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1.
Staggered nested experimental designs are the most popular class of unbalanced nested designs. Using a special notation which covers the particular structure of the staggered nested design, this paper systematically derives the canonical form for the arbitrary m-factors. Under the normality assumption for every random variable, a vector comprising m canonical variables from each experimental unit is normally independently and identically distributed. Every sum of squares used in the analysis of variance (ANOVA) can be expressed as the sum of squares of the corresponding canonical variables. Hence, general formulae for the expectations, variances and covariances of the mean squares are directly obtained from the canonical form. Applying the formulae, the explicit forms of the ANOVA estimators of the variance components and unbiased estimators of the ratios of the variance components are introduced in this paper. The formulae are easily applied to obtain the variances and covariances of any linear combinations of the mean squares, especially the ANOVA estimators of the variance components. These results are eff ectively applied for the standardization of measurement methods.  相似文献   
2.
Considering the integral relationship between public relations and democracy (Martinelli, 2011) coupled with the growing use of social media for democratic aims (Smith, 2011) the current study examines the effectiveness of Twitter as a public relations communications tool for congressional campaigns. Specifically, as a means of testing Twitter's effectiveness in informing and engaging voters, congressional candidate and political party Twitter use for all 435 U.S. House of Representatives races (N = 1284) are compared with 2010 election outcomes. Results indicate that candidates’ Twitter use significantly increased their odds of winning, controlling for incumbency and Party ID. Additionally, significant differences between incumbents’ and challengers’ Twitter use during the election cycle emerged, which has important implications for public relations practices aimed at achieving democratic outcomes.  相似文献   
3.
Introduction: It is well known that there is a reduction of circadian rhythm in blood testosterone levels with aging. Our previous report revealed that 3?mg of short-acting testosterone ointment (Glowmin: GL) elevated serum testosterone levels to within the physiological range for 4–6?h. The aim of this study was to clarify the clinical efficacy and safety of GL used topically once every morning, to enhance the circadian rhythm of testosterone, for late-onset hypogonadism (LOH).

Methods: A total of 61 LOH patients received 3?mg of GL topically once a day in the morning on scrotal skin for 24 weeks. The clinical efficacy of GL was evaluated by the aging males symptoms (AMS) scale, and blood sampling tests were measured before and after GL treatment.

Results: Mean patients age was 55.3?±?9.2 years old. Total AMS scores at 4, 12, and 24 weeks after GL treatments significantly decreased. The results of sub-analysis of AMS, including psychological, physical, and sexual factors also significantly improved after GL treatments. No severe adverse reactions or abnormal laboratory data were reported.

Conclusions: This study shows that TRT for LOH with once daily GL treatment supports testosterone circadian rhythm and should be considered to be an effective and safe therapy for LOH.  相似文献   
4.
日语中的汉字词多源于我国,其中大量汉字词词义与汉语相同,但也不乏词义相异之词。在教学中我们发现,正由于母语与日语中均存在同形词的“共同点”,导致学生往往“望文生义”,忽视部分词义相同或词义完全不同的同形词,造成误用和误译现象。本文就初级日语教学中经常出现的中日同形词误用及误译例,分析其在中日文不同语境中的用法,阐述在教学中排除母语干扰,转换思维,正确理解同形词对促进语言提高的重要性。  相似文献   
5.
Crossover designs have some advantages over standard clinical trial designs and they are often used in trials evaluating the efficacy of treatments for infertility. However, clinical trials of infertility treatments violate a fundamental condition of crossover designs, because women who become pregnant in the first treatment period are not treated in the second period. In previous research, to deal with this problem, some new designs, such as re‐randomization designs, and analysis methods including the logistic mixture model and the beta‐binomial mixture model were proposed. Although the performance of these designs and methods has previously been evaluated in large‐scale clinical trials with sample sizes of more than 1000 per group, the actual sample sizes of infertility treatment trials are usually around 100 per group. The most appropriate design and analysis for these moderate‐scale clinical trials are currently unclear. In this study, we conducted simulation studies to determine the appropriate design and analysis method of moderate‐scale clinical trials for irreversible endpoints by evaluating the statistical power and bias in the treatment effect estimates. The Mantel–Haenszel method had similar power and bias to the logistic mixture model. The crossover designs had the highest power and the smallest bias. We recommend using a combination of the crossover design and the Mantel–Haenszel method for two‐period, two‐treatment clinical trials with irreversible endpoints. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
6.
This paper deals with obtaining an upper tolerance limit for a largest observation X(n) in an ordered sample of size n from a continuous distribution where the first m observations X(1) < X(2) < … < X(m), l ≤ m < n, have been observed. A criterion of “goodness” of tolerance limit is developed, and a method is given to obtain the best tolerance limit. This method is applied to exponential and Pareto distributions.  相似文献   
7.
Reduced k‐means clustering is a method for clustering objects in a low‐dimensional subspace. The advantage of this method is that both clustering of objects and low‐dimensional subspace reflecting the cluster structure are simultaneously obtained. In this paper, the relationship between conventional k‐means clustering and reduced k‐means clustering is discussed. Conditions ensuring almost sure convergence of the estimator of reduced k‐means clustering as unboundedly increasing sample size have been presented. The results for a more general model considering conventional k‐means clustering and reduced k‐means clustering are provided in this paper. Moreover, a consistent selection of the numbers of clusters and dimensions is described.  相似文献   
8.
The purpose of this study was to evaluate the efficacy and safety of human chorionic gonadotropin (hCG) for patients with partial androgen deficiency of the aging male (PADAM). Twenty-one patients over 50 years of age with PADAM symptoms were included in this study. Laboratory and endocrinologic profiles were reviewed as appropriate, and PADAM symptoms were judged by means of several questionnaires such as the Aging Males' Symptoms (AMS) scale, short version of the International Index of Erectile Function (IIEF-5), and the Self-rating Depression Scale (SDS). Laboratory and endocrinologic values and symptom scores were evaluated and compared before and after treatment by hCG injection. The treatment period was 8.0 ± 5.0 months (3.0 – 24.0 months). Serum concentrations of testosterone, including total testosterone, calculated free testosterone, and calculated bioavailable testosterone, increased significantly. AMS total scores and subscores decreased significantly after treatment. However, IIEF-5 and SDS scores did not improve. With respect to adverse effects, laboratory tests showed that only red blood cell count, hematocrit and hemoglobin level increased significantly after treatment, however, these values remained within the normal range. No adverse effect was identified after treatment. We conclude that hCG injection may be considered as a treatment for PADAM.  相似文献   
9.
We experimentally found a negative effect of subsequent group conversations after media exposure on the audience's attitudes toward the covered organization, while we found sided media exposure to predict both attitudes and behavioral intentions relevant to the covered organization. The extent of conversational engagement immediately following media exposure also helped predict future word-of-mouth (WOM) intentions. These results highlight the roles of interpersonal interactions after media exposure to explain and predict public relations outcomes.  相似文献   
10.
An expansion formula for the coverage probability of prediction region based on a shrinkage estimator proposed by Joshi [Joshi, V. M. (1967). Inadmissibility of the usual confidence sets for the mean of a multivariate normal population. Ann. Math. Statist., 38, 1868–1875.] is obtained. Its error bound is evaluated in terms of a function of an unknown parameter. Applying this result, three types of asymptotic expansions are derived. These expansions show inadmissibility of the usual prediction region.  相似文献   
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