1,503 research outputs found
Predictable Stock Returns in the United States and Japan: A Study of Long-Term Capital Market Integration
This paper studies the predictability of monthly excess returns on equity portfolios over the domestic short-term interest rate in the U.S. and Japan during the period 1971:1-1989:3. The paper finds that similar variables, including the dividend-price ratio and interest rate variables, help to forecast excess returns in each country. In addition, in the 1980's U.S. variables help to forecast excess Japanese stock returns. There is evidence of common movement in expected excess returns across the two countries, which is suggestive of integration of long-term capital markets.
Modeling peculiar velocities of dark matter halos
We present a simple model that accurately describes various statistical
properties of peculiar velocities of dark matter halos. We pay particular
attention to the following two effects; first, the evolution of the halo
peculiar velocity depends on the local matter density, instead of the global
density. Second, dark matter halos are biased tracers of the underlying mass
distribution, thus halos tend to be located preferentially at high density
regions. For the former, we develop an empirical model calibrated with N-body
simulations, while for the latter, we use a conventional halo bias models based
on the extended Press-Schechter model combined with an empirical log-normal
probability distribution function of the mass density distribution. We find
that compared with linear theory, the present model significantly improves the
accuracy of predictions of statistical properties of the halo peculiar velocity
field including the velocity dispersion, the probability distribution function,
and the pairwise velocity dispersion at large separations. Thus our model
predictions may be useful in analyzing future observations of the peculiar
velocities of galaxy clusters.Comment: This paper was published in MNRAS, 343, 1312 (2003). Owing to an
error in numerical computations, some incorrect results were presented there.
Erratum is to be published in MNRAS. Conclusions of the original version are
unaffected by the correction. This version supersedes the original versio
Deciphering cosmological information from redshift surveys of high-z objects - the cosmological light-cone effect and redshift-space distortion -
The three-dimensional distribution of astronomical objects observed in
redshift space significantly differs from the true distribution since the
distance to each object cannot be determined by its redshift only; for the peculiar velocity field contaminates the true recession velocity of
the Hubble flow, while the true distance for objects at sensitively
depends on the (unknown and thus assumed) cosmological parameters. This hampers
the effort to understand the true distribution of large-scale structure of the
universe. In addition, all cosmological observations are carried out on a
light-cone, the null hypersurface of an observer at . This implies that
their intrinsic properties and clustering statistics should change even within
the survey volume. Therefore a proper comparison taking account of the
light-cone effect is important to extract any cosmological information from
redshift catalogues, especially for . We present recent theoretical
development on the two effects -- the cosmological light-cone effect and the
cosmological redshift-space distortion -- which should play key roles in
observational cosmology in the 21st century.Comment: 28pages, 20 figures, minor revision to match the final version to
appear in Progress of Theoretical Physics Supplement, vol. 133 (1999
Modeling Intra-Cluster Gas in Triaxial Dark Halos : An Analytical Approach
We present the first physical model for the non-spherical intra-cluster gas
distribution in hydrostatic equilibrium under the gravity of triaxial dark
matter halos. Adopting the concentric triaxial density profiles of the dark
halos with constant axis ratios proposed by Jing & Suto (2002), we derive an
analytical expression for the triaxial halo potential on the basis of the
perturbation theory, and find the hydrostatic solutions for the gas density and
temperature profiles both in isothermal and polytropic equations of state. The
resulting iso-potential surfaces are well approximated by triaxial ellipsoids
with the eccentricities dependent on the radial distance. We also find a
formula for the eccentricity ratio between the intra-cluster gas and the
underlying dark halo. Our results allow one to determine the shapes of the
underlying dark halos from the observed intra-cluster gas through the X-ray
and/or the Sunyaev-Zel'dovich effects clusters.Comment: accepted by ApJ, LaTex file, 22 pages, 8 postscript figure
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Changing patterns in corporate financing and the main bank system in Japan
For most of the postwar period, the U.S. and Japan have had polar opposite corporate financial structures. The U.S. system has featured low leverage and low monitoring of corporate management by investors, while the Japanese system has featured high leverage and high monitoring. During the last 15 years, however, the two systems have begun to converge. Leverage has increased in the U.S., particularly when measured by interest expense ratios, and the increase has been concentrated in certain firms. In Japan, leverage has decreased across the board. In the U.S., debt-holders' interests may now be represented more effectively; Jensen (1989) argues that LBO partners are a new organizational form which can monitor corporations more effectively. In Japan, while the role of a main bank as a delegated monitor is similar to the LBO partners in the U.S., the growing use of public debt held by outsiders rather than main banks suggests the opposite trend. This paper uses cross-sectional data to reveal more clearly the changing capital structure of Japanese corporations
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