Inference for three-parameter 𝑴-Wright distributions with applications

Article type: Research Article

Authors: Cahoy, Dexter O.^* | Minkabo, Sharifa

Affiliations: Department of Mathematics and Statistics, College of Engineering and Science, Louisiana Tech University, Ruston, LA, USA

Correspondence: [*] Corresponding author: Dexter O. Cahoy,

Abstract: We propose point estimators for the three-parameter (location, scale, and the fractional parameter) variant distributions generated by a Wright function. We also provide uncertainty quantification procedures for the proposed point estimators under certain conditions. The class of densities includes the three-parameter one-sided and the three-parameter symmetric bimodal M-Wright family of distributions. The one-sided family naturally generalizes the Airy and half-normal models. The symmetric class includes the symmetric Airy and normal or Gaussian densities. The proposed interval estimator for the scale parameter outperformed the estimator derived in Cahoy (2012) when the location parameter is zero. We obtain the asymptotic covariance structure for the scale and fractional parameter estimators, which allows estimation of the correlation. The coverage probabilities of the interval estimators slightly depend on the proposed location parameter estimators. For the symmetric case, the sample mean (or median) is favored than the median (or mean) when the fractional parameter is greater (or lesser) than 0.39106 in terms of their asymptotic relative efficiency. The estimation algorithms were tested using synthetic data and were compared with their bootstrap counterparts. The proposed inference procedures were demonstrated on age and height data.

Keywords: Gaussian, skew-normal, M-Wright, Mittag-Leffler, skew-Laplace, Airy, skew-symmetric, Major Leaque Baseball, children heights

DOI: 10.3233/MAS-170388

Journal: Model Assisted Statistics and Applications, vol. 12, no. 2, pp. 115-125, 2017