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951.
With a new name for its professional organization (the American College of Physician Executives) and a new certifying organization (the American Board of Medical Management), the profession of medical management is in the throes of significant and far-reaching change. At the College's National Conference in Washington, D.C. in May, we talked to two leaders of the profession, Michael B. Guthrie, MD, MBA, FACPE, and Robert H. Hodge, Jr., MD, FACPE about what the future holds for physician executives and what physician executives can do to position themselves for success. Dr. Guthrie, the Immediate Past President of the College is Vice President for Business Development, Penrose/St. Francis Healthcare System, Colorado Springs, Colo. Dr. Hodge, the new President of the College, is a Program Director, W.K. Kellogg Foundation, Battle Creek, Mich. 相似文献
952.
W H Bruvold 《Journal of drug education》1990,20(2):139-152
Prominent nonquantitative reviews of research evaluating school-based interventions designed to deter adolescents from the use of tobacco, alcohol and other drugs found the methodology to be flawed and thus little evidence existed that the interventions had the desired impact. Recent meta-analytic reviews indicate that information-focused interventions have more impact upon knowledge but less upon attitudes and behavior whereas alternative interventions have less impact upon knowledge but more upon attitudes and behavior. This result is replicated by the current meta-analysis performed upon eight risk-reduction programs meeting six standard methodological requirements for evaluation research. 相似文献
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956.
A.H. Welsh 《Australian & New Zealand Journal of Statistics》2002,44(1):13-22
This paper considers the problem of undercount or incomplete detection in enumeration surveys that are intended to estimate population counts or population abundance. The problem is widespread in ecology but also occurs in other surveys: the census undercount is a well-known example of the problem. After framing the problem in a general context, the paper focuses on line transect sampling and the distance sampling method which has been widely applied in surveys of ecological populations. It describes distance sampling data and presents a graphical derivation of the distance sampling estimator. The graphical analysis leads to a new expression for the distance sampling estimator which gives useful insights into the nature of the estimator. The paper discusses the uniformity assumption on which distance sampling depends and describes the properties of the distance sampling estimator when uniformity does not hold. It then explores the relationship between this and other evaluations of distance sampling and mentions briefly some statistical ideas for treating the general incomplete detection problem. The paper concludes with some reflections on general insights arising from the research. 相似文献
957.
Michele Costa 《Statistical Methods and Applications》1994,3(1):25-36
Summary In this paper the factorial structure of some asset returns quoted at the Milan stock exchange is analyzed in order to detect
the presence of a dynamic component. The maximum likelihood estimates of the dynamic model, for which a space-state representation
and the Kalman filter were used, are compared with the estimates of the static model via the information criteria. There is
no evidence of dynamic factors underlying the analyzed samples of asset returns, while one static factor seems to be relevant.
Invited paper at the Conference held in Bologna, Italy, 27–28 May 1993, on ?Statistical Tests: Methodology and Econometric
Applications?. 相似文献
958.
The effects of non-normality on type-I and type-II errors in a one-way random model are investigated for moderate departures
from normality. It is found that the probabilities of both errors are more sensitive to the kurtosis of between group effects
than that of within group effects. 相似文献
959.
The number of households in the United States increased by over fifty percent in the 1960s and 1970s, nearly double the rate of population growth. Part of the increase is explained by the movement of large cohort groups of the population into prime household-forming age categories, but higher headship rates also contribute. Age-specific headship rate increases result from non-demographic factors, and this paper focuses on the role of government transfer payment programs. Specifically considered are Social Security, Aid to Families with Dependent Children, and Food Stamps. These programs are found to have accounted for as many as 4 million net household formations between 1961 and 1984. The findings have implications for expected households formations in the 1990s. 相似文献
960.
In this paper we analyse the average behaviour of the Bayes-optimal and Gibbs learning algorithms. We do this both for off-training-set error and conventional IID (independent identically distributed) error (for which test sets overlap with training sets). For the IID case we provide a major extension to one of the better known results. We also show that expected IID test set error is a non-increasing function of training set size for either algorithm. On the other hand, as we show, the expected off-training-set error for both learning algorithms can increase with training set size, for non-uniform sampling distributions. We characterize the relationship the sampling distribution must have with the prior for such an increase. We show in particular that for uniform sampling distributions and either algorithm, the expected off-training-set error is a non-increasing function of training set size. For uniform sampling distributions, we also characterize the priors for which the expected error of the Bayes-optimal algorithm stays constant. In addition we show that for the Bayes-optimal algorithm, expected off-training-set error can increase with training set size when the target function is fixed, but if and only if the expected error averaged over all targets decreases with training set size. Our results hold for arbitrary noise and arbitrary loss functions. 相似文献