TOPSIS-entropy method for assessing the effectiveness of tax instruments: a case study of the Russian tax system

The objective of this study is to identify the tax instruments of the Russian tax system that exhibit the greatest fiscal and socioeconomic efficiency. Using the TOPSIS-entropy multicriteria analysis method, statistical data on tax instruments of the Russian tax system was analyzed. The analysis revealed that the tax on the use of natural resources, with an integral indicator of 0.641, exhibits the greatest fiscal efficiency. Tax instruments with the greatest tax potential were identified, including the personal property tax, which has a significant tax base. The analysis showed that the parameters of the Russian tax system largely implement the regulatory function of taxes and ensure greater economic efficiency than social efficiency. The tax on the use of natural resources has the highest integral indicator of socioeconomic efficiency (0.858), reflecting greater tax support and the creation of the most favorable tax conditions for the resource-extracting industries. This is confirmed by the values of the integrated economic efficiency indicator for corporate income tax (0.132), simplified tax system tax (0.090), and the unified agricultural tax (0.073). The study showed that taxes that should largely fulfill social functions, such as personal income tax (0.088) and personal property tax (0.063), fail to do so. The study proposed a tax function imbalance coefficient, which showed that the greatest disproportions in the implementation of fiscal and socio-economic functions are found in personal income tax (0.383) and personal property tax (0.366).