Commodity Price Shocks and the Business Cycle: Structural Evidence for the U.S.

This paper develops a 9-dimensional SVAR to investigate the sources of the U.S. business cycle. We extend the standard set of identified shocks to include unexpected changes in commodity prices. Our main result is that commodity price shocks are a very important driving force of macroeconomic fluctuations, second only to investment-specific technology shocks. In particular, we find that commodity price shocks explain a large share of cyclical movements in inflation. Neutral technology shocks and monetary policy shocks seem less relevant at business cycle frequencies. The impulse response dynamics provide support for medium-scale DSGE models, but not for strong price rigidities.business cycles, commodity price shocks, structural VAR

Commodity Price Shocks and the Business Cycle: Structural Evidence for the U.S.

This paper develops a 9-dimensional SVAR to investigate the sources of the U.S. business cycle. We extend the standard set of identified shocks to include unexpected changes in commodity prices. Our main result is that commodity price shocks are a very important driving force of macroeconomic fluctuations, second only to investment-specific technology shocks. In particular, we find that commodity price shocks explain a large share of cyclical movements in inflation. Neutral technology shocks and monetary policy shocks seem less relevant at business cycle frequencies. The impulse response dynamics provide support for medium-scale DSGE models, but not for strong price rigidities.business cycles, commodity price shocks, structural VAR

Strategic Wage Bargaining, Labor Market Volatility, and Persistence

This paper modifies the standard Mortensen-Pissarides model in order to explain the cyclical behavior of vacancies and unemployment. The modifications include strategic wage bargaining and convex labor adjustment costs. We find that this setup replicates the cyclical behavior of both labor market variables remarkably well. First, we show that the model with strategic wage bargaining matches closely the volatility of vacancies and unemployment. Second, the introduction of convex labor adjustment costs makes both variables much more persistent. Third, our analysis indicates that these two modifications are complementary in generating labor market volatility and persistence.Business Cycles, Matching, Strategic Bargaining, Vacancy Persistence

Shocks and Frictions under Right-to-Manage Wage Bargaining: A Transatlantic Perspective

Business Cycles, Labor Market Search, Wage Bargaining, Inflation

Calculation and spectroscopy of the Landau band structure at a thin and atomically precise tunneling barrier

Two laterally adjacent quantum Hall systems separated by an extended barrier of a thickness on the order of the magnetic length possess a complex Landau band structure in the vicinity of the line junction. The energy dispersion is obtained from an exact quantum-mechanical calculation of the single electron eigenstates for the coupled system by representing the wave functions as a superposition of parabolic cylinder functions. For orbit centers approaching the barrier, the separation of two subsequent Landau levels is reduced from the cyclotron energy to gaps which are much smaller. The position of the anticrossings increases on the scale of the cyclotron energy as the magnetic field is raised. In order to experimentally investigate a particular gap at different field strengths but under constant filling factor, a GaAs/AlGaAs heterostructure with a 52 Angstrom thick tunneling barrier and a gate electrode for inducing the two-dimensional electron systems was fabricated by the cleaved edge overgrowth method. The shift of the gaps is observed as a displacement of the conductance peaks on the scale of the filling factor. Besides this effect, which is explained within the picture of Landau level mixing for an ideal barrier, we report on signatures of quantum interferences at imperfections of the barrier which act as tunneling centers. The main features of the recent experiment of Yang, Kang et al. are reproduced and discussed for different gate voltages. Quasiperiodic oscillations, similar to the Aharonov Bohm effect at the quenched peak, are revealed for low magnetic fields before the onset of the regular conductance peaks.Comment: 8 pages, 10 figures, 1 tabl

Familial hemiplegic migraine with cerebellar ataxia and paroxysmal psychosis

Familial hemiplegic migraine is a rare autosomal dominant disorder associated with stereotypic neurologic au ra phenomena including hemiparesis, So far two chromosomal loci have been identified. Families linked to the chromosome 19 locus display missense mutations within the CACNL1A4 gene. Here we report on a family with familial hemiplegic migraine and cerebellar ataxia with recurrent episodes of acute paranoid psychosis with anxiety and visual hallucinations associated with migraine attacks. Based on the clinical and haplotype evidence indicating linkage to chromosome 19 in this family, we hypothesize that a dysfunction of the mutated calcium channel may be involved not only in the development of hemiplegic migraine but also in the acute psychotic episodes observed in these patients