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81.
In the lifetime experiments, the joint censoring scheme is useful for planning comparative purposes of two identical products manufactured coming from different lines. In this article, we will confine ourselves to the data obtained by conducting a joint progressive Type II censoring scheme on the basis of the two combined samples selected from the two lines. Moreover, it is supposed that the distributions of lifetimes of the two products satisfy in a proportional hazard model. A general form for the distributions is considered, and we tackle the problem of obtaining Bayes estimates under the squared error and linear-exponential (LINEX) loss functions. As a special case, the Weibull distribution is discussed in more detail. Finally, the estimated risks of the various estimators obtained are compared using the Monte Carlo method.  相似文献   
82.
Stein’s (1945) two sample approach and Tukey’s T-Method of multiple comparisons (see e.g. Miller, 1966, Ch. 2) are combined to obtain fixed width simultaneous confidence intervals and simultaneous test procedures of predetermined Type I and Type II error levels, for all contrasts, in a one way layout. The necessary constants for implementing the two stage procedure are obtained under a least favorable configuration of the parameters. This provides the required protection of the null and alternative hypotheses under any configuration of parameters. A table is provided for some selected designs and error levels and an example is given to illustrate certain features of the new procedure.  相似文献   
83.
Log-location-scale distributions are widely used parametric models that have fundamental importance in both parametric and semiparametric frameworks. The likelihood equations based on a Type II censored sample from location-scale distributions do not provide explicit solutions for the para-meters. Statistical software is widely available and is based on iterative methods (such as, Newton Raphson Algorithm, EM algorithm etc.), which require starting values near the global maximum. There are also many situations that the specialized software does not handle. This paper provides a method for determining explicit estimators for the location and scale parameters by approximating the likelihood function, where the method does not require any starting values. The performance of the proposed approximate method for the Weibull distribution and Log-Logistic distributions is compared with those based on iterative methods through the use of simulation studies for a wide range of sample size and Type II censoring schemes. Here we also examine the probability coverages of the pivotal quantities based on asymptotic normality. In addition, two examples are given.  相似文献   
84.
In this paper we consider the issue of constructing retrospective T 2 control chart limits so as to control the overall probability of a false alarm at a specified value. We describe an exact method for constructing the control limits for retrospective examination. We then consider Bonferroni-adjustments to Alt's control limit and to the standard x 2 control limit as alternatives to the exact limit since it is computationally cumbersome to find the exact limit. We present the results of some simulation experiments that are carried out to compare the performance of these control limits. The results indicate that the Bonferroni-adjusted Alt's control limit performs better that the Bonferroni-adjusted x 2 control limit. Furthermore, it appears that the Bonferroni-adjusted Alt's control limit is more than adequate for controlling the overall false alarm probability at a specified value.  相似文献   
85.
The problem of testing the equality of the noncentrality parameters of two noncentral t-distributions with identical degrees of freedom is considered, which arises from the comparison of two signal-to-noise ratios for simple linear regression models. A test procedure is derived that is guaranteed to maintain Type I error while having only minimal amounts of conservativeness, and comparisons are made with several other approaches to this problem based on variance stabilizing transformations. The new procedure derived in this article is shown to have good properties and will be useful for practitioners.  相似文献   
86.
Supporting healthy lifestyle behaviours is a key aspect of preventing type 2 diabetes which disproportionately affects disadvantaged groups from a younger age. Formative participatory research was undertaken to design a program for young Aboriginal people in a remote town in North West Australia with a high level of health needs and relatively few prevention initiatives. Focus groups and advisory discussions with Aboriginal community members were used to determine the nature of the program. The need for a comprehensive program was consistently expressed and limited healthy lifestyle knowledge and difficulties with healthy eating influenced by food environments were noted to be important. With guidance from the Derby Aboriginal Health Service, findings were integrated with previous international research evidence to develop a program tailored to local Aboriginal people aged 15–25 years and refine it after piloting. This 8-session program, ‘Maboo wirriya, be healthy’ involved an education component consistent with the US Diabetes Prevention Program and practical activities including group exercise. Changes to program structure and documentation were made after piloting for future use. The community-directed approach used in this study is vital to ensure relevance of localised chronic disease prevention programs in a range of settings.  相似文献   
87.
Despite a long history within the field of leadership, the subject of authoritarianism and how it influences leadership and leadership processes has been neglected in recent decades. However, recent global events make it clear that a better understanding of authoritarianism is needed and that leadership researchers would benefit from a renewed interest in studying why followers embrace autocratic leaders. The nature of authoritarian character, how authoritarian values develop, and how it is measured will be discussed. We will also review autocratic leadership, the factors that make it more likely, its consequences for followers, and the moderators of its effects. A future research agenda for the study of authoritarian character and autocratic leadership will be provided.  相似文献   
88.
本文对传统的石油地质理论定义的含油气面积提出了异议,用倒转背斜油气藏、断层下盘油气藏和不整合面下油气藏的实例阐明在传统定义下确定含油气面积存在的问题,指出用这种方法确定的含油气面积小于实际面积。笔者将含油气面积定义为含油气体在水平面上的投影区域,并推荐了三种正确的确定方法、  相似文献   
89.
Background: The prevalence rates for both sarcopenia and erectile dysfunction (ED) gradually increase in middle-aged and elderly diabetic male population and they impair physical functioning, sexual functioning, and quality of life. The aim of the present study was to evaluate the sarcopenia in patients with diabetic ED.

Methods: The study included 98 male patients with type II diabetes mellitus (DM) aged 18–80?years. Blood chemistry and hormone levels were obtained. The International Index of Erectile Function (IIEF-5) questionnaire was administered to the patients. The patients were divided into three groups according to the IIEF-5 score; a score of 5–10 points indicated severe ED, a score of 11–20 indicated moderate ED, and a score of 21–25 points indicated no ED. The muscle mass, handgrip strength, timed up and go test, upper mid-arm circumference, calf circumference, and body mass index were obtained. The statistical analysis was performed using MedCalc Statistical Software version 12.7.7. All parameters were compared between the three groups.

Results: Of 98 patients included in the study, 84 patients had severe sarcopenia, 13 had moderate sarcopenia, while only one patient had normal muscle mass. The mean age was 56.59?±?11.46?years. When patients were divided into three groups according to IIEF-5 score, 38 had severe ED, 39 had moderate ED, and 21 had no ED. There was a significant difference between the three groups in terms of handgrip strength, timed up and go test scores, upper mid-arm circumference, and calf circumference (p?Conclusions: Although muscle mass remains unchanged, muscle strength and physical performance decrease in diabetic ED patients. Diabetic patients with severe and moderate ED have lower muscle strength and physical performance.  相似文献   
90.
政治心理学起源于对政治现象中政治人的精神与生理的关注,故此,对于政治人格的精神病理学研究一直是这门学科的主题。然而,人格一词对于政治学家和心理学家而言范围大小不同,心理学家将人格作为解释个体在面临不同刺激时的行为反应模式,政治学家更倾向于将人格看作一种心理防卫机制,进而探讨这种机制对于政治行为产生的影响。从概念界定到研究方法等方面,精神分析既促进了人格研究的深化和成型,又给政治—人格分析法带来了挑战。  相似文献   
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