Ma`rifat Eqtesadi

Taxes play a significant role in reducing economic inequalities. Islamic taxes will also have more distributional effects than conventional taxes due to their characteristics and religious support. In this article, using the fuzzy regression model in the environment of the Gems program, the impact of the uncertainty of Islamic and conventional taxes on the right and left width of income inequality in Iran for the period of 1375-1399 has been investigated. In fact, by using the calculation of the right and left widths, it is possible to check the impact of the uncertainty of each of the mentioned taxes on the inequality of income tithes. The results show that the payment of khums, among other taxes, strongly affects the inequality between tithes. The general conclusion of the comparison of the impact of uncertainty in the payment of Islamic and conventional taxes on the inequality of income tithes is that with the spread of Islamic taxes compared to conventional taxes, the intensity of inequality between income tithes can be reduced. Also, the results show that the uncertainty in the payment of Islamic taxes compared to conventional taxes increases the inequality between the top deciles of income. This indicates that the institutions related to tax collection still do not have the necessary tools to increase the motivation.