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41.
首先分析了对数最小二乘排序法的特点,说明它是一种值得重视的好方法;并进一步阐述了这一方法的基本原理,着重地对群体判断下求加权的综合排序向量的方法进行了严密的数学推导;提出了在加权的综合排序中权重系数确定的新見解,并举例子以解释。 相似文献
42.
D R Lairson R Harrist D W Martin R Ramby T A Rustin J M Swint K Harlow J Cobb 《Journal of drug education》1992,22(4):337-352
Primary care physicians are well situated to identify patients with substance abuse problems and motivate them to seek appropriate assistance, but active programs are the exception. A study in a community setting was undertaken to assess the CAGE (the first letters of key words in a series of four questions about drinking: cut down; annoyed; guilty; and eye-opener), instrument in the routine screening for alcohol problems in both new and established patients. The screening process identified subjects for a pilot evaluation of a motivational interview designed to encourage problem-solving behavior. This article focuses on the screening results and the use of the CAGE instrument. During June and July of 1990, 687 patients of two primary care physicians belonging to a large group practice were asked to complete a health questionnaire that included the CAGE. Those who responded affirmatively to at least two of the four CAGE questions were requested to participate in follow-up assessment of problems associated with alcohol and health. The type and severity of alcohol problems experienced by patients who scored positive on the CAGE are described. Prevalence of a positive score on the CAGE was 8.6 percent with males, smokers, and blue collar and unemployed persons being more likely to score positive. The positive predictive value was .68. Primarily, persons with moderate alcohol problems were identified. Results show that the CAGE instrument is a useful screening device for identifying those with mild to moderate substance abuse problems, increasing the opportunity for intervention prior to serious medical complications. The instrument is easily administered, and has demonstrated relatively high levels of sensitivity and specificity. When combined with assessment and motivational interviews, the CAGE shows promise in the secondary prevention of substance abuse and related health problems. 相似文献
43.
WILLIMACK DIANE K.; SCHUMAN HOWARD; PENNELL BETH-ELLEN; LEPKOWSKI JAMES M. 《Public opinion quarterly》1995,59(1):78-92
We conducted a randomized experiment on a face-to-face interviewsurvey in order to test the effects on response rates of a prepaidnonmonetary incentive. Results showed a statistically significantincrease in response rates, mostly through reduction in refusalrates, in the half sample that received the incentive (a gift-typeballpoint pen) as compared with a no incentive control group.The effect appears to be due to greater cooperation from incentiverecipients at the initial visit by an interviewer. Unexpectedly,the incentive group also showed a significantly higher rateof sample ineligibility, possibly due to easier identificationof vacant residences or nonexistent addresses. In addition,evidence suggests greater response completeness among respondingincentive recipients early in the interview, with no evidenceof increased measurement error due to the incentive. 相似文献
44.
The robustness of Mauchly's sphericity test criterion when sampling from a mixture of two multivariate normal distributions is studied. The distribution of the sphericity test criterion when the sample covariance matrix has a non-central Wishart density of rank one is derived in terms of Meijer's G-functions; its distribution under the mixture model is then deduced. The robustness is studied by computing actual significance levels of the test under the mixture model using the critical values under the usual normal model. 相似文献
45.
Collective bargaining requires that an agent represent workers. This paper examines the implications for the trade union movement
of the resulting agency costs. Without transferable rights in the union, union members lack the means and incentive to bring
forth the innovative agent controls common to the modern corporation. Considerations of the bargaining strengths of employers
and employees, each represented by an agent, provide an explanation of the simultaneous decline of private sector union membership
(corporate share holders have been more successful at lowering agency costs) and growth of public sector union representation
(where the union official, a “double agent,” serves the interest of both employee and bureaucratic employer).
The authors acknowledge the helpful remarks Donald L. Martin whose earlier research on property rights in unions inspired
this effort. Don Bellante’s work was supported by a grant from the Research Committee of the College of Business Administration,
University of South Florida. 相似文献
46.
The problem of estimating the value of an x variable for a given proportion of an observed value of the y variable is consdered for a non-linear model. Asymptotic confidence limits are obtained and an application of the method is illustrated witreal data. 相似文献
47.
We propose some estimators of noncentrality parameters which improve upon usual unbiased estimators under quadratic loss. The distributions we consider are the noncentral chi-square and the noncentral F. However, we give more general results for the family of elliptically contoured distributions and propose a robust dominating estimator. 相似文献
48.
刘坚 《苏州科技学院学报(社会科学版)》1992,(Z2)
本文利用EHT(Extended Huckel Method)紧束缚能带计算方法,计算了Tl_2Ba_2CaCu_2O_8在晶体中三种不同氧缺位条件下的电子能带,讨论了晶体中不同氧缺位对该超导体的能带结构,体系总能量,总态密度和Cu—O面上Cu和O的电荷分布的影响,指出这三种氧缺位结构都有可能存在于该超导体中,并且对超导电性的贡献是相同的。 相似文献
49.
刘力 《兰州大学学报(社会科学版)》1996,(1)
本文探讨了世界贸易组织的优势和面临的挑战,并对其发展前景作了展望。作者认为,与过去的国际贸易组织和关贸总协定相比,世界贸易组织具有许多优势,世界经济联系越来越紧密、冷战后各国对经济安全的重视、世界经济多极化的发展、发展中国家贸易政策的自由化和自身较完善的机制等都是其优势所在。但同时世界贸易组织也面临着各国经济摩擦加剧、发达国家贸易保护主义抬头、区域经济集团剧增和自身机制尚存在缺陷等挑战。基于以上分析,作者对世界贸易组织的未来前景持谨慎的乐观态度,认为世界贸易组织不会象国际贸易组织那样中途夭折,也不会象关贸总协定那样软弱被动,它将在成员国之间不断的冲突与妥协中存在并发挥比较强有力的作用。 相似文献
50.
本文利用实验中得到的电动势随时间变化的E~t图,研究了α—酮戊二酸(以α—Ke表示)—KBrO_3—H_2SO_4—丙酮(以Act表示)体系的Mn~(2+)催化下的振荡反应及许多因素对振荡反应的影响,根据实验结果及振荡反应的一般机理,探讨了该体系的振荡机理,归纳出振荡反应参数与反应物浓度之间存在的关系式,并对实验现象作了定性的说明。 相似文献