spatial modeling

Following the intensification of inequality in regions and its harmful effects such as irregular migration and evacuation of some regions, the government and parliament during 1990 onwards various structures in the five-year development plan and budget laws such as revenue-expenditure system, regional balance credits, two percent of the revenue from the sale of crude oil, etc. is intended to reduce the above inequality and create a balance between the regions of the country. Despite the passage of about twenty years of designing and compiling these structures, the results and the effectiveness of these measures have not been examined. Therefore, while identifying regional inequalities and their factors, it is necessary to examine the effects of the implementation of fiscal policies implemented over the past twenty years on regional inequality. This study seeks to examine the factors affecting regional inequality and identify the impact of specific government budget policies designed to reduce regional inequalities and implemented since the beginning of the Third Development Plan on regional inequality. For this purpose, statistics related to 31 provinces during the years 1990 in the form of spatial econometric model has been used. The results of the Spatial Durbin Model (SDM) indicate that the fiscal policies implemented over the past twenty years to reduce regional inequality have not had a significant impact on regional inequality. Therefore, it cannot be hoped that the continuation of this structure in the future can reduce inequality between regions. Changing this variable in a province not only has no significant effect on the inequality of that province but also has no significant effect on the inequality of other provinces. Therefore, this policy, have not had a significant effect in recent years and it is necessary to reconsider this policy.

Small and medium industries are some of the most important economic sectors in any country. These industries, usually transforming to business incubator by economies of agglomeration in industrial centers, while large industries are becoming growth poles based on economies of scale. In the regional economics framework, SMEs affect the geographic space and large industries affect the economic space. While small industries by relying on the diffusion effects play their role in industrial development and economic growth as a business incubator. The present article is examining and modeling two issues in the field of small and medium industries’ activities effects: the diffusion process modeling and the modeling of how information transmission (or similarly, technology and innovation). Both issues can be brought up in the wave theories. Among two given regions, differences between the type and function of industries can usually make the difference between the waves. considering that each industry has its own preceding and following effects, each region also proportion to the type of established industries in it can have preceding and following effects on the other regions in geographic space and economic space. For the diffusion process model, the approach of gravity model, and for the process pattern and how information transmission, a hierarchical system is used. In both methods, the results are shown in form of the diffusion models in general and under specific conditions. The extracted theoretical functions indicate how the regions interact based on the types of established industries in them. The effects of the considered models show that the SMEs can have significant effects on the surrounding regions around via sending permanent innovation waves, information, and other development waves.