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51.
Increasing medical technology, expertise and community expectations of health care are leading to an alarming escalation of health costs throughout the world. Many health planners are expressing doubts as to whether quality of health care can be maintained in the present circumstances. It is maintained that the Australian Government's proposal of National Health Insurance is an interim measure, intended to grant hospital and medical expenditure assistance to the entire community, at minimum cost. There is little evidence that the scheme threatens the medical market place, as it is seen at the moment, and a plea is made for productive and constructive discussion of the scheme by the medical profession.  相似文献   
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An intervention consisting of a thorough examination of the psychological worksite problems and a follow-up with feedback and recommendations was made in four different office worksites. One of the sites («active» group) was more organizational change-oriented than the others («passive» group). The course was followed before, three times during the 3 months of the intervention, and 4 months after the end of it, by means of three endocrine plasma markers: cortisol, prolactin and testosterone. In both study groups the prolactin levels increased in women during the starting phase of the intervention, whereas in men prolactin levels remained stable with a tendency (p=0.06) towards lowered prolactin levels during the end phase of the intervention in the active group. Cortisol levels increased markedly in the passive group and tended to decrease in the active group during the intervention (two-way interaction p=0.003), particularly in men. These findings may be indicative of feelings of uneasiness. Testosterone increased in the active group only, particularly at the beginning of the intervention and particularly in women, and also increased in a non-intervention control group. Testosterone levels are associated with anabolic activity. An increase may be indicative of a «placebo effect» of the intervention. Testosterone changes were still clearly observable after 4 months.  相似文献   
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Although much research on household work has focused on young dual-career couples, there has been speculation that retirement may have a significant effect on the arrangement of household activities in later life. Furthermore, involvement in the household is believed to influence psychological well-being. Available literature, however, provides contradictory evidence regarding the extent to which integration into household activities may either reduce or contribute to stress. The degree to which male involvement in the household in later life was stressful was examined in this research. Data were analyzed from structured interviews with 1165 older, married men who were employed full-time, part-time, or retired. Employed men were significantly less involved in the household than were the retired; however, men participated more in both masculine and feminine tasks if their wives were employed. Involvement in the household was not stressful although the benefits derived from participation varied somewhat by type of task.  相似文献   
56.
An internal pilot with interim analysis (IPIA) design combines interim power analysis (an internal pilot) with interim data analysis (two-stage group sequential). We provide IPIA methods for single df hypotheses within the Gaussian general linear model, including one and two group t tests. The design allows early stopping for efficacy and futility while also re-estimating sample size based on an interim variance estimate. Study planning in small samples requires the exact and computable forms reported here. The formulation gives fast and accurate calculations of power, Type I error rate, and expected sample size.  相似文献   
57.
An inverse Gaussian mixture of Poisson distributions(the P-IG distribution) is considered as a model for species abundance data,, Minimum chi-square and maximum likelihood methods of estimation for the zero-truncated P-IG distribution are developed, Ihe performance of the P-IG distribution is illustrated and discussed for several well-known sets of insect abundance data.  相似文献   
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A comparison between the two-sample t test and Satterthwaite's approximate F test is made, assuming the choice between these two tests is based on a preliminary test on the variances. Exact formulas for the sizes and powers of the tests are derived. Sizes and powers are then calculated and compared for several situations.  相似文献   
59.
Comment     
We propose a sequential test for predictive ability for recursively assessing whether some economic variables have explanatory content for another variable. In the forecasting literature it is common to assess predictive ability by using “one-shot” tests at each estimation period. We show that this practice leads to size distortions, selects overfitted models and provides spurious evidence of in-sample predictive ability, and may lower the forecast accuracy of the model selected by the test. The usefulness of the proposed test is shown in well-known empirical applications to the real-time predictive content of money for output and the selection between linear and nonlinear models.  相似文献   
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