Regional Intergration and Migration: An Economic Geography Model with Hetergenous Labour Force

This paper aims to analyse the effect of deepening regional integration on the incentive for factors of production, in particular labour, to spatially relocate. We adopt a general equilibrium, economic-geography model built on Krugman (1991) allowing for skill heterogeneity in the manufacturing sector. At a given level of trade costs, due to the productivity premium associated with the concentration of high-skilled workers in one region, this type of worker will be more willing to migrate than low-skilled ones. The paper shows the existence of a range of trade costs for which only high-skilled workers have an incentive to migrate. Therefore, introducing labour heterogeneity in the basic core-periphery model enables us to explain one of the most striking features of interregional migration patterns: the positive self-selection of the migrants.

Percolation in high dimensions is not understood

The number of spanning clusters in four to nine dimensions does not fully follow the expected size dependence for random percolation.Comment: 9-dimensional data and more points for large lattices added; statistics improved, text expanded, table of exponents inserte

On the importance of openness for industrial policy design in developing countries

Should industrial policy be targeted to a few sectors or be more broad based and therefore more neutral? Our theoretical analysis demonstrates that access to foreign markets is key to answering this question. We show that in a less open economy, industrial policy should be targeted, while in a more open economy, broad based policies are likely to be more effective. One implication of this results is that deregulation is likely to be more successful in a relatively open economy than in a more closed economy. Indeed, deregulation with limited foreign market access may lead to deindustrialization. We provide empirical results that support these predictions.Industrialization, policy design, policy reform, economic growth, openess

Human Capital Accumulation and Migration in a Peripheral EU Region: the Case of Basilicata

The importance of human capital as a key source of value added, innovation and economic growth is widely acknowledged by both economists and policy-makers. Local governments can directly affect individuals’ decision making by subsidising human capital formation. The ability of a regional system to generate human capital is crucial but it is not a sufficient condition leading to economic success. In this work we emphasise the importance of maintaining and attracting high-skilled individuals, and the challenge that migration flows pose on policymaking aimed at fostering human capital accumulation. Human capital does not always benefits the region where it was funded and the scope for the policy might vanish if the human capital formed locally is lost through migration, as emphasised by the “brain drain” literature. When agglomeration forces are at work, human capital migrates from where it is scarce to where it is abundant, rather than vice versa (Lucas 1988). This can result in migration widening the regional wage and income gap and lowering the standard of living in the peripheral location. Poor regions lose through migration their most valuable residents, the main source of innovation and productivity in a modern economy. This phenomenon contributes in explaining the persistent nature of regional economic imbalances. These consideration are highlighted through the analysis of a case study, the migration decision of a sample of highly educated and skilled individuals residing in a small peripheral Mezzogiorno region (Basilicata) which have benefited from a locally funded human capital investment policy. The regional policymakers, in recognition of the importance of human capital as a key ingredient for regional growth, have given generous subsidies since the beginning of the 90s to young graduates who wanted to attend a post-graduate course outside or inside the region. More than a thousand individuals have benefited from the policy in the last decade, and the target for the period 2000-2006 is to subsidise an additional two thousand individuals. A dataset was generated through a survey questionnaire which aims at directly asking people about their decision whether or not to move and the main factors influencing their decision. For each individual, we have collected data on background, experience and outcome of higher education, opinion on the quality of the course attended, job-search strategy after the course, and space-time career details from the first employment to the current employment status. The policy intervention under scrutiny and in particular the biased nature of the sample (highly skilled and educated individuals) makes the analysis a natural experiment for assessing the ability of the regional system in a peripheral EU region not only to generate human capital but also to maintain it. The focus of the paper is on the micro level migratory behaviour. In particular, we want to shed light on the following questions: (1) Who are the migrants; (2) What are the main factors influencing migration; (3) What is the resulting “geography” of the human capital generated? Is the human capital attracted toward core regions?

