Determinants of Japanese aid allocation: an econometric analysis

Economic self-interest and politico-strategic and humanitarian concerns motivate donor countries in their development assistance policies. A large amount of literature has pointed out that either economic self-interest or political self-interest played a pivotal role in the early phases of foreign aid programmes of many donors. Currently, almost all donors include humanitarian assistance in explaining their aid motives. We investigate how Japanese aid allocation policies have changed over the time and also identify empirically the major determinants of aid allocation. It is found from the empirical evidence that Japan takes national interest as well as recipient country needs into account in allocating their aid. The nature of Asian biasness in Japanese aid may continue given the high emphasis on national economic and security interests. Given the historical trend one can conclude that the same determinant factors may keep on playing vital roles in aid allocation decision-making at least for some years to come even though there has been an increased call for more assistance to poor region

Gravitational Lensing as a Probe of Quintessence

A large number of cosmological studies now suggest that roughly two-thirds of the critical energy density of the Universe exists in a component with negative pressure. If the equation of state of such an energy component varies with time, it should in principle be possible to identify such a variation using cosmological probes over a wide range in redshift. Proper detection of any time variation, however, requires cosmological probes beyond the currently studied range in redshift of $\sim$ 0.1 to 1. We extend our analysis to gravitational lensing statistics at high redshift and suggest that a reliable sample of lensed sources, out to a redshift of $\sim$ 5, can be used to constrain the variation of the equation of state, provided that both the redshift distribution of lensed sources and the selection function involved with the lensed source discovery process are known. An exciting opportunity to catalog an adequate sample of lensed sources (quasars) to probe quintessence is now available with the ongoing Sloan Digital Sky Survey. Writing $w(z)\approx w_0 + z (dw/dz)_0$, we study the expected accuracy to which the equation of state today $w_0$ and its rate of change $(dw/dz)_0$ can simultaneously be constrained. Such a determination can rule out some missing-energy candidates, such as classes of quintessence models or a cosmological constant.Comment: Accepted for publication in ApJ Letters (4 pages, including 4 figures

Sunyaev-Zeldovich Fluctuations from the First Stars?

WMAP's detection of high electron-scattering optical depth suggests substantial star formation at high redshift z~17 +/- 5. On the other hand, the recovered sigma_8 ~ 0.84 +/-0.04 disfavors a cluster Sunyaev-Zeldovich (SZ) origin for the observed small-scale-CMB fluctuation excess, which generally requires sigma_8 ~ 1.1. Here we consider the effects of high-redshift star formation on the CMB. We derive a fairly model-independent relation between the electron scattering optical depth and the number of ionizing photons emitted per baryon, and use this to calibrate the amount of high-redshift supernova activity. The resulting supernova remnants Compton cool against the CMB creating a Compton-y distortion y ~ few x 10^-6, within observational bounds. However they also create small-scale SZ fluctuations, which could be comparable with SZ fluctuations from unresolved galaxy clusters. This raises the exciting possibility that we have already detected signatures of the first stars not just once, but twice, in the CMB.Comment: Fixed typo in Fig. 1 caption; few other minor change

Distances and Cosmology From Galaxy Cluster CMB Data

The measurement of angular diameter distance to galaxy clusters, through combined Sunyaev-Zel'dovich (SZ) effect data with X-ray emission observations, is now a well-known probe of cosmology. Using a combination of SZ data and a map of the lensed CMB anisotropies by the galaxy cluster potential, we propose an alternative geometric technique to measure distance information primarily through cluster related multi-frequency CMB measurements. We discuss necessary requirements to implement this measurement, potential errors including systematic biases, and the extent to which cosmological parameters can be extracted. While individual cluster distances are not likely to be precise, with upcoming subarcminute resolution wide-area CMB observations, useful information on certain cosmological parameters, such as the equation of state of dark energy, can be obtained from a large sample of galaxy clusters.Comment: 4 pages, 2 figure

An indirect limit on the amplitude of primordial Gravitational Wave Background from CMB-Galaxy Cross Correlation

While large scale cosmic microwave background (CMB) anisotropies involve a combination of the scalar and tensor fluctuations, the scalar amplitude can be independently determined through the CMB-galaxy cross-correlation. Using recently measured cross-correlation amplitudes, arising from the cross-correlation between galaxies and the Integrated Sachs Wolfe effect in CMB anisotropies, we obtain a constraint r < 0.5 at 68% confidence level on the tensor-to-scalar fluctuation amplitude ratio. The data also allow us to exclude gravity waves at a level of a few percent, relative to the density field, in a low - Lambda dominated universe(Omega_Lambda~0.5). In future, joining cross-correlation ISW measurements, which captures cosmological parameter information, with independent determinations of the matter density and CMB anisotropy power spectrum, may constrain the tensor-to-scalar ratio to a level above 0.05. This value is the ultimate limit on tensor-to-scalar ratio from temperature anisotropy maps when all other cosmological parameters except for the tensor amplitude are known and the combination with CMB-galaxy correlation allows this limit to be reached easily by accounting for degeneracies in certain cosmological parameters.Comment: 5 Pages, 1 Figure, revised discussion on cosmic variance limits on the tensor-to-scalar ratio from CMB, matches PRD accepted versio

