Public expenditure on education: A review of selected issues and evidence.

The role of education in economic development has been recognised for quite some time in mainstream economic literature. Divergence between the private and social rate of return from education is the rationale for intervention by the state in ensuring equity in opportunity across the population. The so-called `New Growth Theories' predict that higher levels of schooling and better quality of workforce will lead to an increase in the rate of growth, further strengthening the case for public expenditure on education. The outcome of these lines of research also has implications for the financing of education. However, the effectiveness and efficiency of resource allocation by the government has generated considerable debate, both from ideological and technical points of view. It is widely acknowledged that there is a large scope for improvement in both the level, and the quality of publicly-funded education. New institutional arrangements are being designed to address the deficiencies in incentives and monitoring, thereby improving quality.Public expenditure ; Education

Do wavelets really detect non-Gaussianity in the 4-year COBE data?

We investigate the detection of non-Gaussianity in the 4-year COBE data reported by Pando, Valls-Gabaud & Fang (1998), using a technique based on the discrete wavelet transform. Their analysis was performed on the two DMR faces centred on the North and South Galactic poles respectively, using the Daubechies 4 wavelet basis. We show that these results depend critically on the orientation of the data, and so should be treated with caution. For two distinct orientations of the data, we calculate unbiased estimates of the skewness, kurtosis and scale-scale correlation of the corresponding wavelet coefficients in all of the available scale domains of the transform. We obtain several detections of non-Gaussianity in the DMR-DSMB map at greater than the 99 per cent confidence level, but most of these occur on pixel-pixel scales and are therefore not cosmological in origin. Indeed, after removing all multipoles beyond $\ell = 40$ from the COBE maps, only one robust detection remains. Moreover, using Monte-Carlo simulations, we find that the probability of obtaining such a detection by chance is 0.59. We repeat the analysis for the 53+90 GHz coadded COBE map. In this case, after removing $\ell > 40$ multipoles, two non-Gaussian detections at the 99 per cent level remain. Nevertheless, again using Monte-Carlo simulations, we find that the probability of obtaining two such detections by chance is 0.28. Thus, we conclude the wavelet technique does {\em not} yield strong evidence for non-Gaussianity of cosmological origin in the 4-year COBE data.Comment: 7 pages, 5 figures. Revised version including discussion of orientation sensitivity of the wavelet decomposition. MNRAS submitte

Impurity-induced sub-gap bound gap states in alkali doped iron chalcogenide superconductors

Measurements of the local density of states near impurities can be useful for identifying the superconducting gap structure in alkali doped iron chalcogenide superconductors K_xFe_{2-y}Se_2. Here, we study the effects of nonmagnetic and magnetic impurities within a nearest neighbor d-wave and next-nearest neighbor s-wave superconducting state. For both repulsive and attractive nonmagnetic impurities, it is shown that sub-gap bound states exist only for d-wave superconductors with the positions of these bound states depending rather sensitively on the electron doping level. Further, for such disorder Coulomb interactions can lead to local impurity-induced magnetism in the case of d-wave superconductivity. For magnetic impurities, both s-wave and d-wave superconducting states support sub-gap bound states. The above results can be explained by a simple analytic model that provides a semi-quantitative understanding of the variation of the impurity bound states energies as a function of impurity potential and chemical doping level.Comment: 8 pages, 7 figure

Analytical approach to the transition to thermal hopping in the thin- and thick-wall approximations

The nature of the transition from the quantum tunneling regime at low temperatures to the thermal hopping regime at high temperatures is investigated analytically in scalar field theory. An analytical bounce solution is presented, which reproduces the action in the thin-wall as well as thick-wall limits. The transition is first order for the case of a thin wall while for the thick wall case it is second order.Comment: Latex file, 22 pages, 4 Postscript figure