1,916 research outputs found
The asymmetric unemployment response of natives and foreigners to migration shocks
This paper provides new evidence on the macroeconomic effects of net migration shocks in Germany. Using monthly data from 2006 to 2019 and a variety of identification strategies in a structural vector autoregressive model, we show that migration shocks are expansionary. Net migration increases persistently industrial
production, per capita net exports and tax revenue. In the labor market, migration boosts persistently job openings and, after a year and a half, hourly wages in manufacturing. Total unemployment declines but the response is asymmetric between natives and foreigners. Unemployment falls persistently for natives while it
rises a year after the shock for foreigners as the newly settled migrants enter the labor market gradually. Using also quarterly data in a mixed-frequency SVAR, we shed light on the employment and participation responses for natives and foreigners. We also show that migration shocks increase per capita GDP, investment, and
hourly wages of the aggregate economy. Taken together, our results highlight a job-creation effect for natives and a job-competition effect for foreigners
Simulations of the Microwave Sky and of its ``Observations''
Here follows a preliminary report on the construction of fake millimeter and
sub-millimeter skies, as observed by virtual instruments, e.g. the COBRA/SAMBA
mission, using theoretical modeling and data extrapolations. Our goal is to
create maps as realistic as possible of the relevant physical contributions
which may contribute to the detected signals. This astrophysical modeling is
followed by simulations of the measurement process itself by a given
instrumental configuration. This will enable a precise determination of what
can and cannot be achieved with a particular experimental configuration, and
provide a feedback on how to improve the overall design. It is a key step on
the way to define procedures for the separation of the different physical
processes in the future observed maps. Note that this tool will also prove
useful in preparing and analyzing current (\eg\ balloon borne) Microwave
Background experiments. Keywords: Cosmology -- Microwave Background
Anisotropies.Comment: 6 pages of uuencoded compressed postscript (1.2 Mb uncompressed), to
appear in the proceedings of the meeting "Far Infrared and Sub-millimeter
Space Missions in the Next Decade'', Paris, France, Eds. M. Sauvage, Space
Science Revie
Nonlinear Transmission of Financial Shocks: Some New Evidence
Financial shocks generate a protracted and quantitatively important effect on real economic activity and financial markets only if the shocks are both negative and large. Otherwise, their role is quite modest. Financial shocks have become more important for economic fluctuations after 2000 and have contributed substantially to deepening the recessions of 2001 and 2008. The evidence is obtained using a new econometric procedure based on a Vector Moving Average representation that includes a nonlinear function of the financial shock. This method is a contribution of the present work
Simulations for single-dish intensity mapping experiments
HI intensity mapping is an emerging tool to probe dark energy. Observations
of the redshifted HI signal will be contaminated by instrumental noise,
atmospheric and Galactic foregrounds. The latter is expected to be four orders
of magnitude brighter than the HI emission we wish to detect. We present a
simulation of single-dish observations including an instrumental noise model
with 1/f and white noise, and sky emission with a diffuse Galactic foreground
and HI emission. We consider two foreground cleaning methods: spectral
parametric fitting and principal component analysis. For a smooth frequency
spectrum of the foreground and instrumental effects, we find that the
parametric fitting method provides residuals that are still contaminated by
foreground and 1/f noise, but the principal component analysis can remove this
contamination down to the thermal noise level. This method is robust for a
range of different models of foreground and noise, and so constitutes a
promising way to recover the HI signal from the data. However, it induces a
leakage of the cosmological signal into the subtracted foreground of around 5%.
The efficiency of the component separation methods depends heavily on the
smoothness of the frequency spectrum of the foreground and the 1/f noise. We
find that as, long as the spectral variations over the band are slow compared
to the channel width, the foreground cleaning method still works.Comment: 14 pages, 12 figures. Submitted to MNRA
HI intensity mapping with FAST
We discuss the detectability of large-scale HI intensity fluctuations using
the FAST telescope. We present forecasts for the accuracy of measuring the
Baryonic Acoustic Oscillations and constraining the properties of dark energy.
The FAST -beam L-band receivers (-- GHz) can provide
constraints on the matter power spectrum and dark energy equation of state
parameters () that are comparable to the BINGO and CHIME
experiments. For one year of integration time we find that the optimal survey
area is . However, observing with larger frequency coverage
at higher redshift (-- GHz) improves the projected errorbars on the
HI power spectrum by more than confidence level. The combined
constraints from FAST, CHIME, BINGO and Planck CMB observations can provide
reliable, stringent constraints on the dark energy equation of state.Comment: 7 pages, 3 figures, submitted to "Frontiers in Radio Astronomy and
FAST Early Sciences Symposium 2015" conference proceedin
Vasomotor symptoms in menopause: a biomarker of cardiovascular disease risk and other chronic diseases?
Menopausal disorders may include shorter-term symptoms, such as hot flushes and night sweats (vasomotor symptoms, VMS) and longer-term chronic conditions such as cardiovascular disease (CVD), osteoporosis, and cognitive impairment. Initially, no clear link between the shorter-term symptoms and longer-term chronic conditions was evident and these disorders seemed to occur independently from each other. However, there is a growing body of evidence demonstrating that VMS may be a biomarker for chronic disease. In this review, the association between VMS and a range of chronic postmenopausal conditions including CVD, osteoporosis, and cognitive decline is discussed. Prevention of CVD in women, as for men, should be started early, and effective management of chronic disease in postmenopausal women has to start with the awareness that VMS during menopause are harbingers of things to come and should be treated accordingly
Fundamental mechanisms of energy exchanges in autonomous measurements based on dispersive qubit-light interaction
Measuring an observable that does not commute with the system's Hamiltonian
usually leads to a variation of its energy. Unveiling the first link of the von
Neumann chain, the quantum meter has to account for this energy change. Here,
we consider an autonomous meter-system dynamics: a qubit interacting
dispersively with a light pulse propagating in a one-dimensional waveguide. The
light pulse (the meter) measures the qubit's state along the -axis while the
qubit's Hamiltonian is oriented along another direction. As the interaction is
dispersive, photon number is conserved so that energy balance has to be
attained by spectral deformations of the light pulse. An accurate and
repeatable measurement can be achieved only by employing short pulses, where
their spectral deformation is practically undetectable. Increasing the pulse's
duration, the measurement's quality drops and the spectral deformation of the
scattered field becomes visible. Building on analytical and numerical
solutions, we reveal the mechanism underlying this spectral deformation and
display how it compensates for the qubit's energy change. We explain the
formation of a three-peak structure of the output spectrum and we provide the
conditions under which this is observable.Comment: 9 pages plus appendices, 9 figure
- …