, randomization, control groups, and the importance of formulating clear and discriminating clinical and statistical hypotheses. It then focuses on the most commonly used clinical study designs and the corresponding patient randomization schemes. The second interactive lecture focuses on the implementation of randomization of patients and drug supply through allocation and component ID schedules. The workshop practicum, conducted in small groups, enables students to apply the lecture concepts to real clinical studies. Flexibility was built into the workshop practicum materials to allow the course content to be customized to specific audiences, and the interactive lecture sessions can be stretched to cover more advanced topics according to class interest and time availability. 相似文献
969.
970.
Despite employment being consistently identified as a key factor in successful refugee resettlement, people from refugee backgrounds in Aotearoa New Zealand are overrepresented in unemployment statistics. Of those who do gain employment, few secure work that is adequately remunerated and commensurate with the person's skills and qualifications. This paper explores whether the two recent government-driven initiatives, the welfare reforms and the New Zealand Refugee Resettlement Strategy, provide an opportunity to address these issues. Based on previous research, the authors identify the main employment barriers facing people from refugee backgrounds. They argue that while the welfare reforms and the Refugee Resettlement Strategy are underpinned by a desire to see more people in employment, for real change to occur, an integrated holistic approach is needed. This approach needs to include additional resourcing for government-funded specialist one-on-one employment programmes that are available in all regions where refugees are resettled. These programmes combined with access to fully funded English language tuition and work experience and internship opportunities would help reduce the barriers people from refugee backgrounds face when seeking employment. 相似文献