The BGV in the absolute inequality monitoring method is a commonly used statistic that measures the degree of discrepancy between groups and reflects the degree of deviation between a random variable and its mathematical expectation (i.e., average value). The variance is the average of the sum of the squares of the difference between individual data. In many practical problems, the study of variance (i.e., the degree of divergence) is a significant measure, with a larger BGV indicating greater inequality. The Theil index in the relative inequality monitoring method measures and calculates the relative inequality for the subgroups of the population that do not exist in the natural sequence. The T increases with an increase in the relative inequality; thus, a larger T indicates higher relative inequality without an upper limit. The Theil index shows the relative meaning rather than the absolute meaning. Therefore, T was mainly used to compare different indices in this study.\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \boldsymbol{B}\boldsymbol{G}\boldsymbol{V}={\displaystyle \sum_{\boldsymbol{j}-\boldsymbol{1}}^{\boldsymbol{J}}{\boldsymbol{P}}_{\boldsymbol{j}}}{\left({\boldsymbol{y}}_{\boldsymbol{j}}-\boldsymbol{\mu} \right)}^{\boldsymbol{2}} $$\end{document}BGV=∑j−1JPjyj−μ2