• 제목/요약/키워드: likelihood ratio statistic

검색결과 74건 처리시간 0.018초

Empirical Comparisons of Disparity Measures for Partial Association Models in Three Dimensional Contingency Tables

  • Jeong, D.B.;Hong, C.S.;Yoon, S.H.
    • Communications for Statistical Applications and Methods
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    • 제10권1호
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    • pp.135-144
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    • 2003
  • This work is concerned with comparison of the recently developed disparity measures for the partial association model in three dimensional categorical data. Data are generated by using simulation on each term in the log-linear model equation based on the partial association model, which is a proposed method in this paper. This alternative Monte Carlo methods are explored to study the behavior of disparity measures such as the power divergence statistic I(λ), the Pearson chi-square statistic X$^2$, the likelihood ratio statistic G$^2$, the blended weight chi-square statistic BWCS(λ), the blended weight Hellinger distance statistic BWHD(λ), and the negative exponential disparity statistic NED(λ) for moderate sample sizes. We find that the power divergence statistic I(2/3) and the blended weight Hellinger distance family BWHD(1/9) are the best tests with respect to size and power.

Control charts for monitoring correlation coefficients in variance-covariance matrix

  • Chang, Duk-Joon;Heo, Sun-Yeong
    • Journal of the Korean Data and Information Science Society
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    • 제22권4호
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    • pp.803-809
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    • 2011
  • Properties of multivariate Shewhart and CUSUM charts for monitoring variance-covariance matrix, specially focused on correlation coefficient components, are investigated. The performances of the proposed charts based on control statistic Lawley-Hotelling $V_i$ and likelihood ratio test (LRT) statistic $TV_i$ are evaluated in terms of average run length (ARL). For monitoring correlation coe cient components of dispersion matrix, we found that CUSUM chart based on $TV_i$ gives relatively better performances and is more preferable, and the charts based on $V_i$ perform badly and are not recommended.

Testing of Poisson Incidence Rate Restriction

  • Singh, Karan;Shanmugam, Ramalingam
    • International Journal of Reliability and Applications
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    • 제2권4호
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    • pp.263-268
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    • 2001
  • Shanmugam(1991) generalized the Poisson distribution to capture a restriction on the incidence rate $\theta$ (i.e. $\theta$$\beta$, an unknown upper limit), and named it incidence rate restricted Poisson (IRRP) distribution. Using Neyman's C($\alpha$) concept, Shanmugam then devised a hypothesis testing procedure for $\beta$ when $\theta$ remains unknown nuisance parameter. Shanmugam's C ($\alpha$) based .results involve inverse moments which are not easy tools, This article presents an alternate testing procedure based on likelihood ratio concept. It turns out that likelihood ratio test statistic offers more power than the C($\alpha$) test statistic. Numerical examples are included.

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Mutual Information and Redundancy for Categorical Data

  • Hong, Chong-Sun;Kim, Beom-Jun
    • Communications for Statistical Applications and Methods
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    • 제13권2호
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    • pp.297-307
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    • 2006
  • Most methods for describing the relationship among random variables require specific probability distributions and some assumptions of random variables. The mutual information based on the entropy to measure the dependency among random variables does not need any specific assumptions. And the redundancy which is a analogous version of the mutual information was also proposed. In this paper, the redundancy and mutual information are explored to multi-dimensional categorical data. It is found that the redundancy for categorical data could be expressed as the function of the generalized likelihood ratio statistic under several kinds of independent log-linear models, so that the redundancy could also be used to analyze contingency tables. Whereas the generalized likelihood ratio statistic to test the goodness-of-fit of the log-linear models is sensitive to the sample size, the redundancy for categorical data does not depend on sample size but its cell probabilities itself.

