Zipf’s and Gibrat’s laws for migrations (original) (raw)
Related papers
On the Economic Geography of International Migration
The World Economy, 2015
On the Economic Geography of International Migration * We exploit the bilateral and skill dimensions from recent data sets of international migration to test for the existence of Zipf's and Gibrat's Laws in the context of aggregate and highskilled international immigration and emigration using graphical, parametric and nonparametric analysis. The top tails of the distributions of aggregate and high-skilled immigrants and emigrants adhere to a Pareto distribution with an exponent of unity i.e. Zipf's Law holds. We find some evidence in favour of Gibrat's Law holding for immigration stocks, i.e. that the growth in stocks is independent of their initial values and stronger evidence that immigration densities are diverging over time. Conversely, emigrant stocks are converging in the sense that countries with smaller emigrant stocks are growing faster than their larger sovereign counterparts. Lastly, high skilled immigration and emigration stocks expressed in levels or as densities all exhibit signs of convergence. We conclude by discussing some competing mechanisms that could be driving the observed patterns including: differing fertility rates, reductions in emigration restrictions, migrant sorting and selective immigration policies, immigrant networks and persisting wage differentials.
Estimation of Internal Migration by the National Growth Rate Method: An Alternative Approach
Bangladesh Development Studies
This paper proposes an extension of the National Growth Rate Method (NGRM) for making flexible estimation of internal migration into a region or a city, by incorporating the migration pattern as a function of time. Several single-and two-parameter families of functions of time have been suggested for the purpose. The estimation procedure is outlined along with the data requirement. The flexible NGRM, like its precursor of improved NGRM, can provide separate estimates for both the net migrants and their natural increase, which can be subjected to socioeconomic analysis for the motivations or implications of migration.
Size and resources driven migration resulting in a power-law distribution of cities
Physica A: Statistical Mechanics and its Applications, 2005
In this paper, we present a model for the distribution of individuals in cities. The number of individuals is fixed and the dynamic depends on migration from one city to another. Individuals migrate in order to pursue their well-being which in turn is obtained with two strategies: utilisation of resources for production and selling of products to people. Because resources are uniformly distributed and shared among individuals, the first strategy pushes individuals in small cities. In turn, because selling depends on the quantity of individuals are living in a city, the second strategy pushes individuals in big cities. According to Zipf, these strategies are called unification and diversification and their random application results in power-law distribution of cities. This distribution is studied in two regions: the first ranges from a minimum size to the size whose frequency is equal to one, the second from this size to the maximum admitted size. The numerical results of the main variables are discussed, and relations with similar models are shown.
Migration dynamics, growth and convergence
Journal of Economic Dynamics and Control, 2006
The aim of the present paper is to analyze the impact of migration dynamics on economic growth and convergence in terms of both the capital/labor ratio and wages. From our results, the following main conclusions can be highlighted: 1) migration positively affects the sending country because of the improvement in the capital/labor ratio and the savings of returning workers; 2) the differences existing between countries do not necessarily disappear in the long term, so the convergence that arises is limited or conditional because it does not necessarily imply an equalization of per capita income, capital/labor ratio, and wages, or the disappearance of migration; and 3) the possibility of migratory flow reversion cannot be excluded in the transitory dynamics.
Estimating changes of residence for cross-national comparison
2012
This paper considers a number of temporal and spatial models that can be used for international comparison of internal migration levels across all countries of the world. First, among the various spatial models used, the model linking migrations to the zoning of the territory provides a simple summary of this relationship, but its parameters do not have a clear plain language meaning for international comparison. Second, the “migrant-migration” model derives an instantaneous rate based on migrant numbers measured over variable durations that is independent of multiple and return moves occurring over a longer interval. International comparison is thus only possible for the instantaneous mobility rate (change of residence), a standard indicator whose meaning is clear. The authors use numerous examples to show that the simultaneous use of both types of models provides a means, under certain conditions, to approximate such a rate that can be linked to the parameters of these models. The validity of these models can be tested and confirmed using data from countries where direct measures of changes of residence are available.
Canadian Journal of Agricultural Economics/Revue canadienne d'agroeconomie, 1968
The factors influencing migration can, in the most aggregative form, be grouped into pecuniary and nonpecuniary ones. Thus we have three variables which are defined as follows:
The Demographical Aspects of Migration
Analele Stiintifice ale Universitatii" Alexandru Ioan …, 2008
Les problèmes démographiques et migratoires sont étroitement dépendants : les mouvements des populations influence dans le même temps les faits économiques et les structures sociales, soit dans les pays de départ soit dans les pays d"arrivée. Les coûts des migrations sont encore difficiles à estimer.
AN EMPIRICAL TEST OF INCOME DISTRIBUTION AND MIGRATION RELATIONSHIP: A CASE OF TURKEY 1
2014
an important phenomena. There are two types of migration: internal (in migration) and external (out migration). Both of them are because of politic, economic and social reasons. Here both of them are considered inside Turkey. Data is chosen from 2008-2012 periods for the 12 statistically divided regions in Turkey. Following the Panel unit root test, panel least square methods is used for the empirical part. As to result, it is concluded that for the 2008-2012 periods, migration has an adjusting role for 12 statistical regions in Turkey.