چکیده:
Access to information regarding the volume of the underground economy and the extent of tax evasion is important for macroeconomic policies. In this article, we use fuzzy sets and logic to create an annual time series for the underground (unobservable) economy and tax evasion in Iran for the time period (1343-1378). Two input variables (inputs) used are the effective tax rate and the regulatory index. The fuzzy logic approach to the measurement problem is somewhat subjective, but the results are quite robust and selectable.
خلاصه ماشینی:
In this article, we use fuzzy sets and fuzzy logic to create an annual time series for the underground (unobservable) economy and tax evasion in Iran for the period (1343 - 1378).
Having information regarding the volume of the underground economy and the size of tax evasion is of great importance for economic policymakers, especially tax authorities (fiscal policymakers), in filling the Tax-Gap. Additionally, this issue has been considered for determining the effectiveness of monetary and fiscal policies, economic growth, and income distribution.
These methods include examining and studying tax liability, using the main differences between national income and national expenditure (which is accompanied by value judgments), observing fluctuations in the labor force participation rate, Cagan's (1958) cash ratio method and others, Fig's (1979) monetary exchange method, and the use of the "unobservable variable structure model"; the use of physical input (electricity) is another estimation method.
Giles (2000), using fuzzy logic and set theory, has created a time series of the underground economy for New Zealand.
Therefore, in the basic approach we choose, we first specify the fuzzy sets associated with the values of the two causal variables, then for each variable in each year, the membership values are assigned to subjective levels, and then decision rules are established to determine a level for the underground economy index using fuzzy operators.
5- Final Results We have balanced the value indices obtained for each year (1) so that the underground economy series can be obtained in terms of official Gross Domestic Product (GDP).
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