Estimating the Rayleigh distribution scale parameter from doubly censored samples—Some comments

In a recent paper in this journal, Lee, Kapadia and Brock (1980) developed maximum likelihood (ML) methods for estimating the scale parameter of the Rayleigh distribution from doubly censored samples. They reported convergence difficulties in attempting to solve numerically the nonlinear likelihood equation (LE). To mitigate these difficulties, they employed approximations to simplify the LE, but found that the solution of the resulting simplified equation can give rise to parameter estimates of erratic accuracy. We show that the use of approximations to simplify the LE is unnecessary. In fact, under suitable parametric transformation, the log-likelihood function is strictly concave, the ML estimate always exists, is unique and finite. Furthermore, the LE is easy to solve numerically. A numerical example is given to illustrate the computations involved.     

Benefits of preventive dentistry in children: Cost factors and public policy

Dental caries in children is now recognized as a preventable disease. The use of fluoride and sealants has produced a major reduction in caries prevalence among school aged children in the United States and other countries. A portion of the child population who are educationally and socioeconomically disadvantaged are not fully receiving these benefits. Public policy, insurance and medicaid groups must be made aware of these preventative measures and strategies developed to implement them.     

中学生常见不良性格及其矫治

当前 ,中学生常见的不良性格主要表现为偏执、怯懦、猜疑、狭隘、孤僻、抑郁等。这些不良性格的存在 ,将严重影响中学生的健康成长 ,必须采取有效的矫治措施 ,具体方法可采用积极的暗示调节法、自我安慰法、意识疗法、回归自然法、自得其乐法和自我检查法等     

MOVING OUT OF THE HOUSE: AN ANALYSIS OF CONGRESSIONAL QUITS

Despite extensive study concerning involuntary departures by U.S. House members, little has been said about voluntary departures from the House–-quit behavior. This paper has three primary purposes: (1) to establish a theoretical framework that models the full range of choices a representative faces in any given term, (2) to measure the impact of different variables that affect representatives' quit behavior, and (3) to explain why Republicans have been more likely to pursue higher office than their Democratic colleagues.     

教育旅游市场营销创新刍议

随着旅游需求个性化时代的到来,传统的把教育旅游等同于一般旅游的市场营销方式已经走到了尽头。因此,尽快实现教育旅游市场营销创新迫在眉睫。     

新形势下高校思想政治教育过程的行为分析

思想政治教育的过程是客体作用于主体，并通过主体不断内化的过程，其效果与教育者和被教育者的行为动机密切相关。本文以高校思想政治工作的教育者和被教育者为研究对象，通过分析他们在实施和接受思想教育过程中的行为动机，指出了当前思想政治教育工作在制度安排上存在的问题和不足，并初步提出了加强和改进思想政治工作的具体措施。     

浅析战略管理会计

20世纪80年代以来,全球性竞争日益激烈,世界经济环境日趋复杂,企业面临更多的机遇与挑战,战略管理会计也随之应运而生。战略管理会计是企业战略管理与管理会计相结合的产物。战略管理会计作为传统会计以及现在管理会计的延伸,在企业的生产经营中发挥着至关重要的作用。     

创新素质培养与课外创新活动

创新已经成为当今时代的标志和潮流 ,高校作为国家知识创新和技术创新体系的基础 ,加强对大学生的创新素质培养 ,是当前高校的战略任务和重要使命。从创新意识、创新思维、创新技能和创新人格四个方面阐述了创新素质培养的内涵 ,认为课外创新活动是创新素质培养的重要补充 ;同时提出了课外创新活动的模式 ,突出了创新意识、创新实践和创新成果之间的良性循环 ,构建了大学生课外创新活动的支撑体系。