• Title/Summary/Keyword: inferential statistical analysis

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An Evaluation of the Use of Statistical Methods in the Journal of Tuberculosis and Respiratory Diseases ([결핵 및 호흡기질환] 게재 논문의 통계적 기법 활용에 대한 평가)

  • Koh, Won-Jung;Lee, Seung-Joon;Kang, Min Jong;Lee, Hun Jae
    • Tuberculosis and Respiratory Diseases
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    • v.57 no.2
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    • pp.168-179
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    • 2004
  • Background : The statistical analysis is an essential procedure ensuring that the results of researches are based on evidences rather than opinion. The purpose of this study is to evaluate which statistical techniques are used and whether these statistical methods are used appropriately or not in the journal of Tuberculosis and Respiratory Diseases. Materials and Methods : We reviewed 185 articles reported in the journal of Tuberculosis and Respiratory Diseases in 1999. We evaluated the validity of used statistical methods based upon the checklist that was developed on the basis of the guideline for statistical reporting in articles for medical journals by International Committee of Medical Journal Editors. Results : Among 185 articles, original articles and case reports were 110 (59.5%) and 61 (33.0%) respectively. In 112 articles excluding case reports and reviews, statistical techniques were used in 107 articles (95.5%). In 94 articles (83.9%) descriptive and inferential methods were used, while in 13 (11.6%) articles only descriptive methods were used. With the types of inferential statistical techniques, comparison of means was most commonly used (64/94, 68.1%), followed by contingency table (43/94, 45.7%) and correlation or regression (18/94, 19.1%). Among the articles in which descriptive methods were used, 83.2% (89/107) showed inappropriate central tendency and dispersion. In the articles in which inferential methods were used, improper methods were applied in 88.8% (79/89) and the most frequent misuse of statistical methods was inappropriate use of parametric methods (35/89, 39.3%). Only 14 articles (13.1%) were satisfactory in utilization of statistical methodology. Conclusion : Most of the statistical errors found in the journal were misuses of statistical methods related to basic statistics. This study suggests that researchers should be more careful when they describe and apply statistical methods and more extensive statistical refereeing system would be needed.

Bivariate odd-log-logistic-Weibull regression model for oral health-related quality of life

  • Cruz, Jose N. da;Ortega, Edwin M.M.;Cordeiro, Gauss M.;Suzuki, Adriano K.;Mialhe, Fabio L.
    • Communications for Statistical Applications and Methods
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    • v.24 no.3
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    • pp.271-290
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    • 2017
  • We study a bivariate response regression model with arbitrary marginal distributions and joint distributions using Frank and Clayton's families of copulas. The proposed model is used for fitting dependent bivariate data with explanatory variables using the log-odd log-logistic Weibull distribution. We consider likelihood inferential procedures based on constrained parameters. For different parameter settings and sample sizes, various simulation studies are performed and compared to the performance of the bivariate odd-log-logistic-Weibull regression model. Sensitivity analysis methods (such as local and total influence) are investigated under three perturbation schemes. The methodology is illustrated in a study to assess changes on schoolchildren's oral health-related quality of life (OHRQoL) in a follow-up exam after three years and to evaluate the impact of caries incidence on the OHRQoL of adolescents.

A class of accelerated sequential procedures with applications to estimation problems for some distributions useful in reliability theory

  • Joshi, Neeraj;Bapat, Sudeep R.;Shukla, Ashish Kumar
    • Communications for Statistical Applications and Methods
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    • v.28 no.5
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    • pp.563-582
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    • 2021
  • This paper deals with developing a general class of accelerated sequential procedures and obtaining the associated second-order approximations for the expected sample size and 'regret' (difference between the risks of the proposed accelerated sequential procedure and the optimum fixed sample size procedure) function. We establish that the estimation problems based on various lifetime distributions can be tackled with the help of the proposed class of accelerated sequential procedures. Extensive simulation analysis is presented in support of the accuracy of our proposed methodology using the Pareto distribution and a real data set on carbon fibers is also analyzed to demonstrate the practical utility. We also provide the brief details of some other inferential problems which can be seen as the applications of the proposed class of accelerated sequential procedures.

