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21.
Dekker Paul 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2019,30(1):74-85
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - This contribution about the Netherlands to the special issue [or: section] on volunteering and civic action focuses on... 相似文献
22.
Rianne Kloosterman Stijn Ruiter Paul M. de Graaf Gerbert Kraaykamp 《The British journal of sociology》2009,60(2):377-398
According to Boudon, social background affects educational transitions as a result of differences in children's academic performance (primary effects) and differences in transition probabilities given children's level of academic performance (secondary effects). This study addresses historical changes in both primary and secondary effects on the educational transition from primary school to higher secondary education in the Netherlands. In addition, it considers changes over time in the relative importance of these effects. The study compares five cohorts of Dutch pupils, specifically those enrolling in secondary education in 1965, 1977, 1989, 1993 and 1999, and it employs counterfactual analyses. The main findings are that secondary effects have been stable and primary effects have fluctuated to some extent. As a result, the proportion of the total effect of social background accounted for by primary effects has increased somewhat, from 53 per cent to 58 per cent. 相似文献
23.
The majority of after‐sales service providers manage their service parts inventory by focusing on the availability of service parts. This approach, combined with automatic replenishment systems, leads to reactive inventory control policies where base stock levels are adjusted only after a service contract expires. Consequently, service providers often face excess stock of critical service parts that are difficult to dispose due to their specificity. In this study, we address this problem by developing inventory control policies taking into account contract expirations. Our key idea is to reduce the base stock level of the one‐for‐one policy before obsolescence (a full or partial drop in demand rate) occurs and let demand take away excess stock. We refer to this policy as the single‐adjustment policy. We benchmark the single‐adjustment policy with the multiple‐adjustment policy (allowing multiple base stock adjustments) formulated as a dynamic program and verify that for a wide range of instances the single‐adjustment policy is an effective heuristic for the multiple‐adjustment policy. We also compare the single‐adjustment policy with the world‐dependent base stock policy offered by Song and Zipkin (1993) and identify the parameter combinations where both policies yield similar costs. We consider two special cases of the single‐adjustment policy where the base stock level is kept fixed or the base stock adjustment is postponed to the contract expiration time. We find that the initial demand rate, contract expiration time, and size of the drop in demand rate are the three key parameters driving the choice between the single‐adjustment policy and its special cases. 相似文献
24.
Rianne Margaretha Schouten Peter Lugtig Gerko Vink 《Journal of Statistical Computation and Simulation》2018,88(15):2909-2930
Missing data form a ubiquitous problem in scientific research, especially since most statistical analyses require complete data. To evaluate the performance of methods dealing with missing data, researchers perform simulation studies. An important aspect of these studies is the generation of missing values in a simulated, complete data set: the amputation procedure. We investigated the methodological validity and statistical nature of both the current amputation practice and a newly developed and implemented multivariate amputation procedure. We found that the current way of practice may not be appropriate for the generation of intuitive and reliable missing data problems. The multivariate amputation procedure, on the other hand, generates reliable amputations and allows for a proper regulation of missing data problems. The procedure has additional features to generate any missing data scenario precisely as intended. Hence, the multivariate amputation procedure is an efficient method to accurately evaluate missing data methodology. 相似文献
25.
A Local Dimension of Integration Policies? A Comparative Study of Berlin,Malmö, and Rotterdam
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Rianne Dekker Henrik Emilsson Bernhard Krieger Peter Scholten 《The International migration review》2015,49(3):633-658
This study examines three theses on local integration policies by a qualitative comparative case study of integration policies in three cities in three different countries (Berlin, Malmö, and Rotterdam). We found little evidence of a congruent local dimension of integration policies. Local policies resemble their national policy frameworks fairly well in terms of policy approaches and domains. Our multi‐level perspective shows that this is not the result of top‐down hierarchical governance, but rather of a multilevel dynamic of two‐way interaction. Local policy legacies and local politics matter and national policies are also influenced by local approaches of integration. 相似文献
26.
Rianne Honigh-de Vlaming Annemien Haveman-Nies Inge Bos-Oude Groeniger Eveline J. C. Hooft van Huysduynen Lisette C. P. G. M. de Groot Pieter van’t Veer 《Social indicators research》2014,116(3):989-1001
To develop and evaluate the Loneliness Literacy Scale for the assessment of short-term outcomes of a loneliness prevention programme among Dutch elderly persons. Scale development was based on evidence from literature and experiences from local stakeholders and representatives of the target group. The scale was pre-tested among 303 elderly persons aged 65 years and over. Principal component analysis and internal consistency analysis were used to affirm the scale structure, reduce the number of items and assess the reliability of the constructs. Linear regression analysis was conducted to evaluate the association between the literacy constructs and loneliness. The four constructs “motivation”, “self-efficacy”, “perceived social support” and “subjective norm” derived from principal component analysis captured 56 % of the original variance. Cronbach’s coefficient α was above 0.7 for each construct. The constructs “self-efficacy” and “perceived social support” were positively and “subjective norm” was negatively associated with loneliness. To our knowledge this is the first study developing a short-term indicator for loneliness prevention. The indicator contributes to the need of evaluating public health interventions more close to the intervention activities. 相似文献
27.
Dekker Paul van den Broek Andries 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》1998,9(1):11-38
Involvement in voluntary associations is analyzed from the perspective of questions raised in the debate about civil society. After demarcating the concept of civil society in relation to the community, the market, and the state, expectations are formulated about the negative effects of modernization and individualization on volunteering and the positive effects of volunteering on social capital and public discourse. World Values 1990 data are used for inter- and intranational analyses. Neither rankings of thirteen Western nations nor in-depth analyses of the U.S., the Netherlands, and Italy support worried reflections about the effects of modernization. The Idea that involvement in voluntary associations is conducive to social cohesion and political democracy finds empirical support. Both mere membership of an association and actual volunteering within such an association appear to be important in this respect. 相似文献
28.
Workforce size and work-related role stress 总被引:1,自引:0,他引:1
This paper examines the relationships between workforce size and four work-role stressors, along with two variables that are proposed here to mediate these relationships: objective organizational support and perceived organizational support. A total of 112 clerical workers in organizations of 1-500 employees participated in the study. Workforce size was positively associated with role ambiguity, role conflict, quantitative and qualitative role overload, and objective organizational support; and it was negatively correlated with perceived organizational support. Partial correlations were then computed between workforce size and role stress, controlling sequentially for objective and perceived support. The relationships between workforce size and the four role stressors remained significant when objective support was controlled. However, the corresponding relationships were non-significant after partialling out the effects of perceived organizational support, which suggests that the effect of workforce size on role stressors is indirect, and a function of perceived organizational support. 相似文献
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Dekker Paul 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2021,32(3):709-710
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - 相似文献