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941.
The period-based total fertility rate is probably the most commonly used single measure of a population??s fertility level, but it has the disadvantage that it only controls for the population??s age distribution and not for any other subdividing feature, such as the parity distribution, ethnic composition, or educational attainment. This may lead the TFR to change because the population composition changes, even when the underlying fertility remains constant in each population sub-group. In the present contribution, we use elementary event-history methods to show how one can easily control the TFR against a change in the population??s distribution across any selected subdivision. We use the data of the Romanian Gender and Generations Survey of 2005 to illustrate how this can be done.  相似文献   
942.
We consider Markov-switching regression models, i.e. models for time series regression analyses where the functional relationship between covariates and response is subject to regime switching controlled by an unobservable Markov chain. Building on the powerful hidden Markov model machinery and the methods for penalized B-splines routinely used in regression analyses, we develop a framework for nonparametrically estimating the functional form of the effect of the covariates in such a regression model, assuming an additive structure of the predictor. The resulting class of Markov-switching generalized additive models is immensely flexible, and contains as special cases the common parametric Markov-switching regression models and also generalized additive and generalized linear models. The feasibility of the suggested maximum penalized likelihood approach is demonstrated by simulation. We further illustrate the approach using two real data applications, modelling (i) how sales data depend on advertising spending and (ii) how energy price in Spain depends on the Euro/Dollar exchange rate.  相似文献   
943.
Based on paradigmatic claims of group dynamics as well as experiences in group dynamic training groups and discussions with students and trainers, in reflexive form we deal with the dialectic of direct and indirect communication and its influence on the identity formation of young people. We are concentrating on the connection between border-limiting globalisation, an identity search in the jungle of self-optimisation possibilities and the role of the virtual, indirect communication, when it is about to develop the greatest possible degree of affiliation in the greatest possible freedom and the desire for individuality which overexert the world wide web. We are not focussing that much on the characteristics of the generations “why” or “what” – this discussion can be critically connoted as well as being described as a hype – we are more interested in the historic, socio-political and economic background which control and influence our communication processes and therefore these developments, especially in the group dynamic context deserve increased attention.  相似文献   
944.
945.
Through an ethnographic study of ‘dirty work’ (refuse collection and street cleaning), this article explores how masculinity and class intersect — how, in a mutually constitutive sense, they produce attitudes and practices, strengths and vulnerabilities, which are shaped by shifting relations of privilege and power. We find resistance to class subordination through adherence to traditional forms of masculinity and through esteem‐enhancing social comparison (e.g., with women; with migrant workers). Men also mobilized powerful nostalgic themes around the loss of traditional jobs as well as trade union power. We argue that displays of masculine resilience in the face of devaluation are less indicative of a culture of masculine dominance but more an expression of vulnerability and social dislocation, serving both as a source of resistance whilst simultaneously reinforcing anchors of social disadvantage that characterize forms of dirty work. We suggest that combining social comparison with intersectionality can potentially highlight how categories of difference are strategically deployed in response to varied and unequally valued social positionalities.  相似文献   
946.
Utilizing country level data we demonstrate that a strong degree of investor protection can mitigate both asymmetric-information and agency problems that come along with R&D financing. Accordingly, we find that a higher degree of investor protection is associated with higher R&D investments. Moreover, for a sample of Austrian listed firms, we are able to show that ownership identities are significant drivers of R&D investments.  相似文献   
947.
This paper introduces a literature review of 83 studies dealing with the degree of adoption of lean manufacturing practices around the world, and the links between those practices and organisation performance. The results of this study revealed that lean practices application still occurs in a fragmented way, disregarding the systemic linkage that is essential to lean manufacturing. Forty-one articles have suggested a positive effect of lean practices in at least one operational, financial and/or environmental performance metric. Nevertheless, five studies indicated that some lean practices had a negative effect on operational or financial performance. High demand variability, a perceived result of long-term lean manufacturing implementation, a country/company’s organisational culture and the difficulty of traditional costing production systems to measure and compare investments and economic gains from adopting lean manufacturing over time are some of the reasons to explain that negative effect of lean practice on performance.  相似文献   
948.