Current Situation of the Computer-Assisted Statistical Surveys and Its Prospects (컴퓨터 이용 통계조사의 현황과 전망)

  • 이계오
    • Proceedings of the Korean Association for Survey Research Conference
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    • 2000.06a
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    • pp.137-159
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    • 2000
  • In this paper, the following facts have been reviewed: First, statistics should have the characteristics of descriptive, inferential, and applicative statistics in "information-Knowledge Society." Second, the computer has been employed in the process data collection and data analysis for producing the statistics with timeliness and efficiency. Third, we have to develop a statistical development plan which lays emphasis on the production of applicative statistics in the coming "Internet Cyber Society." In addition, we investigaated statistical survey methods. The prospects of internet surveys were also investigated here. On the basis of the above review and investigation. we suggested "an integrated system of computer-assisted statistical surveys" that can be applied to all kinds of surveys and statistics.nds of surveys and statistics.

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Current Situation of the Computer-Assisted Statistical Surveys and Its Prospects (컴퓨터 이용 통계조사의 현황과 전망)

  • Lee, Kay-O
    • Survey Research
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    • v.1 no.2
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    • pp.137-159
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    • 2000
  • In this paper, the following facts have been reviewed: First, statistics should have the characteristics of descriptive, inferential, and applicative statistics in "information-Knowledge Society." Second, the computer has been employed in the process of data collection and data analysis for producing the statistics with timeliness and efficiency. Third. we have to develop a statistical development plan which lays emphasis on the production of applicative statistics in the coming "Internet Cyber Society" In addition, we investigated overall status of computer utilization, and the process of the development of computer-assisted statistical survey methods. The prospects of internet surveys were also investigated here. On the basis of the above review and investigation, we suggested "an integrated system of computer-assisted statistical surveys" that can be applied to all kinds of surveys and statistics.

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An Evaluation of the Statistical Techniques Used in Papers of the Journal of Sasang Constitutional Medicine (2000-2009) (최근 10년간(2000-2009) 사상체질의학회지 게재논문의 통계분석방법에 대한 연구)

  • Park, Ki-Hyun;Kim, Sang-Hyuk;Kim, Hong-Gie;Lee, Si-Woo
    • Journal of Sasang Constitutional Medicine
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    • v.22 no.4
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    • pp.49-55
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    • 2010
  • 1. Objectives The purpose of this study is to assess the statistical methods used in the Journal of Sasang Constitutional Medicine and to identify the types of errors in the statistical analysis. 2. Methods We have reviewed quantitative articles published in the Journal of Sasang Constitutional Medicine from 2000 to 2009. Except for the case report, a total of 505 articles was reviewed by year. We focused on the methods of statistics in these articles. We have analysed the number of thesis used the statistical methods, the number of the statistical methods, the types of the statistical methods, and the errors of the statistical methods with the object of 202 thesis used the statistical method. 3. Results 1. Of the 370 articles, 202 used inferential statistics. 2. The most dominant was the thesis with one type of the statistical method forming 61.9% (125 thesis) of the total. 3. The ANOVA was the statistic of choice overall (40.1%), followed by the t-test (35.6%). 4. By examining the errors of the statistical methods, there were 49 thesis with errors among 81 thesis using ANOVA, 25 thesis among 72 thesis using t-test, and 18 over 62 thesis using chi-squared test. 4. Conclusions We have found various mistakes or misuses in the applications of statistical methodologies in the articles published in the Journal of Sasang Constitutional Medicine. It is necessary to present the cases of inappropriate statistical methods in order to improve the quality of academic researches. So long as Sasang constitutional medicine uses the statistical methods, researchers should fully examine and be aware of the statistical methods which they wish to use through other research articles, and statistic publications.