Relaxation properties in a lattice gas model with asymmetrical particles

We study the relaxation process in a two-dimensional lattice gas model, where the interactions come from the excluded volume. In this model particles have three arms with an asymmetrical shape, which results in geometrical frustration that inhibits full packing. A dynamical crossover is found at the arm percolation of the particles, from a dynamical behavior characterized by a single step relaxation above the transition, to a two-step decay below it. Relaxation functions of the self-part of density fluctuations are well fitted by a stretched exponential form, with a $\beta$ exponent decreasing when the temperature is lowered until the percolation transition is reached, and constant below it. The structural arrest of the model seems to happen only at the maximum density of the model, where both the inverse diffusivity and the relaxation time of density fluctuations diverge with a power law. The dynamical non linear susceptibility, defined as the fluctuations of the self-overlap autocorrelation, exhibits a peak at some characteristic time, which seems to diverge at the maximum density as well.Comment: 7 pages and 9 figure

Intentions to Return of Irregular Migrants: Illegality as a Cause of Skill Waste

In this paper we show that highly skilled illegal migrants may be more likely to return home than migrants with low or no skills when illegality causes skill waste, i.e. reduced ability of making use of individual capabilities both in the labor and the financial markets. This result is in contrast with common wisdom on return migration, according to which low-skill individuals are more likely to go back home rather than high-skill migrants. The simple theoretical life-cycle framework that shows the former result is tested on a sample of illegal migrants crossing Italian borders in 2003. The estimation results confirm that highly skilled illegal migrants are more willing to return home.Illegal migration, labor skills, skill waste.

Number of spanning clusters at the high-dimensional percolation thresholds

A scaling theory is used to derive the dependence of the average number of spanning clusters at threshold on the lattice size L. This number should become independent of L for dimensions d<6, and vary as log L at d=6. The predictions for d>6 depend on the boundary conditions, and the results there may vary between L^{d-6} and L^0. While simulations in six dimensions are consistent with this prediction (after including corrections of order loglog L), in five dimensions the average number of spanning clusters still increases as log L even up to L = 201. However, the histogram P(k) of the spanning cluster multiplicity does scale as a function of kX(L), with X(L)=1+const/L, indicating that for sufficiently large L the average will approach a finite value: a fit of the 5D multiplicity data with a constant plus a simple linear correction to scaling reproduces the data very well. Numerical simulations for d>6 and for d=4 are also presented.Comment: 8 pages, 11 figures. Final version to appear on Physical Review

Sharing and cooperation in an experiment with heterogeneous groups

We investigate the impact of inequality on sharing and cooperation using a dictator game and a linear public good game where some participants work for their endowment (“workers”) while others do not (“non-workers”). Moreover, we differentiate between two types of inequality, namely in source and in level. In contrast to most studies, participants are fully informed about the endowment of the other players. The key finding of our paper is that both sharing and cooperation critically depend on the source of the endowment. In particular, workers are more likely to share with other workers than with non-workers and more inclined to contribute to the public good when grouped with other workers rather than when grouped with non-workers. Considering also the choices made by non-workers, we argue that the worker premium in sharing and cooperation is based on fairness considerations rather than an in-group bias. Adding inequality in the level of endowment reduces the importance of the source of endowment as driver of behavior. This also suggests that reducing one layer of inequality may not improve cooperative behavior in society significantly, implying that a big-push policy tackling many dimensions of inequality at the same time may be required.publishedVersio

Percolation and cluster Monte Carlo dynamics for spin models

A general scheme for devising efficient cluster dynamics proposed in a previous letter [Phys.Rev.Lett. 72, 1541 (1994)] is extensively discussed. In particular the strong connection among equilibrium properties of clusters and dynamic properties as the correlation time for magnetization is emphasized. The general scheme is applied to a number of frustrated spin model and the results discussed.Comment: 17 pages LaTeX + 16 figures; will appear in Phys. Rev.