فصلنامه برنامه ریزی و بودجه
پیاپی 162 (پاییز 1402)

To understand the behavior of housing prices in the country it is necessary to investigate the spatial interactions of interconnected regional markets. The discussion on housing prices highlights the potential spatial heterogeneity and cross-sectional dependence in different regions. It is important to pay attention to the source of cross-sectional dependencies to better understand the dynamics of housing prices in different regions. Cross-sectional dependence can be caused either by the role of space in economic processes or by common shocks that affect the entire economy, such as the oil shock. Using a spatio-temporal housing price diffusion model, the study found that the Tehran region, as the center of economic development and oil revenues, was a dominant region, and that shocks to Tehran were propagated contemporaneously and spatially to other regions. The results show that in modeling the spatial diffusion of housing prices, financial proximity is more important than geographic proximity, and regions with stronger financial links with Tehran will be most affected by shocks to this region in the long run.

This article examines the possibility of improved social welfare as a result of the entry of a new private firm, domestic or foreign, into the upstream industry, in a situation where the upstream industry had a monopoly structure with the existence of a single government firm. A public firm can be privately or publicly managed, that is to say that it aims to either maximize profits or social welfare. The results of this study show that while in the monopoly structure, the privatization of a state-owned enterprise is an ineffective policy in terms of social welfare, the increase in competition leads to the justification of privatization, provided that the technology of the new domestic enterprise is more efficient than the state-owned enterprise within a certain range. If the new domestic enterprise is much more efficient than the state-owned enterprise or has a relatively similar technology, it will still be a suboptimal policy to privatize the state-owned enterprise. On the other hand, if the new entrant is a foreign company, the privatization of the state-owned company will be the optimal policy in a situation where the foreign company has a much more efficient technology than the state-owned company.

Considering the underground economy and the dependence of Iran's economy on oil and the influence of the tax system on oil revenues, the present study attempts to investigate the effect of oil rent on taxes, emphasizing the role of the underground economy for the period 1973-2021 in the form symmetrical and asymmetrical model. For this purpose, the size of the underground economy was calculated using the MIMIC method, representing an average of 15.2% of Iran’s economy. Then the research model was estimated by linear (symmetric) and non-linear (asymmetric) autoregressive distributed lag. The result indicates that in the symmetrical estimation, the tax is inversely affected by the oil rent, and the increase in the size of the underground economy aggravates this negative relationship. The asymmetric estimate shows that the effect of oil rent on taxation is asymmetric. First, the effect of positive oil rent shocks on taxes is much greater (more than twice) than the effect of negative oil rent shocks. Second, the expansion of the underground economy intensifies the adverse effect of negative oil rent shocks and the positive effect of negative oil rent shocks on taxes. Accordingly, it is suggested that the economic policymaker, regardless of the ups and downs of oil and the resulting rent, should diligently work to improve the efficiency of the tax system, and attempt as much as possible to control and reduce the size of the underground economy.

The 2008 U.S.A. financial crisis, which subsequently spread around the world, showed that financial distress in the banking network could spread to the network of all financial institutions and the entire economy of a country. For this reason, the development of accurate measurements of the risk of transmission of financial distress by  each bank in the banking network is very important in controlling the risk of financial intermediation in every country. However, an issue that has not received much attention in previous research is the impact of macroeconomic factors on the risk of spreading financial distress. This is important because governments can anticipate the possibility of an economic crisis by anticipating an increased risk of spreading financial helplessness and adopting monetary and fiscal policies to reduce such risk. The present study, in three stages, estimates the risk of financial distress using the KMV method, estimates the risk of transmission of financial distress using the VAR method, and models the effects of macroeconomic variables such as inflation, exchange rate, and GDP on the risk of contagion. Based on the results, it is clear that GDP has a statistically significant inverse relationship with the risk of transmission of financial distress, meaning that with increasing GDP, the risk of transmission of financial distress is expected to decrease. Also, the relationship between the exchange rate and the risk of transmission is direct and significant, and an increase in the exchange rate leads to an increase in the interdependence of financial institutions and, consequently, an increase in the risk of transmission of financial distress.

The exchange rate is one of the most important macroeconomic variables that affects different sectors of the economy from various aspects. Due to the considerable impact of industrial development on the country's economic development, this research attempts to evaluate the asymmetric effect of the exchange rate on the value added of the industrial sector for the period of 1380:1 - 1400:4, using the NARDL method. The results of the estimation show that the effect of the exchange rate on the value added of the industrial sector is asymmetric, such that an increase in the exchange rate affects the value added of the industrial sector differently from a decrease in the exchange rate. The effect of the exchange rate in the long term is such that the positive changes in the exchange rate strengthen the value added of the industrial sector, and the decrease in the exchange rate does not affect it. Therefore, the economic policymaker should abandon exchange rate suppression as an inflation control policy and allow the exchange rate to be determined based on market forces.

Due to the forward-looking nature of economic decisions, forecasting the trend of macroeconomic variables has a fundamental role in economic planning and policies. For this purpose, the present study attempts to extract the financial conditions index for the period 1991-2019, then the movement trend of macroeconomic variables has been forecasted using the Time-Varying Parameter Factor-Augmented Vector Auto-Regressive (TVP-FAVAR). The results show that the financial conditions index has undergone significant changes in recent years, especially in the 2010s, which has had an effective role in the fluctuations of other markets due to the influence and change in the behavior of other macroeconomic variables. Furthermore, forecasting the trend of macroeconomic variables also indicates that this trend is unstable; in other words, instability in the trend of macroeconomic variables is evident and we cannot expect a positive outlook for the above variables.