پژوهشنامه مالیات
سال هفدهم شماره 54 (پاییز 1388)

In this paper, optimal tax rates for real and legal entity income taxes have beenestimated. Optimal taxation means optimal maximization of total utility functionsof entities with regard to the budget constraint and a constraint wherein the entitiesmake their choices of labor supply taking into consideration the relationshipbetween labor and income. The foundation of our estimation has been Diamond’smodel (1998) which is itself an extended form of Diamond and Myrrless’s model(1971). This model is, in its turn, an adaptation of Saez’s model, an importantoptimal taxation model. The statistic population being used for the calculationincludes real entities in Tehran and legal entities in Tehran and Kermanshah cities.In order to cover the fairness of income distribution, the statistical data has beenclassified in terms of income deciles, and Gini coefficient was calculated as anindicator of income distribution variance. Then, an appropriate model which isassumed to have the best impact on the decrease of the Gini coefficient has beenselected. Finally, through the application of the selected model and taking intoaccount different levels labor force elasticity (for real entities) and services supplyelasticity (for legal entities), the optimal tax rates have been calculated. The resultsobtained indicate that in the Iranian tax system, the application of new rates wouldlead to a better distribution of income as well as an increase of 150% in thegovernment tax revenues. Moreover, the calculated rates are able to be interpretedon the basis of an extended formulation of Laffer’s curve.

Taking into account the role and importance of human resources as a strategic resource in organizations and bearing in mind the human capital as the second major factor involved in the collection of taxes (the first factor being the national income), the performance of human capitals in organizations, specifically in the Iranian National Tax Administration is highly important. The present paper aims at exploring the impacts of organizational health on working positive attitudes. A sample of 279 members was selected out of a statistical population of 1219 employees through a categorized random sampling in proportion to the intended sample size. The research instrument has been a questionnaire of 41 items and as for the data analysis, we have first resorted to a descriptive analysis and then, we have done inferential analyses on the data gathered within Pearson’s correlation, multi-variation regression analysis and variance analysis methodologies. Research findings indicate that there is a significant relationship between the organizational health and the employees’ working attitudes and that organizational health is of a great significance in INTA due the positive impact it has on employees’ working positive attitudes.

One of the most important components of the government budget is the taxrevenues. Having knowledge of tax volumes which can be collected from differenttax bases will help the government in optimally allocating the resources for taxcollection purposes, in doing exact financial plantings, and in identifying the extentto which citizens have participated in providing for the government’s publicexpenditures. In the present research, we have made use of statistical data of theyears 1961-2005 in order to estimate direct tax revenues (corporate income tax,individual income tax, and property tax) of the years 2010-2014 (the periodcovered by the Fifth Five-Year Economic, Social, and Cultural Development). Thefindings indicate that direct tax revenues will have an increasing trend in the fifthdevelopment plan and that the ascending trend of corporate income tax has notdeviated from its long-term trend up to the year 2005 in the sense that the collectedtaxes have all the time been less than forecasted but as from 2005 onward, due tothe addition of the performance of oil sector, the collected revenues have beenmore than forecasted. On the hand, as for individual income tax, the collectedrevenues have been less than forecasted and the revenues collected from theproperty tax category have been more than forecasted.

The present paper aims at exploring rental valuation of business properties.According to Iranian tax laws, rental valuation of properties should be done by aReal Estates Valuation Committee. This committee divides Tehran city into 162blocks and allocates a rental value/square meters in each block. The presentresearch is firstly aimed at determining indices and factors affecting the rentalvalue of business properties and at presenting an appropriate model for valuation.Then, we test a hypothesis indicating that “the valuation procedure applied byINTA is inefficient” and compare our proposed model with INTA’s method. Thestatistical population of this research includes all business units acting legallywithin the geographical area of Tehran. Through some interviews and reviews ofliterature, we have characterized 16 indices as possibly affecting the valuation ofrental value. Then, through developing a questionnaire to be filled up by experts ofTehran City Tax Affairs Organization, 9 indices have been separated as the mostimportant factors. In order to develop the model, after selecting a sample of 383,the 9 indices in question have been measured. Then, in order to develop andvalidate the intended model, we have calculated the Spearman’s correlationcoefficient along with Kendall’s coefficient in the significant level of 0.01 leadingto the separation of 6 indices followed by running a linear multiple regression andthe administrating the STEPWISE methodology. In the nest stage, estimated rentalvalues have been calculated using both our proposed model and INTA’smethodology. The two sets of values have then been compared against the actualmarket rental values. The final stage of the research includes testing the“proportion of success” hypothesis (p) as well as testing the hypothesis of“comparison of proportion of success in the two populations” (p1-p2) in order toverify the research hypotheses.

Taxes are divided into two groups of direct and indirect taxes. VAT, as a tax leviedon the consumption of goods and services, is a subcategory of indirect taxes. Thereare some barriers to the complete establishment of VAT system in Iran. Thepresent paper aims at capturing these barriers in terms of their significance andtheir priorities. To this end, “complete establishment of VAT” has been assumed tobe the dependent variable while some external/internal factors in both micro andmacro levels are handled as the independent variables. The instrument forgathering data has been a questionnaire consisting of 39 items of which the validityhas been verified by referring to experts and the reliability has been calculatedthrough Chronbach’s Alpha Coefficient methodology (0.91 for macro externalfactors, 0.75 for micro external factors, and 0.88 for internal factors). Thequestionnaire has been administrated in a sample of 150 members includingacademic faculty members and VAT staff in Guilan and Tehran provinces. Thedata gathered has been analyzed through T test and Freidman’s statistical test.According to the results obtained, all macro external factors, internal micro factorsand internal factors are respectively involved in incomplete establishment of VATin Iran and as such, all hypotheses of the research have been verified.

Nowadays, all organizations are required both to measure and manage theirintangible assets and to continuously promote these assets in order to maximize theconditions needed for achieving their goals and objectives. Organizations whichare not able to continuously promote their knowledge-based assets will inevitablysacrifice their survival. In this research we have studied such issues as theclassification of organizations’ assets, definition of intellectual capital, therationales behind focusing on intellectual capital and on measuring it, restrictionsof traditional accounting systems, models and approaches to the measurement ofintellectual capital, and (dis)advantages of internal / external reporting ofintellectual capital. Research findings obtained indicate that the organizations’achievement is a function of their ability in managing their intangible assets. Inorder to manage these assets, we should first identify and measure them. Since theIranian National Tax Administration’s duties are governance-based in nature andsince this organization is expected to provide for a considerable portion of thegovernment revenues, it is obliged to identify, assess, and manage its intangibleassets in order to make it possible to plan for making optimal use of theseresources.

In recent two decades, tax simplification has turned to be one essential componentof tax reform plans in different countries. This is not only due to negative impactscomplexity has on voluntary compliance costs resulting in tax evasion, but also dueto the fact that it is a big barrier to tax fairness and efficiency (in case of incometaxes) and as such, it is a factor far beyond administrative and compliance costs.Although a deeper understanding of various aspects of tax simplification requiresmore comprehensive investigations, this paper, which seems to be just a point ofdeparture for putting such issues under discussion in Iran, aims at exploringdifferent dimensions of tax simplification, reviewing different countries’experience, and, in the end, offering some recommendations for reforming theIranian tax system. Investigations show that a low compliance rate, a high volumeof administrative circular directives, and an inappropriate combination of taxrevenues do obviously indicate that the existing taxation system in Iran is quitecomplicated. Therefore, one of the essential challenges ahead of the Iraniantaxation system can be tax simplification, in general, and tax laws simplification, inparticular, which demands for a serious interaction between tax authority andlegislating institutions.