149 research outputs found
Highly-educated immigrants and native occupational choice
Economic debate about the consequences of immigration in the US has largely focused on how influxes of foreign-born labor with little educational attainment have affected similarly-educated native-born workers. Fewer studies analyze the effect of immigration within the market for highly-educated labor. We use O*NET data on job characteristics to assess whether native-born workers with graduate degrees respond to an increased presence of highly-educated foreign-born workers by choosing new occupations with different skill content. We find that immigrants with graduate degrees specialize in occupations demanding quantitative and analytical skills, whereas their native-born counterparts specialize in occupations requiring
interactive and communication skills. When the foreign-born proportion of highly educated employment within an occupation rises, native employees with graduate degrees choose new occupations with less analytical and more communicative content. For completeness, we also assess whether immigration causes highly educated natives to lose their jobs or move across state boundaries. We find no
evidence that either occurs
Task specialization, immigration, and wages
Many workers with low levels of educational attainment immigrated to the United States in recent decades. Large inflows of less-educated immigrants would reduce
wages paid to comparably-educated native-born workers if the two groups are perfectly substitutable in production. In a simple model exploiting comparative advantage, however, we show that if less-educated foreign and native-born workers
specialize in performing different tasks, immigration will cause natives to reallocate their task supply, thereby reducing downward wage pressure. We merge occupational task-intensity data from the O*NET and DOT datasets with individual Census data across US states from 1960-2000 to demonstrate that foreign-born workers specialize in occupations that require manual and physical labor skills while natives pursue jobs more intensive in communication and language tasks. Immigration induces natives to specialize accordingly. Simulations show that this
increased specialization might explain why economic analyses commonly find only modest wage and employment consequences of immigration for less-educated native-born workers across U.S. states. This is especially true in states with large
immigration flows
On the Long Time Behavior of the Quantum Fokker-Planck equation
We analyze the long time behavior of transport equations for a class of
dissipative quantum systems with Fokker-planck type scattering operator,
subject to confining potentials of harmonic oscillator type. We establish the
conditions under which there exists a thermal equilibrium state and prove
exponential decay towards it, using (classical) entropy-methods. Additionally,
we give precise dispersion estimates in the cases were no equilibrium state
exists
Semiclassical Asymptotics for the Maxwell - Dirac System
We study the coupled system of Maxwell and Dirac equations from a
semiclassical point of view. A rigorous nonlinear WKB-analysis, locally in
time, for solutions of (critical) order is performed,
where the small semiclassical parameter denotes the
microscopic/macroscopic scale ratio
Classical limit for semi-relativistic Hartree systems
We consider the three-dimensional semi-relativistic Hartree model for fast
quantum mechanical particles moving in a self-consistent field. Under
appropriate assumptions on the initial density matrix as a (fully) mixed
quantum state we prove, using Wigner transformation techniques, that its
classical limit yields the well known relativistic Vlasov-Poisson system. The
result holds for the case of attractive and repulsive mean-field interaction,
with an additional size constraint in the attractive case.Comment: 10 page
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