Migration modeling: an extension of gravity model

We consider an extension of the gravity model of migration taking into account attracting and intermediate factors. Our model is based on the experimental analysis of legal migration and factors influencing its intensity. A rule of destination country selection by migrants is formulated. We propose a novel index of administrative regime which reflects how favorable the migration law and regulations are in the given country. The model parameters are estimated from statistical data. The ethnic heterogeneity of former USSR countries was estimated from 2009-2014 years data.