فصلنامه تحقیقات مدلسازی اقتصادی
سال نهم شماره 33 (پاییز 1397)

The present study examined the impact of financial development on the investment of the companies listed on the Tehran Stock Exchange. To achieve this goal, data gathered from 258 companies during 2005 to 2016 and the dynamic generalized method of moments were utilized to formulate the investment model with financial constraints. The results of the study showed that these companies faced financial constraints on investment and financial development has increased their investment by reducing the financial constraints. The results also indicated that the positive effect of financial development on investment has been bigger in the case of larger companies than in smaller companies. It was further revealed that during the economic boom, financial constraints on companies were reduced and financial development led to the reinforcement of the positive effect of the boom on reduction of the companies’ financial constraints

Oil Revenue Management (ORM) has always been one of the key challenges facing the oil rich developing countries. In this regard, the main objective of this paper is to provide a dynamic macroeconometric model adapted to the state of the Iranian economy. Also, the assessment of the dynamics of the National Development Fund (NDF) and its impact on macroeconomic variables are discussed. The results of the study, based on the out of sample and the four scenarios (the existence and absence of the NDF, the change in the share of the fund from oil revenues, the Fund's floating share of oil revenues, and the scenario of the fund exposure with temporary and permanent oil shocks) indicate that, The creation of a NDF in the short term will not improve the situation of macroeconomic variables, and the positive effects of such a policy will appear in the long run. The reason for this the private sector investment was time consuming and, consequently, the increase in non-oil sector production in the economy. Nevertheless, it is possible in the short term that by designing foreign exchange or budgetary policies, the initial downturn in the level of economic activity may be reduced by the stablization of the fund. Moreover, as in the mechanism of the fund, the floating share of oil revenues (adopting an anticyclical policy in allocating oil revenues to the fund) will help to reduce the negative consequences of shocks in the short run, because the lowest initial inflationary pressures, fluctuations in exchange rates and the net debt of the public sector occurs under this scenario.

Studying currency shocks impact on the stock market could be beneficial regarding to exchange rate fluctuations caused by various exchange policies in recent years. Therefore symmetrical or asymmetrical impacts of negative and positive dollar shockwaves in the market on indexes of chemical and basic metals industry are under investigation by weekly data collected since 2006 up to 2016 as these two industries have the most non-oil exports of Iran. First existence of long-term equilibrium relationship was examined by Pesaran Bound test and confirmed. Afterwards in addition to admitting asymmetric effect of positive and negative foreign exchange shocks on the indexes using WALD test, based on the results of the main model of the research which is the Nonlinear Autoregressive Distributed Lag (NARDL), effects of increasing in dollar rate on both indexes are positive and meaningful and the effect of its decreasing is meaningless. In addition the extracted coefficients indicates deeper effects of free dollar rate on the chemical index in comparison with index of the basic metals. OPEC crude oil, which is the control variable considered in this article has a direct and significant effects on both indicators on the short and long term.

One of the factors that have a significant impact on the economic development of countries is reliance on foreign trade, and due to the dependence of countries on export earnings and the import of foreign trade, it plays an essential and indisputable role in the growth and development of different sectors. Foreign trade in agricultural products has an important role in expanding the export and import of various countries due to its high and stable value. Among the agricultural products, saffron is one of the most important export commodities of agriculture, which contributes greatly to the creation of agricultural value added. This study examines and analyzes Saffron's foreign trade network among 11 active countries including Iran in this area. The required data and statistics were collected during the years 2007-2016. Considering the geographical dispersion of the studied countries, a spatial panel model was used to analyze the factors affecting the value of saffron trade. The results of estimating OLS methods, spatial interruption and spatial error showed that import price variables per gram, export price per gram, export volume, export standards index, gross domestic product, exchange rate and government support index in agricultural sector is significant and has a positive effect on the value of trade. Positive and significant spatial dependency coefficient shows that neighborhood is an important role in increasing or decreasing trade. This means that, as long as the value of saffron trade in neighboring countries increases, the value of trade in the target country will increase as the size of the coefficient.

Money laundering is an illegal practice that legitimizes the income from illegal activities during a legitimate process.Trade-based money laundering (TBML) as one of the newest and most complicated types of money laundering has negative effects on economic, social and political aspect of a society.The most important objective of the present study is to investigate the effect of various factors on trade based money laundering in Iran using the Ferwerda Gravity model.For this purpose the effective factors on trade base money laundering between iran and some selected trade partners are investigated by the use of a random effect model during the period 1999-2012. The results indicate that a great significant part of the trade based money laundering flow between Iran and selected trade partners can be explained by the the Ferwerda Gravity model. Accordingly, gorss doimestic product(GDP), trade volume, geographical, cultural, population and attractiveness variables have a significant effect on the amount of trade based money laundering in Iran.This means that with the increase in trade flow, money laundering opportunities resulted from the trade channel, that is hidden in it, will also increase. These results can be used by policy makers for designing policies to combat money laundering particularly coming from trade channel.

The main purpose of this study is to investigate the effects of physical capital, human capital and social capital on the entrepreneurship level of individuals, using structural equations model and order logit model in Shahid Salimi industrial town of Tabriz in 2016. The data were collected form 121 economic activist who were randomly selected form the population. The empirical results show that human capital (level of education) and physical capital have negative and significant impact on the entrepreneurship level of individuals. But, human capital (level of experience) and social capital have positive and significant impact on the entrepreneurship level of individuals. In addition, attitudes, self-efficacy and expected entrepreneurial benefit have positive and significant effects on the entrepreneurship level of individuals.

In the analysis of the stock market and its market indices, instead of estimating returns and their distributions at a given time interval, it is possible to extract optimal time to achieve a certain return. In this study, the distribution of investment horizons and optimal investment horizons through inverse gamma statistics method for the indices of automobile, sugar, pharmaceutical, financial and banks industries in Tehran Stock Exchange were extracted, analyzed and compared. The results of the research show that at the levels of access to +5 percent return, automotive, sugar , banking and financial indices have shorter horizons than the total index, while in terms of access to negative returns ,the only indicator of the drug group has a longer horizon than the total index.