• Title/Summary/Keyword: test of normality

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Goodness-of-Fit Test for the Normality based on the Generalized Lorenz Curve

  • Cho, Youngseuk;Lee, Kyeongjun
    • Communications for Statistical Applications and Methods
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    • v.21 no.4
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    • pp.309-316
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    • 2014
  • Testing normality is very important because the most common assumption is normality in statistical analysis. We propose a new plot and test statistic to goodness-of-fit test for normality based on the generalized Lorenz curve. We compare the new plot with the Q-Q plot. We also compare the new test statistic with the Kolmogorov-Smirnov (KS), Cramer-von Mises (CVM), Anderson-Darling (AD), Shapiro-Francia (SF), and Shapiro-Wilks (W) test statistic in terms of the power of the test through by Monte Carlo method. As a result, new plot is clearly classified normality and non-normality than Q-Q plot; in addition, the new test statistic is more powerful than the other test statistics for asymmetrical distribution. We check the proposed test statistic and plot using Hodgkin's disease data.

Goodness-of-Fit-Test from Censored Samples

  • Cho, Young-Suk
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.1
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    • pp.41-52
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    • 2006
  • Because most common assumption is normality in statistical analysis, testing normality is very important. The Q-Q plot is a powerful tool to test normality with full samples in statistical package. But the plot can't test normality in type-II censored samples. This paper proposed the modified the Q-Q plot and the modified normalized sample Lorenz curve(NSLC) for normality test in the type-II censored samples. Using the two Hodgkin's disease data sets and the type-II censored samples, we picture the modified Q-Q plot and the modified normalized sample Lorenz curve.

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A Test for Multivariate Normality Focused on Elliptical Symmetry Using Mahalanobis Distances

  • Park, Cheol-Yong
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.4
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    • pp.1191-1200
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    • 2006
  • A chi-squared test of multivariate normality is suggested which is mainly focused on detecting deviations from elliptical symmetry. This test uses Mahalanobis distances of observations to have some power for deviations from multivariate normality. We derive the limiting distribution of the test statistic by a conditional limit theorem. A simulation study is conducted to study the accuracy of the limiting distribution in finite samples. Finally, we compare the power of our method with those of other popular tests of multivariate normality under two non-normal distributions.

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A Note on the Simple Chi-Squared Test of Multivariate Normality

  • Park, Cheol-Yong
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.2
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    • pp.423-430
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    • 2004
  • We provide the exact form of a Rao-Robson version of the chi-squared test of multivariate normality suggested by Park(2001). This test is easy to apply in practice since it is easily computed and has a limiting chi-squared distribution under multivariate normality. A self-contained formal argument is provided that it has the limiting chi-squared distribution. A simulation study is provided to study the accuracy, in finite samples, of the limiting distribution. Finally, a simulation study in a nonnormal distribution is conducted in order to compare the power of our test with those of other popular normality tests.

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A Test for Multivariate Normality Focused on Elliptical Symmetry Using Mahalanobis Distances

  • Park, Cheol-Yong
    • 한국데이터정보과학회:학술대회논문집
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    • 2006.04a
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    • pp.203-212
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    • 2006
  • A chi-squared test of multivariate normality is suggested which is mainly focused on detecting deviations from elliptical symmetry. This test uses Mahalanobis distances of observations to have some power for deviations from multivariate normality. We derive the limiting distribution of the test statistic by a conditional limit theorem. A simulation study is conducted to study the accuracy of the limiting distribution in finite samples. Finally, we compare the power of our method with those of other popular tests of multivariate normality under two non-normal distributions.

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A Simultaneous Test for Multivariate Normality and Independence with Application to Univariate Residuals

  • Park, Cheol-Yong
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.1
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    • pp.115-122
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    • 2006
  • A test is suggested for detecting deviations from both multivariate normality and independence. This test can be used for assessing the normality and independence of univariate time series residuals. We derive the limiting distribution of the test statistic and a simulation study is conducted to study the accuracy of the limiting distribution in finite samples. Finally, we apply our method to a real data of time series.

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More Powerful Test for Normality Based on the Normalized Sample Lorenz Curve (NORMALIZED SAMPLE LORENZ CURVE를 이용한 검정력이 높은 정규성 검정)

  • 강석복;조영석
    • The Korean Journal of Applied Statistics
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    • v.15 no.2
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    • pp.415-421
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    • 2002
  • Because most common assumption is normality in statistical analysis, testing normality is very important. We propose a new plot and test statistic to test for normality based on the modified Lorenz curve that is proved to be a powerful tool to measure the income inequality within a population of income receivers. We also compare the proposed test statistics with the W test (Shapiro and Wilk (1965)), TL test (Kang and Cho (1999)) in terms of the power of test through by Monte Carlo method. The proposed test is more usually powerful than the other tests except some case.

Normality Tests Using Nonparametric Rank Measures for Small Sample (소표본인 경우 비모수 순위척도를 이용한 정규성 검정)

  • Lee, Chang-Ho;Choi, Sung-Woon
    • Journal of the Korea Safety Management & Science
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    • v.10 no.3
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    • pp.237-243
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    • 2008
  • The present study proposes two normality tests using nonparametric rank measures for small sample such as modified normal probability paper(NPP) tests and modified Ryan-Joiner Test. This research also reviews various normality tests such as $X^2$ test, and Kullback-Leibler test. The proposed normality tests can be efficiently applied to the sparsity tests of factor effect or contrast using saturated design in $k^n$ factorial and fractional factorial design.

Numerical study on Jarque-Bera normality test for innovations of ARMA-GARCH models

  • Lee, Tae-Wook
    • Journal of the Korean Data and Information Science Society
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    • v.20 no.2
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    • pp.453-458
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    • 2009
  • In this paper, we consider Jarque-Bera (JB) normality test for the innovations of ARMA-GARCH models. In financial applications, JB test based on the residuals are routinely used for the normality of ARMA-GARCH innovations without a justification. However, the validity of JB test should be justified in advance of the actual practice (Lee et al., 2009). Through the simulation study, it is found that the validity of JB test depends on the shape of test statistic. Specifically, when the constant term is involved in ARMA model, a certain type of residual based JB test produces severe size distortions.

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Test of Normality Based on the Normalized Sample Lorenz Curve

  • Kang, Suk-Bok;Cho, Young-Suk
    • Communications for Statistical Applications and Methods
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    • v.8 no.3
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    • pp.851-858
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    • 2001
  • Using the normalized sample Lorenz curve which is introduced by Kang and Cho (2001), we propose the test statistics for testing of normality that is very important test in statistical analysis and compare the proposed test with the other tests in terms of the power of test through by Monte Carlo method. The proposed test is more power than the other tests except some cases

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