• Title/Summary/Keyword: Two-sample linear rank tests

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Two-sample Linear Rank Tests for Efficient Edge Detection in Noisy Images (잡음영상에서 효과적인 에지검출을 위한 이표본 선형 순위 검정법)

  • Lim Dong-Hoon
    • Journal of the Korea Society of Computer and Information
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    • v.11 no.4 s.42
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    • pp.9-15
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    • 2006
  • In this paper we propose Wilcoxon test, Median test and Van der Waerden test such as linear rank tests in two-sample location problem for detecting edges effectively in noisy images. These methods are based on detecting image intensity changes between two pixel neighborhoods using an edge-height model to perform effectively on noisy images. The neighborhood size used here is small and its shape is varied adaptively according to edge orientations. We compare and analysis the performance of these statistical edge detectors on both natural images and synthetic images with and without noise.

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Comparing the empirical powers of several independence tests in generalized FGM family

  • Zargar, M.;Jabbari, H.;Amini, M.
    • Communications for Statistical Applications and Methods
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    • v.23 no.3
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    • pp.215-230
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    • 2016
  • The powers of some tests for independence hypothesis against positive (negative) quadrant dependence in generalized Farlie-Gumbel-Morgenstern distribution are compared graphically by simulation. Some of these tests are usual linear rank tests of independence. Two other possible rank tests of independence are locally most powerful rank test and a powerful nonparametric test based on the $Cram{\acute{e}}r-von$ Mises statistic. We also evaluate the empirical power of the class of distribution-free tests proposed by Kochar and Gupta (1987) based on the asymptotic distribution of a U-statistic and the test statistic proposed by $G{\ddot{u}}ven$ and Kotz (2008) in generalized Farlie-Gumbel-Morgenstern distribution. Tests of independence are also compared for sample sizes n = 20, 30, 50, empirically. Finally, we apply two examples to illustrate the results.

The Admissibility of Some Nonparametric Tests

  • Li, Seung-Chun
    • Journal of the Korean Statistical Society
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    • v.26 no.2
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    • pp.223-229
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    • 1997
  • It is demonstrated that many standard nonparametric test such as the Mann-Whitney-Wilcoxon test, the Fisher-Yates test, the Savage test and the median test are admissible for a two-sample nonparametric testing problem. The admissibility of the Kruskal-Wallis test is demonstrated for a nonparametric one-way layout testing problem.

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Multivariate Nonparametric Tests for Grouped and Right Censored Data

  • Park Hyo-Il;Na Jong-Hwa;Hong Seungman
    • International Journal of Reliability and Applications
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    • v.6 no.1
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    • pp.53-64
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    • 2005
  • In this paper, we propose a nonparametric test procedure for the multivariate, grouped and right censored data for two sample problem. For the construction of the test statistic, we use the linear rank statistics for each component and apply the permutation principle for obtaining the null distribution. For the large sample case, the asymptotic distribution is derived under the null hypothesis with the additional assumption that two censoring distributions are also equal. Finally, we illustrate our procedure with an example and discuss some concluding remarks. In appendices, we derive the expression of the covariance matrix and prove the asymptotic distribution.

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