• 제목/요약/키워드: Hypothesis testing

검색결과 772건 처리시간 0.024초

평균과 비율 비교 (Hypothesis Testing: Means and Proportions)

  • 박선일;이영원
    • 한국임상수의학회지
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    • 제26권5호
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    • pp.401-407
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    • 2009
  • In the previous article in this series we introduced the basic concepts for statistical analysis. The present review introduces hypothesis testing for continuous and categorical data for readers of the veterinary science literature. For the analysis of continuous data, we explained t-test to compare a single mean with a hypothesized value and the difference between two means from two independent samples or between two means arising from paired samples. When the data are categorical variables, the $x^2$ test for association and homogeneity, Fisher's exact test and Yates' continuity correction for small samples, and test for trend, in which at least one of the variables is ordinal is described, together with the worked examples. McNemar test for correlated proportions is also discussed. The topics covered may provide a basic understanding of different approaches for analyzing clinical data.

통계적 가설검정으로서의 선별검사절차의 검토 (Review of Screening Procedure as Statistical Hypothesis Testing)

  • 권혁무;이민구;김상부;홍성훈
    • 품질경영학회지
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    • 제26권2호
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    • pp.39-50
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    • 1998
  • A screening procedure, where one or more correlated variables are used for screeing, is reviewed from the point of statistical hypothesis testing. Without assuming a specific probability model for the joint distribution of the performance and screening variables, some principles are provided to establish the best screeing region. A, pp.ication examples are provided for two cases; ⅰ) the case where the performance variable is dichotomous and ⅱ) the case where the performance variable is continuous. In case ⅰ), a normal model is assumed for the conditional distribution of the screening variable given the performance variable. In case ⅱ), the performance and screening variables are assumed to be jointly normally distributed.

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ISO 9001:2009 품질경영원리의 실행에 관한 연구 (A Study on ISO 9001:2009 Quality Management Principles Implementation)

  • 장경;고현민
    • 대한안전경영과학회지
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    • 제12권4호
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    • pp.199-206
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    • 2010
  • In this era of globally competitive world market, many business firms have been using ISO 9000 quality management system, whose principles are leadership, customer focus, people involvement, etc., which are expected and desired to be attained for the various long/short term goals of the business firms. This paper studies whether and how those principles are implemented in the areas of service, manufacturing, etc., and researches the regression relations between business firm's performance and those principles. Using hypothesis testing, we found and showed results which can be referenced for the higher performance of business firms and those can be added to the pool of knowledge about the ISO principles implementation in service and manufacturing industries.

Two Bayesian methods for sample size determination in clinical trials

  • Kwak, Sang-Gyu;Kim, Dal-Ho;Shin, Im-Hee;Kim, Ho-Gak;Kim, Sang-Gyung
    • Journal of the Korean Data and Information Science Society
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    • 제21권6호
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    • pp.1343-1351
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    • 2010
  • Sample size determination is very important part in clinical trials because it influences the time and the cost of the experimental studies. In this article, we consider the Bayesian methods for sample size determination based on hypothesis testing. Specifically we compare the usual Bayesian method using Bayes factor with the decision theoretic method using Bayesian reference criterion in mean difference problem for the normal case with known variances. We illustrate two procedures numerically as well as graphically.

장기 생활설계를 위한 가계 분석 (The Analysis of household Income and Expenditure For Family Economic Planning -for the Housewives in Busan-)

  • 김영숙
    • 가정과삶의질연구
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    • 제1권2호
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    • pp.59-73
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    • 1983
  • The purpose of this study is to establish the family economy planning in the side of economic welfare and to discuss its problems. Hypothesis testing and survey analysis whether nuclear family have been formed in the urban communities or not are investigated. Also, survey of family economic period are classified in the following manner. First, as the beginning of family, they are interested in savings, children's education and investment of an estate. Third, as the contracting period of family, they rely upon other's financial supports. Therefore, it is desirable for each family to establish family life cycle planning. As the results of hypothesis testing, 1) Nuclear family have been formed in urban communities. 2) The age of housewives is not concerned with whether their husband's parents live in the same house or not. 3)The age of housewives is not concerned with whether their parents lived with them or not. 4) The relationship between the age of housewives and monthly income is not significant. 5) The relationship between the age of housewives and monthly expenditure is significant. 6)The relationship between the age of housewives and monthly savings is not significant.

