http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Statistical inference of some effect sizes
ZHAOJUN,심성철,김형문 한국통계학회 2020 Journal of the Korean Statistical Society Vol.49 No.3
The reporting of effect sizes in social-scientific articles is becoming increasingly widespread and encouraged, particularly when research and experimental designs are involved. Two widely used experimental designs where the uniqueness of estimation can be guaranteed, the cell means and treatment effect models, are first introduced. Then, under those two experimental designs, it is proposed to explore the distributions of the effect sizes such as eta-squared ( 2 ), omega-squared ( 2 ) and Cohen’s f 2 . For each effect size in every experimental design, it is found that the distribution or transformation of distribution belongs to the non-central Beta family. Confidence intervals for effect size in the corresponding hypothesis are obtained by applying the results from the distributions combined with the probability limits. Based on the first two moments of distributions, which lead to the mean and standard deviation, a simulation study is given to help better understand the behaviour of 2 at different sample sizes and group numbers. This provides a reference for choosing sample and group sizes in experimental design. An application is reported for a psychological data set in order to illustrate how effect sizes perform in practice.
Modeling and damage detection for cracked I-shaped steel beams
Zhao, Jun,DeWoIf, John T. Techno-Press 2007 Structural Engineering and Mechanics, An Int'l Jou Vol.25 No.2
This paper presents the results of a study to show how the development of a crack alters the structural behavior of I-shaped steel beams and how this can be used to evaluate nondestructive evaluation techniques. The approach is based on changes in the dynamic behavior. An approximate finite element model for a cracked beam with I-shaped cross-section is developed based on a simplified fracture model. The model is then used to review different damage cases. Damage detection techniques are studied to determine their ability to identify the existence of the crack and to identify its location. The techniques studied are the coordinate modal assurance criterion, the modal flexibility, and the state and the slope arrays.
Analysis of Esophageal Cancer Time Trends in China, 1989-2008
Zhao, Jun,He, Yu-Tong,Zheng, Rong-Shou,Zhang, Si-Wei,Chen, Wan-Qing Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.9
National cancer incidence data were utilized to analyze trends in esophageal cancer incidence in China in order to provide basic information for making cancer control strategy. We retrieved and re-sorted valid esophageal cancer incidence data from National Central Cancer Registry Database over 20 years period from 1989 to 2008. Crude incidence and age-standardized incidence rates were calculated for analysis, with annual percent change estimated by Joinpoint software for long term trend analysis. The crude incidence rate of esophageal cancer was found to have remained relatively stable in both urban and rural areas over the 20 year period. Age standardized incidence rate (ASR) in cancer registration areas decreased from 39.5/100,000 in 1989 to 23.0/100,000 in 2008 in all areas (AAPC=-3.3%, 95% CI:-2.8~-3.7). The trend was no change in urban areas and 2.1% average annual decrease observed in rural aras. Before the year of 2000, esophageal cancer incidence rates significant decreased with 2.8% annually and then the rates kept stable. Over 20 years from 1989 to 2008, esophageal cancer age standardized incidence rate in cancer registration areas decreased with time. However, esophageal cancer is still a big issue and efforts for control should be continuously enhanced. Cancer registration is playing an important role in cancer control with the number of registries increasing and data quality improving in China.
Effects of a mild heat treatment on mouse testicular gene expression and sperm quality
Zhao, Jun,Zhang, Ying,Hao, Linlin,Wang, Jia,Zhang, Jiabao,Liu, Songcai,Ren, Bingzhong The Korean Society for Integrative Biology 2010 Animal cells and systems Vol.14 No.4
The decrease in sperm quality under heat stress causes a great loss in animal husbandry production. In order to reveal the mechanism underlying the sperm quality decrease caused by heat stress, we first established a mild heat-treated mouse model. Then, the sperm quality was identified. Further, the testicular proteome profile was mapped and compared with the control using 2D electrophoresis and mass spectrometry. Finally, the differential expressed proteins involved in the heat stress response were identified by real-time PCR and Western blotting. The results showed that heat stress caused a significant reduction in mouse sperm quality (P<0.05). Further, 52 protein spots on the 2D gel were found to differ between the heat-shocked tissues and the control. Of these spots, some repair proteins which might provide some explanation for the influence on sperm quality were found. We then focused on Bag-1, Hsp40, Hsp60 and Hsp70, which were found to be differently expressed after heat shock (P<0.05). Further analysis in this heat-shocked model suggests numerous potential mechanisms for heat shock-induced spermatogenic disorders.
Some counterexamples of a skew-normal distribution
Zhao, Jun,Lee, Sang Kyu,Kim, Hyoung-Moon The Korean Statistical Society 2019 Communications for statistical applications and me Vol.26 No.6
Counterexamples of a skew-normal distribution are developed to improve our understanding of this distribution. Two examples on bivariate non-skew-normal distribution owning marginal skew-normal distributions are first provided. Sum of dependent skew-normal and normal variables does not follow a skew-normal distribution. Continuous bivariate density with discontinuous marginal density also exists in skew-normal distribution. An example presents that the range of possible correlations for bivariate skew-normal distribution is constrained in a relatively small set. For unified skew-normal variables, an example about converging in law are discussed. Convergence in distribution is involved in two separate examples for skew-normal variables. The point estimation problem, which is not a counterexample, is provided because of its importance in understanding the skew-normal distribution. These materials are useful for undergraduate and/or graduate teaching courses.
Zhao, Jun,Kim, Hyoung-Moon The Korean Statistical Society 2016 Communications for statistical applications and me Vol.23 No.4
In this paper, we propose power t distribution based on t distribution. We also study the properties of and inferences for power t model in order to solve the problem of real data showing both skewness and heavy tails. The comparison of skew t and power t distributions is based on density plots, skewness and kurtosis. Note that, at the given degree of freedom, the kurtosis's range of the power t model surpasses that of the skew t model at all times. We draw inferences for two parameters of the power t distribution and four parameters of the location-scale extension of power t distribution via maximum likelihood. The Fisher information matrix derived is nonsingular on the whole parametric space; in addition we obtain the profile log-likelihood functions on two parameters. The response plots for different sample sizes provide strong evidence for the estimators' existence and unicity. An application of the power t distribution suggests that the model can be very useful for real data.
Research on Vehicle Type Recognition based on Datasurveying
Zhao jun,LIU Zejun 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.2
In the field of transportation, many of the vehicle amount of raw data value which can be accompanied by a large number of unknown information, and these information can provide people with more help. This paper aimed at the master data, and by using the method of survey of data modeling and prediction. First this paper introduces the data survey methods and the characteristics of the model, and then applied to the vehicles recognition judgment in their ability to recognize and to compare the analysis. The conclusion by principal component analysis and discriminant analysis method bus and van in four categories, the two on the training set and testing set of identification is quite high (high purity), so the four classified into two categories, the key to deal with opel (has been) and class and Po (saab) class. After the processing of raw data, and finally compares the model results.