Why Do People Move? Modern Gravity Model of Inter-Provincial Migration in Iran 2011-2016

Internal migration is a mechanisms to adjustment with regional socioeconomic differences and an important basis for planning, but received less attention in demographic literature. Migration is affected by a complex factors of determination that requires some powerful tools to investigating. Gravity model is one of the most important tools that examines these factors with two pure and generalized approaches. The purpose of this article is investigating these factors in Iran based on this model. The required data include the number of inter-provincial migrations and socio-economic variables obtained from the 2016 census of the Statistics Center of Iran and selected based on previous studies. The results showed that the pure gravity model can explain 69% of inter-provincial migration, while in the generalized model this reached 91%. In general, the social network factor and then the distance have the greatest impact on regional migration. Analysis of the effect of push and pull factors showed that push factors are able to explain 53% and pull factors 39% of the migration volume between the two provinces. Therefore, according to the gravity model of inter-provincial migration in Iran, the role of push factors is more than pull factors. As a result, the only way to moderate inter-regional migration would be to create services and facilities for less developed regions and reduce regional differences.