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Robust Principal Component test in Gross Error Detection and Identification

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Journal of Shanghai Jiaotong university(Science) 2007年第5期12卷 553-558页

作者：高倩阎威武邵惠鹤 Dept.of Automation Shanghai Jiaotong Univ.

Principle component analysis （PCA） based chi-square test is more sensitive to subtle gross errors and has greater power to correctly detect gross errors than classical chi-square test. However, classical principal com- ponent test （PCT） is non-robust and can be very sensitive to one or more outliers. In this paper, a Huber function liked robust weight factor was added in the collective chi-square test to eliminate the influence of gross errors on the PCT. Meanwhile, robust chi-square test was applied to modified simultaneous estimation of gross error （MSEGE） strategy to detect and identify multiple gross errors. Simulation results show that the proposed robust test can reduce the possibility of type Ⅱ errors effectively. Adding robust chi-square test into MSEGE does not obviously improve the power of multiple gross error identification, the proposed approach considers the influence of outliers on hypothesis statistic test and is more reasonable.

关键词： gross error detection and identification chi-square test robust principle component analysis (PCA) modified simultaneous estimation of gross error (MSEGE)

GOODNESS-OF-FIT test WITH GENETIC BACKGROUND

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Journal of Systems Science & Complexity 2005年第1期18卷 27-34页

作者： WUJihua XIEMinyu PENGRong SUNZhihua DepartmentofMathematicsandStatistics CentralChinaNormalUniversityWuhan430079China

The chi-square test is a well-known goodness-of-fit test. It is available for arbitrary alternative hypothesis, particularly for a very general alternative. However, when the alternative is a “one-sided” hypothesis, which usually appears in genetic linkage analysis, the chi-square test does not use the information offered by the one-sided ***, it is possible that an appropriate one-sided test, which uses the information,will be better than the chi-square test. This paper gives such an efficient one-sided *** Carlo simulation results show that it is more powerful than the chi-square test, and its power has been increased by 30 percent as compared with that of the chi-square test in most situations.

关键词： chi-square test goodness-of-fit test monte carlo simulation

A Heuristic Sampling Method for Maintaining the Probability Distribution

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Journal of Computer Science & Technology 2021年第4期36卷 896-909页

作者： Jiao-Yun Yang Jun-Da Wang Yi-Fang Zhang Wen-Juan Cheng Lian Li Key Laboratory of Knowledge Engineering with Big Data of Ministry of Education Hefei University of Technology Hefei 230601China National Smart EldeTca/re International Science and Technology Coopemtion Base Hefei University of Technology Hefei 230601China School of Computer Science and Information Engirwering Hefei University of TechnologyHefei 230601China School of Mathematics Hefei University of TechnologyHefei 230601China

Sampling is a fundamental method for generating data *** many data analysis methods are developed based on probability distributions,maintaining distributions when sampling can help to ensure good data analysis ***,sampling a minimum subset while maintaining probability distributions is still a *** this paper,we decompose a joint probability distribution into a product of conditional probabilities based on Bayesian networks and use the chi-square test to formulate a sampling problem that requires that the sampled subset pass the distribution test to ensure the ***,a heuristic sampling algorithm is proposed to generate the required subset by designing two scoring functions:one based on the chi-square test and the other based on likelihood *** on four types of datasets with a size of 60000 show that when the significant difference level,a,is set to 0.05,the algorithm can exclude 99.9%,99.0%,93.1%and 96.7%of the samples based on their Bayesian networks-ASIA,ALARM,HEPAR2,and ANDES,*** subsets of the same size are sampled,the subset generated by our algorithm passes all the distribution tests and the average distribution difference is approximately 0.03;by contrast,the subsets generated by random sampling pass only 83.8%of the tests,and the average distribution difference is approximately 0.24.

关键词： Bayesian network chi-square test sampling probability distribution

Mathematical modeling of female breast cancer in Japan

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International Journal of Biomathematics 2020年第4期13卷 33-47页

作者： Ahmed Nagah Asmaa Amer Xinan Zhang School of Mathematics and Statistics Central China Normal UniversityWuhan 430079P.R.China Mathematics Department Faculty of Science Zagazig UniversityZagazigEgypt Mathematics Department Faculty of Science Menoufia UniversityEgypt

