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Heritabilities and genetic correlations for body size characters and development period in a coccinellid beetle,Harmonia axyridis were estimated by a sib-analysis experiment. Positive genetic correlations were detected between size characters and development rate. If this is upheld in the field, genetic variation would be eliminated, as the loci affecting the characters are supposed to be fixed. However, the results indicated moderate heritabilities for all characters. Possible explanations for the results are discussed.  相似文献   
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In this work, we propose a consistent method of estimation for the parameters of the three-parameter lognormal distribution. We then discuss some properties of these estimators and show by means of a Monte Carlo simulation study that the proposed estimators perform better than some other prominent estimators in terms of bias and root mean squared error. Finally, we present two real-life examples to illustrate the method of estimation proposed.  相似文献   
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In this paper, we propose a consistent method of estimation for the parameters of the three-parameter inverse Gaussian distribution. We then discuss some properties of these estimators and show by means of a Monte Carlo simulation study that the proposed estimators perform better than some other prominent estimators in terms of bias and root mean squared error. Finally, we present two real-life examples to illustrate the method of inference developed here.  相似文献   
5.
Many clinical research studies evaluate a time‐to‐event outcome, illustrate survival functions, and conventionally report estimated hazard ratios to express the magnitude of the treatment effect when comparing between groups. However, it may not be straightforward to interpret the hazard ratio clinically and statistically when the proportional hazards assumption is invalid. In some recent papers published in clinical journals, the use of restricted mean survival time (RMST) or τ ‐year mean survival time is discussed as one of the alternative summary measures for the time‐to‐event outcome. The RMST is defined as the expected value of time to event limited to a specific time point corresponding to the area under the survival curve up to the specific time point. This article summarizes the necessary information to conduct statistical analysis using the RMST, including the definition and statistical properties of the RMST, adjusted analysis methods, sample size calculation, information fraction for the RMST difference, and clinical and statistical meaning and interpretation. Additionally, we discuss how to set the specific time point to define the RMST from two main points of view. We also provide developed SAS codes to determine the sample size required to detect an expected RMST difference with appropriate power and reconstruct individual survival data to estimate an RMST reference value from a reported survival curve.  相似文献   
6.
在伪满洲国的文学研究中,即使有关于个别作家及作品的论述,把历史小说作为一个种类进行论述并不多见.但是在拥有悠久历史文化积蓄的中国,以这种丰富的历史典故为题材的文学作品对于五四以后的新文学也是有力的表现方法.尤其是在严厉的言论统治、不能自由表达的伪满洲国,是有效的欺骗敌人的表达手段.作家们以历史上有名人物及故事为题材,描写异民族支配下的中国人民的苦恼及悲哀.在伪满洲国,历史小说是值得重视的文学题材.  相似文献   
7.
Lognormal distribution is one of the popular distributions used for modelling positively skewed data, especially those encountered in economic and financial data. In this paper, we propose an efficient method for the estimation of parameters and quantiles of the three-parameter lognormal distribution, which avoids the problem of unbounded likelihood, by using statistics that are invariant to unknown location. Through a Monte Carlo simulation study, we then show that the proposed method performs well compared to other prominent methods in terms of both bias and mean-squared error. Finally, we present two illustrative examples.  相似文献   
8.
In this article the author examines the four features found in the emerging Japanese multinational enterprises, (1) joint ventures with participation of trading companies, (2) the R & D capabilities, (3) the Japanese style of management, and (4) socio-political reactions in Asian countries. These features provide the Japanese multinational enterprises with both opportunities and challenges for their future development. Proper consideration is given to the comparison with the American multinational enterprises.  相似文献   
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In this paper, we develop a model characterized by skill-biased technological change and increasing costs of education to investigate income inequality. Irregular workers cannot escape poverty by commencing investment in education because wage inequality between regular and irregular workers widens and the price of education increases with the average level of education. Moreover, if the productivity of elementary education is low relative to that of higher education, middle-income individuals are eventually unable to pursue higher education because the threshold for education expenditure rises with the price of education. Thus, income inequality may widen, even among regular workers.  相似文献   
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