×

Near-exact distributions for the sphericity likelihood ratio test statistic. (English) Zbl 1138.62033

Summary: Three near-exact distributions are developed for a sphericity test statistic. The exact probability density function of this statistic is usually represented through the use of the Meijer G function, which renders the computation of quantiles impossible even for a moderately large number of variables. The main purpose of this paper is to obtain near-exact distributions that lie closer to the exact distribution than the asymptotic distributions while, at the same time, correspond to density and cumulative distribution functions practical to use, allowing for an easy determination of quantiles.
In addition to this, two asymptotic distributions that lie closer to the exact distribution than the existing ones were developed. Two measures are considered to evaluate the proximity between the exact and the asymptotic and near-exact distributions developed. As a reference we use the saddlepoint approximations developed by R. W. Butler et al. [Saddlepoint approximations for tests of block independence, sphericity and equal variances and covariances. J. R. Stat. Soc., Ser. B 55, No. 1, 171–183 (1993)] as well as the asymptotic distribution proposed by G. E. P. Box [Biometrika 36, No. 3–4, 317–346 (1949; Zbl 0035.09101)].

MSC:

62H15 Hypothesis testing in multivariate analysis
62H10 Multivariate distribution of statistics
62E20 Asymptotic distribution theory in statistics
65C60 Computational problems in statistics (MSC2010)

Citations:

Zbl 0035.09101
Full Text: DOI

References:

[1] Abramowitz, M., Stegun, I.A. (Eds.), 1974. Handbook of Mathematical Functions, ninth print. Dover, New York.; Abramowitz, M., Stegun, I.A. (Eds.), 1974. Handbook of Mathematical Functions, ninth print. Dover, New York.
[2] Alberto, R. P.; Coelho, C. A., Study of the quality of several asymptotic and near-exact approximations based on moments for the distribution of the Wilks Lambda statistic, J. Statist. Plann. Inference, 137, 1612-1626 (2007) · Zbl 1110.62021
[3] Anderson, T. W., An Introduction to Multivariate Statistical Analysis (1958), Wiley: Wiley New York · Zbl 0083.14601
[4] Berry, A., The accuracy of the Gaussian approximation to the sum of independent variates, Trans. Amer. Math. Soc., 49, 122-136 (1941) · JFM 67.0461.01
[5] Box, G. E.P., A general distribution theory for a class of likelihood criteria, Biometrika, 36, 317-346 (1949) · Zbl 0035.09101
[6] Butler, R. W.; Huzurbazar, S.; Booth, J. G., Saddlepoint approximations for tests of block independence, sphericity and equal variances and covariances, J. Roy. Statist. Soc. Ser. B, 55, 171-183 (1993) · Zbl 0800.62087
[7] Coelho, C. A., The Generalized Integer Gamma distribution—A basis for distributions in Multivariate Statistics, J. Multivariate Anal., 64, 86-102 (1998) · Zbl 0893.62046
[8] Coelho, C. A., The Generalized Near-Integer Gamma distribution: a basis for ‘near-exact’ approximations to the distributions of statistics which are the product of an odd number of independent Beta random variables, J. Multivariate Anal., 89, 191-218 (2004) · Zbl 1047.62014
[9] Coelho, C. A., The wrapped Gamma distribution and wrapped sums and linear combinations of independent Gamma and Laplace distributions, J. Statist. Theory Pract., 1, 1-29 (2007) · Zbl 1130.62011
[10] Coelho, C.A., Mexia, J.T., 2006. On the exact and near-exact distributions of statistics used in generalized F tests. Technical Report, Mathematics Department, Universidade Nova de Lisboa, submitted for publication.; Coelho, C.A., Mexia, J.T., 2006. On the exact and near-exact distributions of statistics used in generalized F tests. Technical Report, Mathematics Department, Universidade Nova de Lisboa, submitted for publication.
[11] Coelho, C. A.; Alberto, R. P.; Grilo, L. M., A Mixture of Generalized Integer Gamma distributions as the exact distribution of the product of an odd number of independent Beta random variables, J. Interdiscip. Math., 9, 229-248 (2006) · Zbl 1117.62017
[12] Consul, P. C., The exact distributions of likelihood criteria for different hypotheses. Multivariate Analysis II, (Proceedings of the Second International Symposium, Dayton, Ohio (1969), Academic Press: Academic Press New York), 171-181
[13] Esseen, C.-G., Fourier analysis of distribution functions. A mathematical study of the Laplace-Gaussian Law, Acta Math., 77, 1-125 (1945) · Zbl 0060.28705
[14] Grilo, L.; Coelho, C. A., Development and study of two near-exact approximations to the distribution of the product of an odd number of independent Beta random variables, J. Statist. Plann. Inference, 137, 1560-1575 (2007) · Zbl 1110.62020
[15] Hwang, H.-K., On convergence rates in the central limit theorems for combinatorial structures, European J. Combin., 19, 329-343 (1998) · Zbl 0906.60024
[16] Loève, M., 1977. Probability Theory, vol. I, fourth ed. Springer, New York.; Loève, M., 1977. Probability Theory, vol. I, fourth ed. Springer, New York. · Zbl 0359.60001
[17] Mauchly, J. W., Significance test for sphericity of a normal \(n\)-variate distribution, Ann. Math. Statist., 11, 204-209 (1940) · JFM 66.0641.04
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.