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픽토리얼 타이포그래피가 사용된 인쇄 광고의 커뮤니케이션 효과 연구 (Communication Effects of Print Ad Having Pictorial Typography)

  • 이광숙;곽보선
    • 한국인쇄학회지
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    • 제30권2호
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    • pp.13-22
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    • 2012
  • This research attempts to analyze communication effects of print ad having pictorial typography. 150 Questionnaires were distributed to respondents staying Daejeun City and 148 copies were retreated for five days from April 22nd to 26th, 2012. Frequency analysis, factor analysis, Cronbach's alpha for reliability analysis were utilized for data analysis with SPSS 12.0. For testing hypothesis, regression analysis was used. As result of testing hypothesis, 'informative, beneficial, creative, reliable' were partially significant to attitude towards print ad having pictorial typography. That means 'creative' and 'reliable' were insignificant, while 'informative' and 'beneficial' are significant. Variable of the most influencing on attitude towards advertising is 'informative.' 'Informative, beneficial, creative, and reliable' were partially significant to brand attitude, too. That means 'beneficial' and 'creative' were insignificant, while 'informative' and 'reliable' were significant. Variable of the most influencing on brand attitude was 'reliable.' Therefore, to enhance communication effect of print ad having pictorial typography, 'informative' and 'reliable' are most significant variables.

On inference of multivariate means under ranked set sampling

  • Rochani, Haresh;Linder, Daniel F.;Samawi, Hani;Panchal, Viral
    • Communications for Statistical Applications and Methods
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    • 제25권1호
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    • pp.1-13
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    • 2018
  • In many studies, a researcher attempts to describe a population where units are measured for multiple outcomes, or responses. In this paper, we present an efficient procedure based on ranked set sampling to estimate and perform hypothesis testing on a multivariate mean. The method is based on ranking on an auxiliary covariate, which is assumed to be correlated with the multivariate response, in order to improve the efficiency of the estimation. We showed that the proposed estimators developed under this sampling scheme are unbiased, have smaller variance in the multivariate sense, and are asymptotically Gaussian. We also demonstrated that the efficiency of multivariate regression estimator can be improved by using Ranked set sampling. A bootstrap routine is developed in the statistical software R to perform inference when the sample size is small. We use a simulation study to investigate the performance of the method under known conditions and apply the method to the biomarker data collected in China Health and Nutrition Survey (CHNS 2009) data.

소비자의 주관적 지식과 브랜드 이미지가 친환경농산물 구매에 미치는 영향 (Influences of Consumers' Subjective Knowledge and Brand Image on their Purchase of Environment-friendly Agricultural Products)

  • 서환석;황재현
    • 한국유기농업학회지
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    • 제23권2호
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    • pp.185-206
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    • 2015
  • This study aims to prepare a solution necessary for boosting the consumption of environment-friendly agricultural products, positively reflecting consumers' opinions that expect supplies of safe agricultural products to secure the domestic farms producing environment-friendly agricultural products and at the same time, to meet consumers' needs. As a result of the hypothesis testing, of the subjective knowledge in Hypothesis 1, product knowledge had an impact on attitude, while purchase knowledge and use knowledge after purchase were not significant. Of the subjective knowledge in Hypothesis 2, purchase knowledge and product knowledge had significant impacts on purchase intention. Brand image in Hypothesis 3 had a significant impact on attitude, while brand image in Hypothesis 4 had a significant impact on purchase intention. As a result of the mediated regression analysis of Hypothesis 5, all of the subjective knowledge, purchase knowledge, product knowledge and use knowledge after purchase had an impact on purchase intention, partially mediated by attitude, and brand image, too, had an impact on purchase intention, partially mediated by attitude.

A Study on Efficient Market Hypothesis to Predict Exchange Rate Trends Using Sentiment Analysis of Twitter Data

  • Komariah, Kokoy Siti;Machbub, Carmadi;Prihatmanto, Ary S.;Sin, Bong-Kee
    • 한국멀티미디어학회논문지
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    • 제19권7호
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    • pp.1107-1115
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    • 2016
  • Efficient Market Hypothesis (EMH), states that at any point in time in a liquid market security prices fully reflect all available information. This paper presents a study of proving the hypothesis through daily Twitter sentiments using the hybrid approach of the lexicon-based approach and the naïve Bayes classifier. In this research we analyze the currency exchange rate movement of Indonesia Rupiah vs US dollar as a way of testing the Efficient Market Hypothesis. In order to find a correlation between the prediction sentiments from Twitter data and the actual currency exchange rate trends we collect Twitter data every day and compute the overall sentiment to label them as positive or negative. Experimental results have shown 69% correct prediction of sentiment analysis and 65.7% correlation with positive sentiments. This implies that EMH is semi-strong Efficient Market Hypothesis, and that public information provide by Twitter sentiment correlate with changes in the exchange market trends.

일반화된 샘플링 계획에서의 가설 검정 (A Hypothesis Test under the Generalized Sampling Plan)

  • 김명수;오근태
    • 품질경영학회지
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    • 제26권4호
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    • pp.79-87
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    • 1998
  • This paper considers the problem of testing a one-sided hypothesis under the generalized sampling plan which is defined by a sequence of independent Bernoulli trials. A certain lexicographic order is defined for the boundary points of the sampling plan. It is shown that the family of probability mass function defined on the boundary points has monotone likelihood ratio, and that the test function is uniformly most powerful.

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