• Title/Summary/Keyword: Goodness-of-fit statistic

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Goodness-of-fit tests for a proportional odds model

  • Lee, Hyun Yung
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.6
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    • pp.1465-1475
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    • 2013
  • The chi-square type test statistic is the most commonly used test in terms of measuring testing goodness-of-fit for multinomial logistic regression model, which has its grouped data (binomial data) and ungrouped (binary) data classified by a covariate pattern. Chi-square type statistic is not a satisfactory gauge, however, because the ungrouped Pearson chi-square statistic does not adhere well to the chi-square statistic and the ungrouped Pearson chi-square statistic is also not a satisfactory form of measurement in itself. Currently, goodness-of-fit in the ordinal setting is often assessed using the Pearson chi-square statistic and deviance tests. These tests involve creating a contingency table in which rows consist of all possible cross-classifications of the model covariates, and columns consist of the levels of the ordinal response. I examined goodness-of-fit tests for a proportional odds logistic regression model-the most commonly used regression model for an ordinal response variable. Using a simulation study, I investigated the distribution and power properties of this test and compared these with those of three other goodness-of-fit tests. The new test had lower power than the existing tests; however, it was able to detect a greater number of the different types of lack of fit considered in this study. I illustrated the ability of the tests to detect lack of fit using a study of aftercare decisions for psychiatrically hospitalized adolescents.

Data-Driven Smooth Goodness of Fit Test by Nonparametric Function Estimation

  • Kim, Jongtae
    • Communications for Statistical Applications and Methods
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    • v.7 no.3
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    • pp.811-816
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    • 2000
  • The purpose of this paper is to study of data-driven smoothing goodness of it test, when the hypothesis is complete. The smoothing goodness of fit test statistic by nonparametric function estimation techniques is proposed in this paper. The results of simulation studies for he powers of show that the proposed test statistic compared well to other.

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Goodness-of-Fit Tests for the Ordinal Response Models with Misspecified Links

  • Jeong, Kwang-Mo;Lee, Hyun-Yung
    • Communications for Statistical Applications and Methods
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    • v.16 no.4
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    • pp.697-705
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    • 2009
  • The Pearson chi-squared statistic or the deviance statistic is widely used in assessing the goodness-of-fit of the generalized linear models. But these statistics are not proper in the situation of continuous explanatory variables which results in the sparseness of cell frequencies. We propose a goodness-of-fit test statistic for the cumulative logit models with ordinal responses. We consider the grouping of a dataset based on the ordinal scores obtained by fitting the assumed model. We propose the Pearson chi-squared type test statistic, which is obtained from the cross-classified table formed by the subgroups of ordinal scores and the response categories. Because the limiting distribution of the chi-squared type statistic is intractable we suggest the parametric bootstrap testing procedure to approximate the distribution of the proposed test statistic.

Basic Statistics in Quantile Regression

  • Kim, Jae-Wan;Kim, Choong-Rak
    • The Korean Journal of Applied Statistics
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    • v.25 no.2
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    • pp.321-330
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    • 2012
  • In this paper we study some basic statistics in quantile regression. In particular, we investigate the residual, goodness-of-fit statistic and the effect of one or few observations on estimates of regression coefficients. In addition, we compare the proposed goodness-of-fit statistic with the statistic considered by Koenker and Machado (1999). An illustrative example based on real data sets is given to see the numerical performance of the proposed basic statistics.

On the Goodness-of-fit Test in Regression Using the Difference Between Nonparametric and Parametric Fits

  • Hong, Chang-Kon;Joo, Jae-Seon
    • Communications for Statistical Applications and Methods
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    • v.8 no.1
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    • pp.1-14
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    • 2001
  • This paper discusses choosing the weight function of the Hardle and Mammen statistic in nonparametric goodness-of-fit test for regression curve. For this purpose, we modify the Hardle and Mammen statistic and derive its asymptotic distribution. Some results on the test statistic from the wild bootstrapped sample are also obtained. Through Monte Carlo experiment, we check the validity of these results. Finally, we study the powers of the test and compare with those of the Hardle and Mammen test through the simulation.

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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.

Quantiles for Shapiro-Francia W' Statistic

  • Rahman, Mezbahur;Ali, Mir Masoom
    • Journal of the Korean Data and Information Science Society
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    • v.10 no.1
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    • pp.1-10
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    • 1999
  • Table of the empirical quantiles for the well known Shapiro-Francia W' goodness of fit statistic is produced which is more accurate than the existing ones. Prediction equation for the quantiles of W' statistic for sample sizes 30 or more we developed. The process of computing the expected values for the standard normal variate is discussed. This work is intended to make the Shapiro-Francia W' statistic more accessible to the practitioner.

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On Testing Exponentiality Against HNRBUE Based on Goodness of Fit

  • Mahmoud, M.A.W.;Diab, L.S.
    • International Journal of Reliability and Applications
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    • v.8 no.1
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    • pp.27-39
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    • 2007
  • Based on goodness of fit new testing procedures are derived for testing exponentiality against harmonic new renewal better than used in expectation (HNRBUE). For this aging properties, a nonparametric procedure (U-statistic) is proposed. The percentiles of this test statistic are tabulated for sample sizes n=5(1)30(10)50. The Pitman asymptotic efficiency (PAE) of the test is calculated and compared with, the (PAE) of the test for new renewal better than used (NRBU) class of life distribution [see Mahmoud et al (2003)]. The power of this test is also calculated for some commonly used life distributions in reliability. The right censored data case is also studied. Finally, real examples are given to elucidate the use of the proposed test statistic in the reliability analysis.

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A Study on Goodness-of-fit Test for Density with Unknown Parameters

  • Hang, Changkon;Lee, Minyoung
    • Communications for Statistical Applications and Methods
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    • v.8 no.2
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    • pp.483-497
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    • 2001
  • When one fits a parametric density function to a data set, it is usually advisable to test the goodness of the postulated model. In this paper we study the nonparametric tests for testing the null hypothesis against general alternatives, when the null hypothesis specifies the density function up to unknown parameters. We modify the test statistic which was proposed by the first author and his colleagues. Asymptotic distribution of the modified statistic is derived and its performance is compared with some other tests through simulation.

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Comparison of Powers in Goodness of Fit Test of Quadratic Measurement Error Model

  • Moon, Myung-Sang
    • Communications for Statistical Applications and Methods
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    • v.9 no.1
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    • pp.229-240
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    • 2002
  • Whether to use linear or quadratic model in the analysis of regression data is one of the important problems in classical regression model and measurement error model (MEM). In MEM, four goodness of fit test statistics are available In solving that problem. Two are from the derivation of estimators of quadratic MEM, and one is from that of the general $k^{th}$-order polynomial MEM. The fourth one is derived as a variation of goodness of fit test statistic used in linear MEM. The purpose of this paper is to find the most powerful test statistic among them through the small-scale simulation.