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1.
One of the key features of Vietnamese family organization is patrilocality—the preference of married couples to coreside with the husband's parents. With data drawn from a retrospective survey of persons in 1,855 households in the largest province in the Red River Delta in northern Vietnam, we found that more than 75% of married respondents reported having lived with the grooms' family after marriage. The proportion of newly married couples that follow the patrilocal custom appears to have increased in recent decades, although the average duration of coresidence has declined. Some aspects of modernization, especially nonagricultural occupations and later age at marriage, contribute to a lower incidence of intergenerational coresidence, but the underlying cultural preference to live with the grooms' parents immediately after marriage appears to have become stronger in Vietnam. In contrast to some features of traditional family life that conflict with modernity, intergenerational coresidence can be quite functional in modernizing societies.  相似文献   
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The ensemble Kalman filter is an ABC algorithm   总被引:1,自引:0,他引:1  
The ensemble Kalman filter is the method of choice for many difficult high-dimensional filtering problems in meteorology, oceanography, hydrology and other fields. In this note we show that a common variant of the ensemble Kalman filter is an approximate Bayesian computation (ABC) algorithm. This is of interest for a number of reasons. First, the ensemble Kalman filter is an example of an ABC algorithm that predates the development of ABC algorithms. Second, the ensemble Kalman filter is used for very high-dimensional problems, whereas ABC methods are normally applied only in very low-dimensional problems. Third, recent state of the art extensions of the ensemble Kalman filter can also be understood within the ABC framework.  相似文献   
4.
This paper investigates ten Asian nations to consider how socio-economic values affect happiness and satisfaction. Moreover, it considers whether economic factors can strongly affect wellbeing under certain conditions. Males in Asia are said they have more opportunities to obtain higher happiness and satisfaction but it does not happen in the current study. Unemployment has negative and significant impact with regard to happiness and satisfaction in developing countries yet it does not have the same effect in developed nations. It is believed cultural value positively affects happiness and satisfaction in East Asia but the result in the models is different with no clear relationship between this variable and wellbeing. Furthermore, some people declare that a relative increase of income compared to the lowest group will lead them to lower life satisfaction.  相似文献   
5.
Single cohort stage‐frequency data are considered when assessing the stage reached by individuals through destructive sampling. For this type of data, when all hazard rates are assumed constant and equal, Laplace transform methods have been applied in the past to estimate the parameters in each stage‐duration distribution and the overall hazard rates. If hazard rates are not all equal, estimating stage‐duration parameters using Laplace transform methods becomes complex. In this paper, two new models are proposed to estimate stage‐dependent maturation parameters using Laplace transform methods where non‐trivial hazard rates apply. The first model encompasses hazard rates that are constant within each stage but vary between stages. The second model encompasses time‐dependent hazard rates within stages. Moreover, this paper introduces a method for estimating the hazard rate in each stage for the stage‐wise constant hazard rates model. This work presents methods that could be used in specific types of laboratory studies, but the main motivation is to explore the relationships between stage maturation parameters that, in future work, could be exploited in applying Bayesian approaches. The application of the methodology in each model is evaluated using simulated data in order to illustrate the structure of these models.  相似文献   
6.
One particular recurrent events data scenario involves patients experiencing events according to a common intensity rate, and then a treatment may be applied. The treatment might be effective for a limited amount of time, so that the intensity rate would be expected to change abruptly when the effect of the treatment wears out. In particular, we allow models for the intensity rate, post-treatment, to be at first decreasing and then change to increasing (and vice versa). Two estimators of the location of this change are proposed.  相似文献   
7.
Pham Dinh Tuan 《Statistics》2013,47(4):603-631
The paper is a survey of recent works on time series analysis using parametric models. The main emphasis is on linear models, in particular the ARMA model. Usual me¬thods of parameter estimation, goodness of fit tests and the choice of model order are con¬sidered. Some extensions of the methods to related problems are briefly discussed  相似文献   
8.
The joint models for longitudinal data and time-to-event data have recently received numerous attention in clinical and epidemiologic studies. Our interest is in modeling the relationship between event time outcomes and internal time-dependent covariates. In practice, the longitudinal responses often show non linear and fluctuated curves. Therefore, the main aim of this paper is to use penalized splines with a truncated polynomial basis to parameterize the non linear longitudinal process. Then, the linear mixed-effects model is applied to subject-specific curves and to control the smoothing. The association between the dropout process and longitudinal outcomes is modeled through a proportional hazard model. Two types of baseline risk functions are considered, namely a Gompertz distribution and a piecewise constant model. The resulting models are referred to as penalized spline joint models; an extension of the standard joint models. The expectation conditional maximization (ECM) algorithm is applied to estimate the parameters in the proposed models. To validate the proposed algorithm, extensive simulation studies were implemented followed by a case study. In summary, the penalized spline joint models provide a new approach for joint models that have improved the existing standard joint models.  相似文献   
9.

Sustainable landscaping programs are voluntary initiatives that recommend a set of practices to improve the environmental quality of urban ecosystems by providing landscaping materials, guidelines, and educational resources. Our goal was to examine the recommendations and outcomes of these programs in the United States and their value for encouraging conservation practices in residential ecosystems. We conducted a comprehensive web search and identified 193 sustainable landscaping programs in the United States. Programs aim to increase native species richness, affordably manage stormwater runoff, and offer residents meaningful experiences with nature. Sustainable landscaping programs present many opportunities to engage people with local ecological knowledge and conservation practices, provide accessible spaces for environmental education, cultivate interdisciplinary research collaborations, and advance inclusion in conservation. However, assessments of their ecological value are rare, leaving many questions surrounding the benefits to biodiversity and water quality afforded by participation. Many programs also require investments in landscaping materials and certification fees that might limit participation by some households. Future work should examine how recommended practices influence urban biodiversity, identify and address barriers to participation, and generate social-ecological knowledge that can inform future programs.

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Objective.?Methodological characteristics of the Aging Males’ Symptoms (AMS) scale point towards a high standard measurement and comparison of health-related quality of life (HRQoL) over time or intervention. However, the scale was neither developed nor standardized as a screening instrument for androgen deficiency.

Methods.?Data of the Austrian ANDROX study suggested to develop a composite screener for androgen deficiency based on AMS, age, and BMI, to determine sensitivity and specificity to detect low total testosterone (TT) levels. The findings were compared with those of an independent sample of urological patients with suspicion of androgen deficiency (AD) from Germany (n = 803).

Results.?A graphical solution for a composite-screening tool was proposed, with three levels of suspicion for AD: positive screening result (high suspicion), equivocal result, and negative screening result (no suspicion, AD unlikely). The percentage of TT values < 4 ng/ml were 18.7%, 40.7% and 58.8% in the three categories: negative, equivocal and positive, respectively. The findings were confirmed in the independent German sample. In both instances, neither sensitivity nor specificity was very high, i.e., between about 50% and 75%.

Conclusion.?The results of the development and initial validation of the new screener are promising. Further information, and experience from the practice, is needed to confirm or refute the hypothesis that this screener is a useful tool for medical practice.  相似文献   
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