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991.
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993.
The rising cost of health care threatens the very fabric of American society. With Americans widely practicing unhealthy life habits, such as using tobacco, eating imprudently and leading a sedentary lifestyle, they are at risk for health conditions that threaten to make them long-term liabilities to their employer. This article tells how one U.S. employer chooses to focus its workforce on wellness.  相似文献   
994.
995.
An algebraic theory of portfolio allocation   总被引:1,自引:0,他引:1  
Summary. Using group and majorization theory, we explore what can be established about allocation of funds among assets when asymmetries in the returns vector are carefully controlled. The key insight is that preferences over allocations can be partially ordered via majorized convex hulls that have been generated by a permutation group. Group transitivity suffices to ensure complete portfolio diversification. Point-wise stabilizer subgroups admit sectoral separability in fund allocations. We also bound the admissible allocation vector by a set of linear constraints the coefficients of which are determined by group operations on location and scale asymmetries in the rate of returns vector. For a distribution that is symmetric under a reflection group, the linear constraints may be further strengthened whenever there exists an hyperplane that separates convex sets. Received: May 15, 2001; revised version: March 20, 2002 RID="*" ID="*" Journal paper No. J-19797 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 3463, and supported by Hatch Act and State of Iowa funds. Correspondence to: D. A. Hennessy  相似文献   
996.
Prostate cancer     
Prostate cancer is the most common internal cancer in American males. There are many variables that effect prognosis, with the Gleason scoring system being one of the most important factors. There is controversy regarding the ideal treatment in various subsets of prostate cancer patients. Posttreatment prostate specific antigen values have prognostic significance.  相似文献   
997.
Several recent studies point to the value of using combinations of biochemical markers for the identification of alcohol abuse. The Early Detection of Alcohol Consumption (EDAC) test uses a statistical method that combines the results of several routine laboratory tests to form a metabolic fingerprint for each subject. In this study, we evaluated the use of the EDAC test as a screening tool to assess heavy drinking in insurance applicants. The EDAC was calculated by linear discriminate function analysis using the results of 14 routine tests including liver enzymes, lipids, proteins, and blood sugars. We collected and analyzed 1680 random samples at Heritage Laboratories (Olathe, Kan). Alcohol Detection Services (Brookfield, Wis) and Millennium Strategies (Madison, Wis) collaborated in the data analysis and interpretation of laboratory tests results. Ninety-three percent of applicants showed a negative EDAC test. The 7% (n = 134) who screened positive for the EDAC test were then reflexed to carbohydrate deficient transferin (CDT) and whole blood associated acetaldehyde (WBAA). Sixteen percent (22/134) showed a positive confirmatory test. Among these 16% of subjects, 41% (9/22) showed no elevations in liver enzymes or HDL-C results. Four of these subjects were among the top one third with the highest elevations for the CDT test in the entire group and one of them was positive for both the CDT and WBAA tests. These results suggest that the EDAC screen may provide an efficient alternative screening tool for the identification of heavy alcohol consumption not HBA as it identifies applicants with both normal or abnormal liver enzymes and HDL-C.  相似文献   
998.
999.
This paper investigates tax effects in the Canadian governmentbond market during the period 1964—1986. Unlike previousstudies, we apply both statistical and nonstatistical teststoanalyze clientele effects and market equilibria. The resultsdivide the sample into two distinct periods of time, with theend of 1976 marking the division. We find that tax effects arealmost nonexistent in the Canadian government bond market beforethe end of 1976, but are predominant in the post-1976 period.Non-segmented market equilibria cannot be rejected before 1977,but are strongly rejected after 1976. In fact, segmented equilibriawith clientele effects in both quantities and prices characterizethe entire five year period from 1982 to 1986. These findingsare consistent with tax reforms, government deficit financingand interest rate fluctuations in Canada during our sample period.  相似文献   
1000.
World-class supply management organizations like Honda of America, John Deere, Chrysler, Hewlett Packard, and Motorola all understand the power of continuous improvement in the supply base. The best supplier management and development programs help suppliers--on a long-term basis--develop their own strength and expertise in suggestion systems, new product development, and high quality production results.  相似文献   
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