Brazilian Journal of Probability and Statistics

Bimodal extension based on the skew-$t$-normal distribution

Mehdi Amiri, Héctor W. Gómez, Ahad Jamalizadeh, and Mina Towhidi

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In this paper, a skew and uni-/bi-modal extension of the Student-$t$ distribution is considered. This model is more flexible and has wider ranges of skewness and kurtosis than the other skew distributions in literature. Fisher information matrix for the proposed model and some submodels are derived. With a simulation study and some real data sets, applicability of the proposed models are illustrated.

Article information

Braz. J. Probab. Stat., Volume 33, Number 1 (2019), 2-23.

Received: April 2015
Accepted: August 2017
First available in Project Euclid: 14 January 2019

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Skewness kurtosis bimodal density Fisher information matrix maximum likelihood estimation


Amiri, Mehdi; Gómez, Héctor W.; Jamalizadeh, Ahad; Towhidi, Mina. Bimodal extension based on the skew-$t$-normal distribution. Braz. J. Probab. Stat. 33 (2019), no. 1, 2--23. doi:10.1214/17-BJPS372.

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