Tests for homogeneity of proportions in clustered binomial data

  • Jeong, Kwang Mo
    • Communications for Statistical Applications and Methods
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    • 제23권5호
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    • pp.433-444
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    • 2016
  • When we observe binary responses in a cluster (such as rat lab-subjects), they are usually correlated to each other. In clustered binomial counts, the independence assumption is violated and we encounter an extra-variation. In the presence of extra-variation, the ordinary statistical analyses of binomial data are inappropriate to apply. In testing the homogeneity of proportions between several treatment groups, the classical Pearson chi-squared test has a severe flaw in the control of Type I error rates. We focus on modifying the chi-squared statistic by incorporating variance inflation factors. We suggest a method to adjust data in terms of dispersion estimate based on a quasi-likelihood model. We explain the testing procedure via an illustrative example as well as compare the performance of a modified chi-squared test with competitive statistics through a Monte Carlo study.

On Testing Equality of Matrix Intraclass Covariance Matrices of $K$Multivariate Normal Populations

  • Kim, Hea-Jung
    • Communications for Statistical Applications and Methods
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    • 제7권1호
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    • pp.55-64
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    • 2000
  • We propose a criterion for testing homogeneity of matrix intraclass covariance matrices of K multivariate normal populations, It is based on a variable transformation intended to propose and develop a likelihood ratio criterion that makes use of properties of eigen structures of the matrix intraclass covariance matrices. The criterion then leads to a simple test that uses an asymptotic distribution obtained from Box's (1949) theorem for the general asymptotic expansion of random variables.

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Testing Homogeneity of Diagonal Covariance Matrices of K Multivariate Normal Populations

  • Kim, Hea-Jung
    • Communications for Statistical Applications and Methods
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    • 제6권3호
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    • pp.929-938
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    • 1999
  • We propose a criterion for testing homogeneity of diagonal covariance matrices of K multivariate normal populations. It is based on a factorization of usual likelihood ratio intended to propose and develop a criterion that makes use of properties of structures of the diagonal convariance matrices. The criterion then leads to a simple test as well as to an accurate asymptotic distribution of the test statistic via general result by Box (1949).

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On Bootstrapping; Bartlett Adjusted Empirical Likelihood Ratio Statistic in Regression Analysis

  • Woochul Kim;Duk-Hyun Ko;Keewon Lee
    • Journal of the Korean Statistical Society
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    • 제25권2호
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    • pp.205-216
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    • 1996
  • The bootstrap calibration method for empirical likelihood is considered to make a confidence region for the regression coefficients. Asymptotic properties are studied regarding the coverage probability. Small sample simulation results reveal that the bootstrap calibration works quite well.

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Diagnostics for Heteroscedasticity in Mixed Linear Models

  • Ahn, Chul-Hwan
    • Journal of the Korean Statistical Society
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    • 제19권2호
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    • pp.171-175
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    • 1990
  • A diagnostic test for detecting nonconstant variance in mixed linear models based on the score statistic is derived through the technique of model expansion, and compared to the log likelihood ratio test.

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비정규 잡음 환경에서 협력 무선인지 네트워크를 위한 순서 기반 스펙트럼 센싱 기법 (An Order Statistic-Based Spectrum Sensing Scheme for Cooperative Cognitive Radio Networks in Non-Gaussian Noise Environments)

  • 조형원;이영포;윤석호;배석능;이광억
    • 한국통신학회논문지
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    • 제37A권11호
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    • pp.943-951
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    • 2012
  • 본 논문에서는 비정규 충격성 잡음 환경에서 협력 무선인지 네트워크를 위한 순서 기반 스펙트럼 센싱 기법을 제안한다. 구체적으로는 잡음을 이변수 등방형 대칭 알파 안정 (bivariate isotropic symmetric ${\alpha}$-stable) 분포를 따르는 것으로 모형화하고, 그에 알맞은 관측 샘플의 순서와 일반화된 우도비 검정 기반 협력 스펙트럼 센싱 기법을 제안한다. 모의실험을 통해 비정규 잡음 환경에서 제안한 기법이 기존의 기법에 비해 더 좋은 스펙트럼 센싱성능을 가짐을 보인다.