Abian Garcia-Rodriguez (p), Edgar Morgenroth (p)

Internal migration contributes to changes in the geographic distribution of the population. Various factors explaining the level and pattern of internal migration have been investigated in the literature. However, in much of the existing literature the actual destination of a migrant is taken as their preferred destination. However, as migrants face a budget constraint particularly regarding housing they might locate in neighbouring areas to their preferred area. This implies that house prices and other variables such as those relating to the labour market in neighbouring regions to the destination are important in determining the spatial pattern of internal migration. Furthermore, housing bubbles and busts apart from affecting migration rates will also have an impact on the spatial patterns of migration. This paper investigates the impact of housing cycles on internal migration in Ireland. In the wake of the so called ‘Celtic Tiger’ boom, Ireland experienced a significant housing bubble which ended in a dramatic collapse. Over this period net internal migration patterns across Irish counties, which had been quite stable changed significantly, so much so that the correlation between the patterns observed in 1996 and 2002 is -0.57. In the wake of the bursting of the housing bubble internal migration patterns have changed again with the correlation of county internal net-migration between 2006 and 2011 of -0.09. The analysis in this paper is conducted at the county level over the period 1996 to 2016, which encompasses the pre boom, boom, crash and recovery period.

Ngoc Thi Minh Tran (p), Michael P. Cameron, Jacques Poot

International migrants are widely known as agents of institutional change in their home countries. However, the huge growth in temporary migration in recent years demands a fresh investigation of this phenomenon. Theoretically, a country’s diaspora constitutes one of the four principal channels through which international migration may alter development. A core factor enabling the transnational influence of diasporas is their retained connection to home countries, which is plausibly contingent on the duration-of-stay in the host countries. This paper exploits the Database on Immigrants in OECD Countries (DIOC) to investigate the influence of diasporas living in OECD countries on institutional quality in home countries and takes into account the heterogeneity of diasporas’ duration-of-stay composition. Instead of simply using immigrant numbers to measure the diaspora size, we calculate institutional-quality-adjusted immigrant stocks to allow for the variation in institutional quality in host countries. Additionally, we utilize duration-of-stay in the host country as an indicator of the strength of interaction with the home country. Our cross-sectional and panel analyses find a significant positive impact of diasporas living in OECD countries on institutional quality in home countries. Remarkably, the diffusion of advanced institutions from developed host countries to home countries through the international migration channel is stronger with diasporas characterized by shorter duration-of-stay, i.e. with those who may be expected to still have stronger links with the home country.

Renato Guedes (p), José Martins, Eduardo Castro, João Marques

In order to estimate the migrant population by age group and sex in the regional context of Portugal, we developed a model linking the economic growth with the flow of migrant population. This model estimates, by ordinary least squares (OLS), the net migration of each combination of sex and age group as a function of the following variables: the balance between supply and demand of employment in the primary and secondary sectors; per capita GDP; demographic potential; and net migration in the past for lagged age groups (migration for age x-n, n years ago), in order to represent the phenomenon of elderly people return to the place of origin. Each of 28 estimates (age group from 15 years old onwards) are independent from each other. The number of migrants younger than 15 years old is related to mothers’ migration flows.
The main weakness of the model arises from the high number of parameters in contrast to the number of degrees of freedom. This problem can be overcome by the use of Bayesian statistics, incorporating spatial auto-correlated random effects, in combination with a Markov chain Monte Carlo (MCMC) algorithm. This provides additional advantages:
1. The description of the parameters as posterior distributions, instead of point estimates, provide flexibility to make statistical inference as well as richer information.
2. As we intend to add further explanatory variables and to make estimates for smaller regions, the problems arising from missing or low quality data will became more frequent. The use of auto-correlation effects will partially overcome such weaknesses by correcting local data, which borrow strength from the neighbourhood.
3. Right now, the model estimates the migration of children as a function of the women migration (mothers) assuming fertility rates equal to those of host regions, what is not an accurate procedure. By using a hierarchical Bayesian multivariate regression model to simultaneously infer the complete set of migration flows, we can circumvent such a problem.
The presentation of the hierarchical Bayesian migration model and of forecasts for Portugal are the main objectives of our presentation.

Gabriel Oliveira (p), André Chagas

In this paper we estimated the effect of cash transfers on migration flows among brazilian municipalities from 2008 to 2010, calculated with the Demographic Census of 2010. We consider the cash transfer program named Bolsa Família (PBF), and aggregate origin-destination flows with spatial dependence equations in a Discrete Choice Model.
To develop our analysis, the individuals are separated into six per capita family income profiles. In face of the PBF aim, we focus on the first four profiles. Then, some mechanisms that can influence the decision to migrate or to stay in the same municipality are suggested. Each mechanism differs according to the individual status, of being a beneficiary of the program or not, according to his income profile, and also according to the analysed feature of the program being about his own municipality, or of another one for where he can migrate.
As robustness, we estimated a Logit model of the individual likelihood of having migrated, given his characteristics, among which being beneficiary, and given the characteristics of his origin municipality, among which the PBF management features. We also report estimates with the flows between 1995 and 2000 and the different conclusions, as expected.
The results seem to replicate the main finds of migration literature, and point to the relevance of being concerned with the management of the program and the release of resources, because of its influences on individual location decision.