• 제목/요약/키워드: normality tests

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Nonparametric Test for Used Better Than Aged in Convex Ordering Class(UBAC) of Life Distributions with Hypothesis Testing Applications

  • Abu-Youssef, S.E.
    • International Journal of Reliability and Applications
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    • 제10권2호
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    • pp.81-88
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    • 2009
  • A non-parametric procedure is presented for testing exponentially against used better than aged in convex ordering class (UBAC) of life distributions based on u-test. Convergence of the proposed statistic to the normal distribution is proved. Selected critical values are tabulated for sample sizes 5(5)40. The Pitman asymptotic relative efficiency of my proposed test to tests of other classes is studied. An example of 40 patients suffering from blood cancer disease demonstrates practical application of the proposed test.

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Rank Tests for Multivariate Linear Models in the Presence of Missing Data

  • Lee, Jae-Won;David M. Reboussin
    • Journal of the Korean Statistical Society
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    • 제26권3호
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    • pp.319-332
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    • 1997
  • The application of multivariate linear rank statistics to data with item nonresponse is considered. Only a modest extension of the complete data techniques is required when the missing data may be thought of as a random sample, and an appropriate modification of the covariances is derived. A proof of the asymptotic multivariate normality is given. A review of some related results in the literature is presented and applications including longitudinal and repeated measures designs are discussed.

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A Family of Tests for Trend Change in Mean Residual Life with Known Change Point

  • Na, Myung-Hwan;Kim, Jae-Joo
    • Communications for Statistical Applications and Methods
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    • 제7권3호
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    • pp.789-798
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    • 2000
  • The mean residual function is the expected remaining life of an item at age x. The problem of trend change in the mean residual life is great interest in the reliability and survival analysis. In this paper, we develop a family of test statistics for testing whether or not the mean residual life changes its trend. The asymptotic normality of the test statistics is established. Monte Carlo simulations are conducted to study the performance of our test statistics.

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A Goodness of Fit Approach to Testing Exponential Better than Used (EBU) Life Distributions

  • Abu-Youssef, S.E.
    • International Journal of Reliability and Applications
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    • 제9권1호
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    • pp.71-78
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    • 2008
  • Based on the goodness of fit approach, a new test is presented for testing exponentiality versus exponential better (worse) than used (EBU (EWU)) class of life distributions. The new test is much simpler to compute, asymptotically normal, enjoys good power and performs better than previous tests in terms of power and Pitman asymptotic efficiencies for several alternatives.

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Testing NBUCA Class of Life Distribution Using U-Test

  • Al-Nachawati, H.
    • International Journal of Reliability and Applications
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    • 제8권2호
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    • pp.125-135
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    • 2007
  • In this paper, testing exponentiality against new better than used in convex average and denote by (NBUCA), or its dual (NWUCA) is investigated through the U-test. The percentiles of these tests are tabulated for samples sizes n = 5(1)40. The power estimates of the test are simulated for some commonly used distributions in reliability. Pitman's asymptotic efficiency of the test is calculated and compared. Data of 40 patients suffering from blood cancer disease (Leukemia) is considered as a practical application of the proposed test in the medical sciences.

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Topographical measurement of the attachments of the central band of the interosseous membrane on interosseous crests of the radius and ulna

  • Jang, Suk-Hwan;Kim, Kyung-Whan;Jang, Hyo Seok;Kim, Yeong-Seok;Kim, Hojin;Kim, Youngbok
    • Clinics in Shoulder and Elbow
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    • 제24권4호
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    • pp.253-260
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    • 2021
  • Background: To suggest a reasonable isometric point based on the anatomical consistency of interosseous membrane (IOM) attachment in association with topographic characteristics of the interosseous crests, the footprints of the central band (CB) of the IOM on the radial and ulnar interosseous crests (RIC and UIC) were measured. Methods: We measured the distance from the CB footprints from each apex of both interosseous crests in 14 cadavers and the angles between the forearm axis of rotation (AOR) and the distal slopes of the RIC and UIC in 33 volunteers. Results: The CB footprints lay on the downslope of both interosseous crests with its upper margin on average 3-mm proximal from the RIC's apex consistently in the radial length, showing normality (p>0.05), and on average 16-mm distal from the UIC's apex on the ulna without satisfying normality (p<0.05). The average angle between the UIC's distal slope and the AOR was 1.3°, and the RIC's distal slope to the AOR was 14.0°, satisfying the normality tests (p>0.05), and there was no side-to-side difference in both forearms (p<0.05). Conclusions: The CB attached to the downslope just distal to the RIC's apex constrains the radius to the UIC that coincides with the AOR of the forearm circumduction, maintaining itself both isometrically and isotonically.

