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961.
Results from analysis of 227,771 discharge abstracts from 68 short-term, acute-care hospitals and from interviews with a stratified random selection of 24 of the 68 chief executives of these hospitals demonstrate that institutions perceive implementation of DRGs as fiscally constraining, especially in light of other resource-constraining conditions (an increase in unemployment resulting in fewer people with hospitalization insurance, in addition to severe cuts in Medicaid rolls and budget). Hospitals responded to DRGs by decreasing the use of affected resources or services available to the hospitalized Medicare patient. In order to survive a more economically stringent marketplace, hospitals no longer protected the traditional core within the Medicare inpatient market. They opted instead to change practices and products at the unregulated margins of the DRG system.  相似文献   
962.
It is widely believed that monetary aggregates have failed to predict economic performance over 1983-87. This paper observes that the traditional definition of money (M1 lessother checkable deposits, or M1A) shows no evidence of structural change, and yields lower prediction errors for both real GNP and inflation over 1983-87Q2 than the errors obtained using M1 or M2. If there is a mystery, it is not why MIA has done so well, but why economists abandoned it for M1 or what was once called M1B (currency, demand deposits, and other checkable deposits).  相似文献   
963.
964.
EBV has both physiological and psychological implications. Few medical/nursing interventions are available to alleviate the physical stressors and fatigue. The primary nursing intervention, therefore, becomes one of providing emotional support and psychosocial interventions. Providing measures to ensure adequate sleep will assist the patient in more positive feelings about self. Although causation and diagnosis of this syndrome may be debated in the medical literature, the nursing role is to provide support and guidance for these patients. Longitudinal studies could be done to facilitate the understanding of the long-term effects of EBV and the outcome measures of mental health interventions.  相似文献   
965.
966.
The college student-athlete: psychological considerations and interventions   总被引:1,自引:0,他引:1  
This article reviews the literature dealing with problems brought by student-athletes to college counseling and mental health centers. Among the issues discussed are fear of success; identity conflict; social isolation; poor athletic performance; academic problems; and career or vocational concerns. In addition, the authors examine the paradox that although athletes experience as much or more psychological distress as nonathletes, research indicates that athletes use professional services less often than nonathletes. Finally, the authors review approaches to psychological intervention, including short-term psychotherapy, very brief interventions, cognitive behavioral therapy, and career/vocational counseling, and discuss special considerations for conducting therapy with athletes.  相似文献   
967.
为了解决维修间隔期确定的难题,建立了维修间隔期和总停机时间之间关系的目标函数,以及时间延迟维修模型.根据故障记录数据和预防维修活动的检查数据,采用最大似然法估计有关缺陷发生率和时间延迟分布等参数.在所建立目标函数和估计参数的基础上,计算出最优的维修间隔期.  相似文献   
968.
Lehmann & Stein (1948) proved the existence of non-similar tests which can be more powerful than best similar tests. They used Student's problem of testing for a non-zero mean given a random sample from the normal distribution with unknown variance as an example. This raises the question: should we use a non-similar test instead of Student's t test? Questions like this can be answered by comparing the power of the test with the power envelope. This paper discusses the difficulties involved in computing power envelopes. It reports an empirical comparison of the power of the t test and the power envelope and finds that the two are almost identical especially for sample sizes greater than 20. These findings suggest that, as well as being uniformly most powerful (UMP) within the class of similar tests, Student's t test is approximately UMP within the class of all tests. For practical purposes it might also be regarded as UMP when moderate or large sample sizes are involved.  相似文献   
969.
This commentary discusses the articles in the special section, “Adolescent Career Development in Social Context.” Initially, common and integrative themes are identified and explicated based on the diverse perspectives of the work role in adolescence that were evident in these five articles. In addition, the theoretical frameworks provided by life-span, career development relational perspectives are discussed as possible means of integrating some of the findings presented by the authors of these articles. This article concludes with an observation on how the findings reported in the special section can inform career development scholarship and practice in the next millennium.  相似文献   
970.
This paper presents a limited assessment of the conservatism of the Accident Sequence Evaluation Program (ASEP) human reliability analysis (HRA) procedure described in NUREG/CR-4772. The data for this study are derived from simulator examination reports from the NRC requalification examination cycle for nuclear power plant operators. The ASEP procedure was used to estimate human error probability (HEP) values for critical tasks, and the HEP results were compared with the failure rates observed in the examinations. The ASEP procedure was applied by PNNL operator license examiners who supplemented the limited information in the examination reports with expert judgment based upon their extensive simulator examination experience. Comparison of the average of the ASEP HEP values with the fraction of the population actually failed and demonstrated that the ASEP HEP values are larger (conservative) by a statistically significant average factor of two. Partitioning of tasks into subgroups based on the ASEP HEP values and comparison of the subgroup average ASEP HEP values with observed subgroup failure rates showed little or no conservatism for small ASEP HEP values, but considerable conservatism for larger ASEP HEP values.  相似文献   
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