Cancer incidence rates are significantly diferent all over the *** cancer is affected by many factors,the most important being genetics and *** aim of this paper is to study the mutation mechanisms of breast cancer for Japanese women by fitting the incidence data of three high-quality population areas in Japan from 1985 to *** achieve this goal,we have set up multi-stage models within the mathematical model of Moolgavkar,Venzon,and *** models take both mutation rates and clonal expansion rates as parameters in each compartment into *** on our simulation outcomes,two to twelve driver mutations are sufficient in the pathway to female breast cancer in *** the other hand,a previous study demonstrated that breast cancer in American women requires two to fourteen gene mutations to get a cancerous ***,the 3-stage mat hematical model is the optimal model as it fits clinical data very nicely for all affected cases of females in Japan and the *** genetic instability has a promincnt effect on the tumorigenesis of Japanese females caused by the first four driver *** calculated results for Japanese women are compared with previous works for American women.

关键词： Breast cancer multi-stage models genetic instability chi-square test

Epidemiological Characteristics of Influenza A and B in Macao,2010–2018

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Virologica Sinica 2021年第5期36卷 1144-1153页

作者： HoiMan Ng Teng Zhang Guoliang Wang SiMeng Kan Guoyi Ma Zhe Li Chang Chen Dandan Wang MengIn Wong chioHang Wong Jinliang Ni Xiaohua Douglas Zhang Clinical Laboratory Kiang Wu HospitalMacao 999078Macao Faculty of Health Sciences University of MacaoMacao 999078Macao

Influenza is one of the major respiratory diseases in *** is a tourist city with high density of population and special population *** study on the epidemiological characteristics of influenza in Macao should bring great value for preventing influenza in tourist cities like Macao in the *** this study,we collected a total of 104,874 samples with influenza-like illness(ILI)in Macao from 2010 to ***-square test and binary multivariable logistic regression were used to investigate the epidemiological characteristics of influenza A and B in *** these ILI samples,the overall positive rate is 17.17%for influenza A and 6.97%for influenza *** epidemics of influenza in three years(i.e.,2012,2017 and 2018)differ from the remaining years(i.e.,normal years).In a normal year,influenza A occurs year-round whereas influenza B is *** research shows significant differences in influenza infections between different age groups in normal ***,our analysis shows no significant difference between locals and tourists in influenza A and B infection in a normal year,whereas the odds of influenza A in tourists were significantly higher than those in locals in July 2017 and the odds of influenza B in tourists were significantly higher than those in locals in January–February 2012 and January–February *** is possibly attributed by the policy of free vaccination to everyone in *** findings should be valuable for preventing influenza in not only Macao but also the world.

关键词： Influenza Epidemiology chi-square test Logistic regression Macao

Using Markov chains to predict the natural progression of diabetic retinopathy

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International Journal of Ophthalmology(English edition) 2015年第1期8卷 132-137页

作者： Priyanka Srikanth Jaslok Hospital & Research Centre

AIM: To study the natural progression of diabetic retinopathy in patients with type 2 ***: This was an observational study of 153 cases with type 2 diabetes from 2010 to 2013. The state of patient was noted at end of each year and transition matrices were developed to model movement between years. Patients who progressed to severe non-proliferative diabetic retinopathy(NPDR) were *** Chains and chi-square test were used for statistical ***: We modelled the transition of 153 patients from NPDR to blindness on an annual basis. At the end of year 3, we compared results from the Markov model versus actual data. The results from chi-square test confirmed that there was statistically no significant difference(P =0.70) which provided assurance that the model was robust to estimate mean sojourn times. The key finding was that a patient entering the system in mild NPDR state is expected to stay in that state for 5y followed by 1.07 y in moderate NPDR, be in the severe NPDR state for 1.33 y before moving into PDR for roughly8 y. It is therefore expected that such a patient entering the model in a state of mild NPDR will enter blindness after 15.29 ***: Patients stay for long time periods in mild NPDR before transitioning into moderate ***, they move rapidly from moderate NPDR to proliferative diabetic retinopathy(PDR) and stay in that state for long periods before transitioning into blindness.