Testing the Equality of Several Correlation Coefficients by Permutation Method

  • Um, Yonghwan
    • 한국컴퓨터정보학회논문지
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    • 제27권6호
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    • pp.167-174
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    • 2022
  • 본 논문에서는 여러 개의 독립적인 모집단들 사이에서 상관계수들의 등가성에 대한 퍼뮤테이션 검정을 조사한다. 퍼뮤테이션 검정은 관측값들의 상호교환성에 기초하는 비모수적인 검정 방법이며 상호교환성이란 독립적이고 동일한 확률변수들의 개념을 일반화한 개념이다. 퍼뮤테이션 검정을 사용함으로써 근사적으로 정확한 검정에 가까운 검정을 실시할 수 있다. 퍼뮤테이션 검정은 근사적으로 보수적인 검정만큼의 검정력을 지니며, 표본의 크기가 작거나 정규성 가정이 충족되지 않을 때 유용한 방법이다. 본 논문에서는 먼저 상관계수들의 등가성을 검정하는 모수적인 방법들을 소개하고 이들을 퍼뮤테이션 검정과 비교한다. 끝으로 모든 검정들은 Iris 데이터를 예를 들어 비교된다.

설명변수 차원 축소에 관한 비모수적 검정 (Nonparametric test on dimensionality of explantory variables)

  • 서한손
    • 응용통계연구
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    • 제8권2호
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    • pp.65-75
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    • 1995
  • 설명변수 축소방법들인 Sliced Inverse Regression과 Principal Hessian Directions에서는 효과적 차원축소공간의 차원을 결정하기 위하여 설명변수의 정규성과 충분한 수의 자료가 요구되는 점근적검정(asymptotic test)을 제시하고 있다. 본 연구에서는 Cook과 Weisberg(1991)가 제안하였던 순열검정통계량(permutation test statistic)을 개발하여 SIR과 PHD에서 제시된 점근적 검정 통계량과 검정력을 비교하기로 한다.

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Monitoring of Gene Regulations Using Average Rank in DNA Microarray: Implementation of R

  • Park, Chang-Soon
    • Journal of the Korean Data and Information Science Society
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    • 제18권4호
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    • pp.1005-1021
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    • 2007
  • Traditional procedures for DNA microarray data analysis are to preprocess and normalize the gene expression data, and then to analyze the normalized data using statistical tests. Drawbacks of the traditional methods are: genuine biological signal may be unwillingly eliminated together with artifacts, the limited number of arrays per gene make statistical tests difficult to use the normality assumption or nonparametric method, and genes are tested independently without consideration of interrelationships among genes. A novel method using average rank in each array is proposed to eliminate such drawbacks. This average rank method monitors differentially regulated genes among genetically different groups and the selected genes are somewhat different from those selected by traditional P-value method. Addition of genes selected by the average rank method to the traditional method will provide better understanding of genetic differences of groups.

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Nonparametric Tests for Detecting Greater Residual Life Times

  • Lim, Jae-Hak;Ibrahim A. Ahmad;Park, Dong-Ho
    • 한국신뢰성학회:학술대회논문집
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    • 한국신뢰성학회 2004년도 정기학술대회
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    • pp.167-175
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    • 2004
  • A nonparametric procedure is proposed to test the exponentiality against the hypothesis that one life distribution has a greater residual life times than the other life distribution. Such a hypothesis turns out to be equivalent to the one that one failure rate is greater than the other and so the proposed test works as a competitor to more IFR tests by Kochar (1979, 1981) and Cheng (1985). Our test statistic utilizes the U-statistics theory and a large sample nonpara metric test is established. The power of the proposed test is discussed by calculating the Pitman asymptotic relative efficiencies against several alter native hypotheses. A numerical example is presented to exemplify the proposed test.

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