Cure rate proportional odds models with spatial frailties for interval-censored data

  • Yiqi, Bao;Cancho, Vicente Garibay;Louzada, Francisco;Suzuki, Adriano Kamimura
    • Communications for Statistical Applications and Methods
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    • v.24 no.6
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    • pp.605-625
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    • 2017
  • This paper presents proportional odds cure models to allow spatial correlations by including spatial frailty in the interval censored data setting. Parametric cure rate models with independent and dependent spatial frailties are proposed and compared. Our approach enables different underlying activation mechanisms that lead to the event of interest; in addition, the number of competing causes which may be responsible for the occurrence of the event of interest follows a Geometric distribution. Markov chain Monte Carlo method is used in a Bayesian framework for inferential purposes. For model comparison some Bayesian criteria were used. An influence diagnostic analysis was conducted to detect possible influential or extreme observations that may cause distortions on the results of the analysis. Finally, the proposed models are applied for the analysis of a real data set on smoking cessation. The results of the application show that the parametric cure model with frailties under the first activation scheme has better findings.

The Effective Training Method for the Statistical Classification of Remotely Sensed Imagery (위성영상의 통계적 분류를 위한 유효 트레이닝 기법에 관한 연구)

  • 이병길;김용일;어양담
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.17 no.3
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    • pp.225-231
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    • 1999
  • In statistical analysis of remotely sensed data, means and variances of each classes are used as the basis of statistical similarity determination. Therefore, the overall accuracy of classification is affected by the training results. It is assumed that the ideal distributions of pixel values follow normal distributions, but practically they have some aggregations and biases. non anomalies of distribution can affect the classification results greatly as well as the variances of training results. In this study, relationships between the inferential variances of the training sets and the distributions of pixel values are examined. and the resulting changes of classification results are studied. Furthermore, the training method which minimizes the effect of underestimation of variances is proposed.

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Improving the Performance of Threshold Bootstrap for Simulation Output Analysis (시뮬레이션 출력분석을 위한 임계값 부트스트랩의 성능개선)

  • Kim, Yun-Bae
    • Journal of Korean Institute of Industrial Engineers
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    • v.23 no.4
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    • pp.755-767
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    • 1997
  • Analyzing autocorrelated data set is still an open problem. Developing on easy and efficient method for severe positive correlated data set, which is common in simulation output, is vital for the simulation society. Bootstrap is on easy and powerful tool for constructing non-parametric inferential procedures in modern statistical data analysis. Conventional bootstrap algorithm requires iid assumption in the original data set. Proper choice of resampling units for generating replicates has much to do with the structure of the original data set, iid data or autocorrelated. In this paper, a new bootstrap resampling scheme is proposed to analyze the autocorrelated data set : the Threshold Bootstrap. A thorough literature search of bootstrap method focusing on the case of autocorrelated data set is also provided. Theoretical foundations of Threshold Bootstrap is studied and compared with other leading bootstrap sampling techniques for autocorrelated data sets. The performance of TB is reported using M/M/1 queueing model, else the comparison of other resampling techniques of ARMA data set is also reported.

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Children's Emotional inference According to the Character's Personality Traits and Emotional Situations (과제인물의 성격특성과 정서상황에 따른 아동의 정서추론)

  • Chung Ha Na;Yi Soon Hyung
    • Journal of the Korean Home Economics Association
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    • v.43 no.5 s.207
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    • pp.221-234
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    • 2005
  • This study investigated the emotional inferences depending on the children's age, character's personality traits, and emotional situations. One hundred three subjects (34 3-year-olds, 33 5-year-olds and 36 7-year-olds) were recruited from 3 daycare centers and 1 elementary school. Eight stories, consisting of four personality traits (positive-'active','helpful', negative-'selfish','mean') and two emotional situations (equivocal and unequivocal situation), were presented with three pictures each. The statistical methods adopted for the data analysis were repeated measure ANOVA, and paired t-test. The results showed that the 3-year-olds showed lower scores of emotional inferences than the 5- and 7-year-olds. However, there were no significant differences between the 5- and 7-year-olds. Children showed more personal inferential responses in the negative personality trait and equivocal situation.