关键词： diabetes mellitus diabetic retinopathy Markov Chains chi-square test transition probability matrix

Correlation knowledge extraction based on data mining for distribution network planning

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Global Energy Interconnection 2023年第4期6卷 485-492页

作者： Zhifang Zhu Zihan Lin Liping Chen Hong Dong Yanna Gao Xinyi Liang Jiahao Deng Guangzhou Power Supply Bureau of Guangdong Power Grid Co. Ltd.Guangzhou 510000P.R.China South china University of Technology School of Electric PowerGuangzhou 510000P.R.China

Traditional distribution network planning relies on the professional knowledge of planners,especially when analyzing the correlations between the problems existing in the network and the crucial influencing *** inherent laws reflected by the historical data of the distribution network are ignored,which affects the objectivity of the planning *** this study,to improve the efficiency and accuracy of distribution network planning,the characteristics of distribution network data were extracted using a data-mining technique,and correlation knowledge of existing problems in the network was obtained.A data-mining model based on correlation rules was *** inputs of the model were the electrical characteristic indices screened using the gray correlation *** Apriori algorithm was used to extract correlation knowledge from the operational data of the distribution network and obtain strong correlation *** of promotion and chi-square tests were used to verify the rationality of the strong correlation rules of the model *** this study,the correlation relationship between heavy load or overload problems of distribution network feeders in different regions and related characteristic indices was determined,and the confidence of the correlation rules was *** results can provide an effective basis for the formulation of a distribution network planning scheme.

关键词： Distribution network planning Data mining Apriori algorithm Gray correlation analysis chi-square test

Assessment of Hypertension-Induced Deaths in Ghana: A Nation-Wide Study from 2012 to 2016

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Journal of Data Analysis and Information Processing 2020年第3期8卷 158-170页

作者： David Adedia Livingstone Asem Simon Kojo Appiah Salifu Nanga Yeboah Boateng Kwabena O. Duedu Lotsi Anani Department of Basic Sciences School of Basic & Biomedical Sciences University of Health and Allied Sciences Ho Ghana Department of Epidemiology & Biostatistics School of Public Health University of Health and Allied Sciences Ho Ghana Department of Statistics and Actuarial Science College of Science Kwame Nkrumah University of Science and Technology Kumasi Ghana Department of Biomedical Sciences School of Basic and Biomedical Sciences University of Health and Allied Sciences Ho Ghana Department of Statistics and Actuarial Science College of Basic and Applied Sciences University of Ghana Legon Ghana

Globally, hypertension is one of the leading causes of death. It can potentially lead to heart disease and stroke, among others, that could result to premature death. In Ghana, hypertension is considered as a disease that contributes to an increase in outpatients’ attendance. To assess the trend differentials of hypertension-induced deaths in Ghana, chi-square test for equal proportions and Marascuilo procedure for pairwise comparison were performed using surveillance data on reported number of deaths from 2012 to 2016 across the then ten regions. The results show that incidence of hypertension-induced mortality was significantly different for almost all the regions and over the years. The incidence of hypertension-induced mortality has significantly reduced from 2012 to 2016. However, Volta Region recorded the highest incidence of mortality cases (p-value less of 0.0001) than the other regions during the period under review, while the Upper East Region recorded continuous increase in incidence of mortality cases with the highest in 2016. The Eastern Region, Central Region, and Greater Accra Region recorded significantly (p-value less of 0.0001) higher incidence of hypertension-induced mortality than the Ashanti Region, Brong Ahafo Region, Northern Region, Western Region and Upper West Region. The Upper West Region and Western Region had the lowest incidence of mortality. The decline in trend of hypertension-induced mortality could be attributed to some healthcare interventions put in place during the period. One of these interventions was the introduction of health insurance in 2003, a development which has been shown to affect the health seeking behaviors of the people. It is, therefore, important to investigate factors affecting these spatial and temporal dynamics in order to determine appropriate ways to actively control the hypertension-induced deaths in the country. Public education on health should be intensified so as to totally curb hypert

关键词： Hypertension Hypertension-Induced Mortality chi-square test Marascuilo test Incidence Rates Ghana

A Study on the Commonly Adopted Energy Sources and Production Systems for Domestic Hot Water in the Calabria Region (Italy)

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Journal of World Architecture 2021年第2期5卷 1-9页

作者： Marilena De Simone Liliangela Callea Gianmarco Fajilla Department of Environmental Engineering(DIAm) University of CalabriaP.Bucci87036Arcavacata di RendeItaly

Worldwide,there are many options to ensure domestic hot water(DHW)provision in *** study aimed to depict the distribution of energy sources and DHW production systems in the Calabria *** research was focused on understanding which variables,among contextual variables and building characteristics,may influence the adoption of a particular energy source or production *** statistics and chi-square test of independence have been *** relationships were found between the climatic zone and the energy source used as well as between the climatic zone and the production system installed in both households with a separated and a combined DHW production ***,the population of the municipality and the dwelling type resulted to be significant variables for the preference of an energy source or the diffusion of a combined production system.

关键词： DHW energy sources DHW production systems Survey chi-square test