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841.
Certain recurrence relations for the moments of different orders of the largest order statistic from a gamma distribution with shape parameter p are obtained. By using this it is shown that for obtaining the moment of any order of each order statistic of a sample of size n from the gamma distribution, one has to evaluate at most n-2 single integrals. 相似文献
842.
Michael L. Hughes D.M.D. Donald W. Legler D.D.S. Ph.D. 《Journal of American college health : J of ACH》2013,61(6):293-296
Abstract The Student Dental Health Program (SDHP) is an open panel, prepaid dental insurance plan at the University of Alabama in Birmingham. The program was developed primarily to provide optimal dental health service; however the SDHP also serves educational and research functions that are consistent with the objectives of the university. The student bodies of the Schools of Dentistry, Medicine, Nursing, and Optometry constitute the enrollee population. Total cost rose from $18,418 in 1969–70 with 862 enrollees, to $70,930 in 1975–76 with 1,618 enrollees. During the same period the number of procedures completed increased from 2,868 to 6,796, with the average cost per procedure increasing from $6.42 to $10.44. The number of restorative services declined and preventive services increased. In 1976–77 benefits per student treated were estimated at $80 as compared to the annual fee of $48. The value of unmet needs upon entrance to the program averaged $59 per enrollee in 1974–75. By 1976–77 this figure was reduced to $26 due to implementation of an initial screening. The program is self-supporting due to a variety of cost containment measures. On balance, the program can be considered successful and beneficial to all parties concerned. 相似文献
843.
Lynne Baillie PhD Doris Callaghan MSc Michelle L. Smith MSc 《Journal of American college health : J of ACH》2013,61(4):260-265
Abstract Background: Young adults remain the earliest legal target for the tobacco industry. Against this, the existence of smoking policies would appear to offer some protection to students on campus. However, little research has been conducted into the outcomes of such policies from a student perspective. Methods: The authors conducted 8 focus groups at 4 selected Canadian undergraduate campuses to investigate student perceptions and behaviors resulting from campus smoking policies. Results: Results indicated that student smoking behaviors are minimally impacted by campus smoking policies due to seriously compromised implementation and enforcement. Conclusions: These findings imply that the presence of campus smoking policies and claims of “smoke-free” campuses should not be misinterpreted as achievement and without renewed focus and adequate tobacco control infrastructure, it will remain possible for young adults to initiate and maintain tobacco smoking on campus. 相似文献
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848.
Lawrence S. Evans 《The American statistician》2013,67(2):79-81
Periodically, the pyramid or “chain letter” scheme is offered to Americans under the guise of a business dealership. Recently, the FTC ordered Glen Turner's “Dare to be Great” firm to repay 44 million dollars to participants. In order to demonstrate that the potential gains are misrepresented by promoters, a probability model of the pyramid scheme is developed. The major implications are that the vast majority of participants have less than a ten percent chance of recouping their initial investment when a small profit is achieved as soon as they recruit three people and that, on the average, half of the participants will recruit no one else and lose all their money. 相似文献
849.
M. L. Walker Y. H. Dovoedo S. Chakraborti C. W. Hilton 《The American statistician》2013,67(4):348-353
The boxplot is an effective data-visualization tool useful in diverse applications and disciplines. Although more sophisticated graphical methods exist, the boxplot remains relevant due to its simplicity, interpretability, and usefulness, even in the age of big data. This article highlights the origins and developments of the boxplot that is now widely viewed as an industry standard as well as its inherent limitations when dealing with data from skewed distributions, particularly when detecting outliers. The proposed Ratio-Skewed boxplot is shown to be practical and suitable for outlier labeling across several parametric distributions. 相似文献
850.
S. Kalke 《Journal of Statistical Computation and Simulation》2013,83(4):641-667
In this paper, we introduce the p-generalized polar methods for the simulation of the p-generalized Gaussian distribution. On the basis of geometric measure representations, the well-known Box–Muller method and the Marsaglia–Bray rejecting polar method for the simulation of the Gaussian distribution are generalized to simulate the p-generalized Gaussian distribution, which fits much more flexibly to data than the Gaussian distribution and has already been applied in various fields of modern sciences. To prove the correctness of the p-generalized polar methods, we give stochastic representations, and to demonstrate their adequacy, we perform a comparison of six simulation techniques w.r.t. the goodness of fit and the complexity. The competing methods include adapted general methods and another special method. Furthermore, we prove stochastic representations for all the adapted methods. 相似文献