Parameterization of Dark-Energy Properties: a Principal-Component Approach

Considerable work has been devoted to the question of how to best parameterize the properties of dark energy, in particular its equation of state w. We argue that, in the absence of a compelling model for dark energy, the parameterizations of functions about which we have no prior knowledge, such as w(z), should be determined by the data rather than by our ingrained beliefs or familiar series expansions. We find the complete basis of orthonormal eigenfunctions in which the principal components (weights of w(z)) that are determined most accurately are separated from those determined most poorly. Furthermore, we show that keeping a few of the best-measured modes can be an effective way of obtaining information about w(z).Comment: Unfeasibility of a truly model-independent reconstruction of w at z>1 illustrated. f(z) left out, and w(z) discussed in more detail. Matches the PRL versio

Accounting Education in Australia and Japan: A Comparative Examination

In recent years there has been a great concern among governments, professional bodies and educators for changes in accounting education. It seems useful for planners of such changes to consider the methods of training accountants in different countries as one country can learn from the experiences of another. In the existing literature, however, there is a dearth of comparative studies on this area of education in different countries. This paper presents an analysis of accounting education in Australia and Japan highlighting the major differences in the two countries. The analysis reveals that accounting education in Australia places emphasis on financial accounting while the emphasis is on cost and management accounting in Japan. It also shows that being firm-specific through comprehensive in-house training the Japanese system is in a better position to produce accountants capable of adapting accounting systems to the different work situations which result from technological changes and automation

The Born and Lens-Lens Corrections to Weak Gravitational Lensing Angular Power Spectra

We revisit the estimation of higher order corrections to the angular power spectra of weak gravitational lensing. Extending a previous calculation of Cooray and Hu, we find two additional terms to the fourth order in potential perturbations of large-scale structure corresponding to corrections associated with the Born approximation and the neglect of line-of-sight coupling of two foreground lenses in the standard first order result. These terms alter the convergence ($\kappa\kappa$), the lensing shear E-mode ($\epsilon\epsilon$), and their cross-correlation ($\kappa\epsilon$) power spectra on large angular scales, but leave the power spectra of the lensing shear B-mode ($\beta\beta$) and rotational ($\omega\omega$) component unchanged as compared to previous estimates. The new terms complete the calculation of corrections to weak lensing angular power spectra associated with both the Born approximation and the lens-lens coupling to an order in which the contributions are most significant. Taking these features together, we find that these corrections are unimportant for any weak lensing survey, including for a full sky survey limited by cosmic variance.Comment: Added references, minor changes to text. 9 pages, 2 figure

Modifications to the Cosmic 21-cm Background Frequency Spectrum by Scattering via electrons in Galaxy Clusters

The cosmic 21-cm background frequency spectrum related to the spin-flip transition of neutral Hydrogen present during and before the era of reionization is rich in features associated with physical processes that govern transitions between the two spin states. The intervening electrons in foreground galaxy clusters inversely Compton scatter the 21-cm background spectrum and modify it just as the cosmic microwave background (CMB) spectrum is modified by inverse-Compton scattering. Towards typical galaxy clusters at low redshifts, the resulting modification is a few tenths milli-Kelvin correction to the few tens milli-Kelvin temperature of 21-cm signal relative to that of the cosmic microwave background black body spectrum. The modifications are mostly associated with sharp changes in the cosmic 21-cm background spectrum such as due to the onset of a Lyman-$\alpha$ radiation field or heating of neutral gas. Though low frequency radio interferometers that are now planned for 21-cm anisotropy measurements are insensitive to the mean 21-cm spectrum, differential observations of galaxy clusters with these interferometers can be utilized to indirectly establish global features in the 21-cm frequency spectrum. We discuss the feasibility to detect the spectrum modified by clusters and find that for upcoming interferometers, while a detection towards an individual cluster is challenging, one can average signals over a number of clusters, selected based on the strength of the Sunyave-Zel'dovich effect at high radio frequencies involving CMB scattering alone, to establish the mean 21-cm spectrum.Comment: 6 pages, 3 figures, PRD in press; expanded and title changed from v1. Final version in pres