Background Reliance on biomass for cooking and heating exposes many women and young children in developing countries to high levels of air pollution indoors. Environmental tobacco smoke also contributes to this indoor air pollution. This study estimates the effects of these sources of air pollution on acute respiratory infections (ARI) in children below 36 months of age in India.Methods The analysis is based on 29,768 children age 0–35 months included in India’s 1998–1999 National Family Health Survey (NFHS-2). Logistic regression is used to estimate effects.Results In NFHS-2, children living in households using only biomass fuels for cooking or heating are almost twice as likely to have suffered from ARI during the 2 weeks before interview as children in households using cleaner fuels (OR = 1.82; 95% CI: 1.58, 2.09). This effect is somewhat reduced when exposure to environmental tobacco smoke (ETS) and a number of other factors are statistically controlled (OR = 1.58; 95% CI: 1.28, 1.95). With these other variables controlled, children in households using a mix of biomass and cleaner fuels also have a higher risk of ARI than children in households using only cleaner fuels (OR = 1.41; 95% CI: 1.17, 1.70). With controls, the effect of biomass fuel use on ARI is stronger for boys (OR = 1.68; 95% CI: 1.26, 2.23) than for girls (OR = 1.49; 95% CI: 1.11, 2.01). The effect of ETS on ARI is also positive and significant, but smaller when other variables (including type of cooking fuel) are controlled (OR = 1.12; 95% CI: 1.01, 1.23). No modifying effects of cooking smoke and ETS are observed.Conclusions Findings support previous research showing positive effects of cooking smoke and ETS on ARI in young children. The relationship needs to be further investigated using more direct measures of smoke exposure and measures of outcome that are more specific to acute lower respiratory infections (ALRI), which are the most important component of overall ARI from a public health standpoint.Medical subject headings (MeSH) air pollution; indoor; biomass; smoke; environmental tobacco smoke; respiratory tract infections; child; India.Please address Correspondence to Vinod Mishra, DHR Division, ORC Macro, 11785 Beltsville Drive, Calverton, MD 20705, USA; e-mail: Vinod.Mishra@orcmacro.com  相似文献   
949.
Since monetary union between eastern and western Germany in 1990, non-employment spells have been shorter in the east, and there has been no convergence. Analysis of the German Socio-Economic Panel for 1990–2000 indicates that there is some convergence in the determinants of durations, owing to increasing age differentials for eastern men, and an increasing influence of children for eastern women. The latter has contributed to the decline in female employment. Skill affects non-employment duration less than it affects employment duration, and the gender gap in eastern non-employment duration cannot be characterized as a skills gap.I am very grateful to Ann Huff Stevens, Rachel Friedberg, Daniel Parent and Chris Sims for helpful discussions. I also thank participants in seminars at Boston College, Bristol, Essex, London School of Economics, University College London, and Warwick for comments on an earlier version. I am indebted to Yunning Xu for research assistance, and the Yale Center for International and Area Studies for financial support. I am also affiliated with the following institutes: NBER, CEPR, IZA, William Davidson, DIW, CIREQ and CIRANO. Responsible editor: Christoph M. Schmidt  相似文献   
950.
From 1999, all parents in Norway with children aged one to three, who did not attend publicly subsidised daycare, became eligible for a cash-for-care (CFC) subsidy. One effect of the CFC-subsidy was to increase in the relative price of external child care. This article analyses whether the CFC-subsidy has led to a reduction in the labour supply of mothers. A framework for evaluating policy reforms when reforms are equally and nation-wide accessible is put forward. The results show that the CFC-subsidy has reduced womens labour supply. The results are sustained after controlling for contemporaneous macroeconomic shocks, using a triple difference approach.The author thanks Hege Torp, Erling Barth and Harald Dale-Olsen at The Institute for Social Research, as well as participants at the European Society for Population Economics (ESPE) conference in Bilbao in June 2002, participants at the Lunch-seminar at Statistics Norway, and two anonymous referees for valuable comments. The work is financed by the Norwegian Research Council, grant #137230/530. The financial support is gratefully acknowledged.Responsible editor: Deborah Cobb-Clark.  相似文献   
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