44,182 research outputs found
Income taxes as reciprocal tariffs
This article shows the equivalence between tariffs on international trade and income taxation. Traditionally, income taxes have been seen as lowering society's output through the household's labor-leisure trade-off. Income taxes also reduce the degree to which individuals specialize in market activity, which is similar to the way countries respond to tariffs in international trade. Income taxes discourage individuals from specializing in activities that reflect their comparative advantage. In so doing, income taxes may have their most distorting effects, not by encouraging individuals to work less but by causing them to spend more time working at endeavors for which their talent is limited. Using a general model of interpersonal exchange, the authors demonstrate parallels between income taxes and tariffs. Over a range of income taxes, raising taxes can benefit large groups of similarly skilled individuals and hurt small groups. As in tariff theory, the costs of income taxes are small only if they succeed in raising revenue. Thus, it is very costly for an economy to be on the downward portion of its tax revenue (Laffer) curve. The more heterogeneous the society, the higher the income tax rate that will maximize tax revenues. By overlooking the effects of heterogeneity in the workforce and the potential for workers to flee to home production, policymakers may under- or overestimate the effects of income taxes on various sectors of the economy and tax with unintended consequences.Income tax ; Tariff ; Taxation
3D MHD Modeling of the Gaseous Structure of the Galaxy: Synthetic Observations
We generated synthetic observations from the four-arm model presented in
Gomez & Cox (2004) for the Galactic ISM in the presence of a spiral
gravitational perturbation. We found that velocity crowding and diffusion have
a strong effect in the l-v diagram. The v-b diagram presents structures at the
expected spiral arm velocities, that can be explained by the off-the-plane
structure of the arms presented in previous papers of this series. Such
structures are observed in the Leiden/Dwingeloo HI survey. The rotation curve,
as measured from the inside of the modeled galaxy, shows similarities with the
observed one for the Milky Way Galaxy, although it has large deviations from
the smooth circular rotation corresponding to the background potential. The
magnetic field inferred from a synthetic synchrotron map shows a largely
circular structure, but with interesting deviations in the midplane due to
distortion of the field from circularity in the interarm regions.Comment: Accepted for publication in ApJ. Better quality figures in
http://www.astro.umd.edu/~gomez/publica/3d_galaxy-3.pd
Agenda Control in the Bundestag, 1980-2002
We find strong evidence of monopoly legislative agenda control by government parties in the Bundestag. First, the government parties have near-zero roll rates, while the opposition parties are often rolled over half the time. Second, only opposition parties’ (and not government parties’) roll rates increase with the distances of each party from the floor median. Third, almost all policy moves are towards the government coalition (the only exceptions occur during periods of divided government). Fourth, roll rates for government parties sky- rocket when they fall into the opposition and roll rates for opposition parties plummet when they enter government, while policy movements go from being nearly 100 per cent rightward when there is a rightist government to 100 per cent leftward under a leftist government
Simulation of stellar instabilities with vastly different timescales using domain decomposition
Strange mode instabilities in the envelopes of massive stars lead to shock
waves, which can oscillate on a much shorter timescale than that associated
with the primary instability. The phenomenon is studied by direct numerical
simulation using a, with respect to time, implicit Lagrangian scheme, which
allows for the variation by several orders of magnitude of the dependent
variables. The timestep for the simulation of the system is reduced appreciably
by the shock oscillations and prevents its long term study. A procedure based
on domain decomposition is proposed to surmount the difficulty of vastly
different timescales in various regions of the stellar envelope and thus to
enable the desired long term simulations. Criteria for domain decomposition are
derived and the proper treatment of the resulting inner boundaries is
discussed. Tests of the approach are presented and its viability is
demonstrated by application to a model for the star P Cygni. In this
investigation primarily the feasibility of domain decomposition for the problem
considered is studied. We intend to use the results as the basis of an
extension to two dimensional simulations.Comment: 15 pages, 10 figures, published in MNRA
Adaptation Reduces Variability of the Neuronal Population Code
Sequences of events in noise-driven excitable systems with slow variables
often show serial correlations among their intervals of events. Here, we employ
a master equation for general non-renewal processes to calculate the interval
and count statistics of superimposed processes governed by a slow adaptation
variable. For an ensemble of spike-frequency adapting neurons this results in
the regularization of the population activity and an enhanced post-synaptic
signal decoding. We confirm our theoretical results in a population of cortical
neurons.Comment: 4 pages, 2 figure
Surface versus bulk characterization of the electronic inhomogeneity in a VO_{2} film
We investigated the inhomogeneous electronic properties at the surface and
interior of VO_{2} thin films that exhibit a strong first-order metal-insulator
transition (MIT). Using the crystal structural change that accompanies a VO_{2}
MIT, we used bulk-sensitive X-ray diffraction (XRD) measurements to estimate
the fraction of metallic volume p^{XRD} in our VO_{2} film. The temperature
dependence of the p was very closely correlated with the dc
conductivity near the MIT temperature, and fit the percolation theory
predictions quite well: (p - p_{c})^{t} with t = 2.00.1
and p_{c} = 0.160.01. This agreement demonstrates that in our VO
thin film, the MIT should occur during the percolation process. We also used
surface-sensitive scanning tunneling spectroscopy (STS) to investigate the
microscopic evolution of the MIT near the surface. Similar to the XRD results,
STS maps revealed a systematic decrease in the metallic phase as temperature
decreased. However, this rate of change was much slower than the rate observed
with XRD, indicating that the electronic inhomogeneity near the surface differs
greatly from that inside the film. We investigated several possible origins of
this discrepancy, and postulated that the variety in the strain states near the
surface plays an important role in the broad MIT observed using STS. We also
explored the possible involvement of such strain effects in other correlated
electron oxide systems with strong electron-lattice interactions.Comment: 27 pages and 7 figure
Multiple Molecular H2 Outflows in AFGL 618
We report high spatial (0.5 arcsec) and high spectral (9 km/s) resolution
spectro-imaging of the 2.12 micron H2 1-0 S(1) line in the proto-planetary
nebula AFGL 618 using BEAR at the CFHT. The observations reveal the presence of
multiple, high-velocity, molecular outflows that align with the remarkable
optical jets seen in HST images. The structure and kinematics of the outflows
show how jets interact with circumstellar gas and shape the environment in
which planetary nebulae form.Comment: 14 pages, 5 figures. To appear in The Astrophysical Journal Letter
The Nikolaevskiy equation with dispersion
The Nikolaevskiy equation was originally proposed as a model for seismic
waves and is also a model for a wide variety of systems incorporating a
neutral, Goldstone mode, including electroconvection and reaction-diffusion
systems. It is known to exhibit chaotic dynamics at the onset of pattern
formation, at least when the dispersive terms in the equation are suppressed,
as is commonly the practice in previous analyses. In this paper, the effects of
reinstating the dispersive terms are examined. It is shown that such terms can
stabilise some of the spatially periodic traveling waves; this allows us to
study the loss of stability and transition to chaos of the waves. The secondary
stability diagram (Busse balloon) for the traveling waves can be remarkably
complicated.Comment: 24 pages; accepted for publication in Phys. Rev.
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