323 research outputs found
The Public Choice View of International Political Economy
This paper surveys the applications of Public Choice theory (that is, the economic approach to politics) to international political economy. The central characteristics and the main theoretical concepts of this approach are discussed and its applications in various problem areas are described. The advantages and disadvantages of the Public Choice viewpoint compared with the traditional (political-science-based) view of international political economy are evaluated. It is concluded that the former approach represents an interesting and worthwhile complement to the latter
Price indices for artists - A proposal
This paper proposes a price index for artists based on the ratio between the average market price and the average estimated price of the paintings sold by an artist each year, adjusted for market dynamics. We apply this methodology to a group of selected artists and schools drawing from a database including auction prices and estimated prices of paintings presented in auctions world wide between 1990 and 2001. A comparison with quality unadjusted and hedonic indices is also proposed
Presidential Popularity and Reputation
This paper reports on the results of an empirical study of relationships between the popularity of US presidents and economic variables. Traditionally, these relationships are based on the hypothesis that voters hold the incumbent President responsible for the economic situation. We derive an alternative specification of popularity, based on the hypothesis that political parties perform better on different issues. Empirical evidence turns out to be strongly in favour of our hypothesis. Our findings have important implications for studies on government behaviour in which it is assumed that one of the objectives of administrations is to maximise votes
N=2 Super-Higgs, N=1 Poincare' Vacua and Quaternionic Geometry
In the context of N=2 supergravity we explain the occurrence of partial
super-Higgs with vanishing vacuum energy and moduli stabilization in a model
suggested by superstring compactifications on type IIB orientifolds with 3-form
fluxes.
The gauging of axion symmetries of the quaternionic manifold, together with
the use of degenerate symplectic sections for special geometry, are the
essential ingredients of the construction.Comment: 18 page
Government Spending Cycles: Ideological or Opportunistic?
ands. The time series analysis, covering the period 1953â1993, allows for different types of government spending. In general, spending is inspired by ideological and opportunistic motives: all government expenditure categories show an upward drift during election times and the partisan motives behind government spending are clearly revealed: left-wing cabinets attach greater importance to social security and health care than right-wing cabinets and right-wing cabinets value expenditure on infrastructure and defense more than left-wing parties.
Constructive comments by Frans van Winden, Wilko Letterie, Peter Cornelisse, Arie Ros, André de Moor, Harry ter Rele and an anonymous referee are gratefully acknowledged
D-Sitter Space: Causal Structure, Thermodynamics, and Entropy
We study the entropy of concrete de Sitter flux compactifications and
deformations of them containing D-brane domain walls. We determine the relevant
causal and thermodynamic properties of these "D-Sitter" deformations of de
Sitter spacetimes. We find a string scale correspondence point at which the
entropy localized on the D-branes (and measured by probes sent from an observer
in the middle of the bubble) scales the same with large flux quantum numbers as
the entropy of the original de Sitter space, and at which Bousso's bound is
saturated by the D-brane degrees of freedom (up to order one coefficients) for
an infinite range of times. From the geometry of a static patch of D-Sitter
space and from basic relations in flux compactifications, we find support for
the possibility of a low energy open string description of the static patch of
de Sitter space.Comment: 46 pages, harvmac big; 14 figure
Open String Wavefunctions in Warped Compactifications
We analyze the wavefunctions for open strings in warped compactifications,
and compute the warped Kahler potential for the light modes of a probe D-brane.
This analysis not only applies to the dynamics of D-branes in warped
backgrounds, but also allows to deduce warping corrections to the closed string
Kahler metrics via their couplings to open strings. We consider in particular
the spectrum of D7-branes in warped Calabi-Yau orientifolds, which provide a
string theory realizations of the Randall-Sundrum scenario. We find that
certain background fluxes, necessary in the presence of warping, couple to the
fermionic wavefunctions and qualitatively change their behavior. This modified
dependence of the wavefunctions are needed for consistency with supersymmetry,
though it is present in non-supersymmetric vacua as well. We discuss the
deviations of our setup from the RS scenario and, as an application of our
results, compute the warping corrections to Yukawa couplings in a simple model.
Our analysis is performed both with and without the presence of D-brane
world-volume flux, as well as for the case of backgrounds with varying dilaton.Comment: 52 pages, refs. added, minor correction
Age, Health and Life Satisfaction Among Older Europeans
In this paper we investigate how age affects the self-reported level of life satisfaction among the elderly in Europe. By using a vignette approach, we find evidence that age influences life satisfaction through two counterbalancing channels. On the one hand, controlling for the effects of all other variables, the own perceived level of life satisfaction increases with age. On the other hand, given the same true level of life satisfaction, older respondents are more likely to rank themselves as âdissatisfiedâ with their life than younger individuals. Detrimental health conditions and physical limitations play a crucial role in explaining scale biases in the reporting style of older individuals
Axionic D3-D7 Inflation
We study the motion of a D3 brane moving within a Type IIB string vacuum
compactified to 4D on K3 x T_2/Z_2 in the presence of D7 and O7 planes. We work
within the effective 4D supergravity describing how the mobile D3 interacts
with the lightest bulk moduli of the compactification, including the effects of
modulus-stabilizing fluxes. We seek inflationary solutions to the resulting
equations, performing our search numerically in order to avoid resorting to
approximate parameterizations of the low-energy potential. We consider
uplifting from D-terms and from the supersymmetry-breaking effects of anti-D3
branes. We find examples of slow-roll inflation (with anti-brane uplifting)
with the mobile D3 moving along the toroidal directions, falling towards a
D7-O7 stack starting from the antipodal point. The inflaton turns out to be a
linear combination of the brane position and the axionic partner of the K3
volume modulus, and the similarity of the potential along the inflaton
direction with that of racetrack inflation leads to the prediction n_s \le 0.95
for the spectral index. The slow roll is insensitive to most of the features of
the effective superpotential, and requires a one-in-10^4 tuning to ensure that
the torus is close to square in shape. We also consider D-term inflation with
the D3 close to the attractive D7, but find that for a broad (but not
exhaustive) class of parameters the conditions for slow roll tend to
destabilize the bulk moduli. In contrast to the axionic case, the best
inflationary example of this kind requires the delicate adjustment of potential
parameters (much more than the part-per-mille level), and gives inflation only
at an inflection point of the potential (and so suffers from additional
fine-tuning of initial conditions to avoid an overshoot problem).Comment: 29 pages, 5 figure
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