Universal Journal of Mathematics and Mathematical Sciences

The Universal Journal of Mathematics and Mathematical Sciences promotes the publication of articles in interdisciplinary fields such as finance, bioinformatics, and engineering, as well as core topics in mathematics. It encourages innovative ideas for teaching mathematics and statistics.

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THE BIVARIATE $t$ DISTRIBUTION AND ITS GRAPHICAL ANALYSIS

Authors

  • Budi Pratikno
  • Debora Sukabhakti
  • Siti Khotijah

Keywords:

bivariate t distribution, cdf, graphs, pdf, R-code.

DOI:

https://doi.org/10.17654/2277141724009

Abstract

We re-constructed the formula of the probability density function (pdf) and the cumulative distribution function (cdf) for the bivariate t distribution. Both the formulae for pdf and cdf of the bivariate t distributions are manually re-constructed. The R-code is then used to graphically analyze pdf on several parameters, and to compute the values of the cdf.

To simulate the computation of the values of the cdf, we used several degrees of freedom (df) such as 1, 5, and 10. The results show that the values of the pdf increase as both correlation coefficient and degree  of freedom increase. The peaks of the pdf curves occur when the correlation coefficient is 0.5. The value of the cdf is greater than 0.90 (close to be one) when the df happened to be 5 and 10.

Received: July 8, 2024
Revised: August 18, 2024
Accepted: August 27, 2024

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Published

2024-09-06

Issue

Section

Articles

How to Cite

THE BIVARIATE $t$ DISTRIBUTION AND ITS GRAPHICAL ANALYSIS. (2024). Universal Journal of Mathematics and Mathematical Sciences, 20(2), 153-161. https://doi.org/10.17654/2277141724009