On US politics and IMF Lending

The political factors, which shape IMF lending to LDCs, have attracted much attention. The same goes for the role and influence of the US. However, formal modelling is scant. In this paper, we assume that the US is principal within the IMF and seeks to maximize its impact on the policy stance of debtor countries. We derive the optimal loan allocation mechanism, and test the hypothesis that the probability of an IMF loan is increasing in the amount of political concessions countries make. A political concession is defined as the distance between a country’s bliss point and its actual policy stance measured relative to the US. We propose a bliss-point proxy and test our hypothesis in a sample of 68 countries during the period 1986-94. There is support for our hypothesis in the data. Finally, we show that omitting bliss points may lead to endogeneity bias in empirical work.IMF lending; political factors

Mice Do Not Take Bribes

This paper explores the empirical association between internet use, e-government and corruption in a large panel of countries covering the 1998-2003 period. We show that higher numbers of internet users and higher levels of e-government are associated with significantly lower levels of corruption. Controlling for most variables used in previous work on corruption and addressing the endogeneity issue, results are shown to be robust and to carry economic significance. This leads us to conclude that well-designed ICT policies are likely to bring substantial benefits in the fight against corruption.corruption; ICT; internet; e-government

Physical approach to quantum networks with massive particles

This paper treats a quantum network from a physical approach, explicitly finds the physical eigenstates and compares them to the quantum-graph description. The basic building block of a quantum network is an X-shaped potential well made by crossing two quantum wires, and we consider a massive particle in such an X well. The system is analyzed using a variational method based on an expansion into modes with fast convergence and it provides a very clear intuition for the physics of the problem. The particle is found to have a ground state that is exponentially localized to the center of the X well, and the other symmetric solutions are formed so to be orthogonal to the ground state. This is in contrast to the predictions of the conventionally used so-called Kirchoff boundary conditions in quantum graph theory that predict a different sequence of symmetric solutions that cannot be physically realized. Numerical methods have previously been the only source of information on the ground-state wave function and our results provide a different perspective with strong analytical insights. The ground-state wave function has the shape of a solitonic solution to the non-linear Schr{\"o}dinger equation, enabling an analytical prediction of the wave number. When combining multiple X wells into a network or grid, each site supports a solitonic localized state. The solitons only couple to each other and are able to jump from one site to another as if they were trapped in a discrete lattice.Comment: 22 pages, 21 figures, technical appendices included. Webpage abstract slightly abridged. Comments are most welcom

Internal computational fluid mechanics on supercomputers for aerospace propulsion systems

The accurate calculation of three-dimensional internal flowfields for application towards aerospace propulsion systems requires computational resources available only on supercomputers. A survey is presented of three-dimensional calculations of hypersonic, transonic, and subsonic internal flowfields conducted at the Lewis Research Center. A steady state Parabolized Navier-Stokes (PNS) solution of flow in a Mach 5.0, mixed compression inlet, a Navier-Stokes solution of flow in the vicinity of a terminal shock, and a PNS solution of flow in a diffusing S-bend with vortex generators are presented and discussed. All of these calculations were performed on either the NAS Cray-2 or the Lewis Research Center Cray XMP

Power outages and economic growth in Africa

This paper estimates the total effect of power outages on economic growth in Sub-Saharan Africa over the period 1995-2007. Outages are instrumented using a satellite-based measure of lightning density. As suggested by Henderson et al. (2011), we also combine Penn World Tables GDP data with satellite-based data on nightlights to arrive at a more accurate measure of economic growth. Our results suggest that the annual economic growth drag of a weak power infrastructure is about 2 percentage points.Economic growth; public utilities; electricity; earthlights; Africa

Cross-Border Flows of People, Technology Diffusion and Aggregate Productivity

A number of empirical studies have investigated the hypothesis that cross-border flows of goods (international trade) and capital (FDI) lead to international technology diffusion. The contribution of the present paper consists in examining an as yet neglected vehicle for technology diffusion: cross-border flows of people. We find that increasing the intensity of international travel, for the purpose of business and otherwise, by 1% increases the level of aggregate total factor productivity and GDP per worker by roughly 0.2%.technology diffusion; productivity; IV estimation

Digging deeper: How do different types of organic consumers influence the increasing organic market share?

The purpose of this paper is to investigate how sub markets with different degrees of maturity develop during a period of general organic growth, and how different consumer segments behave on these sub markets. The paper uses actual purchasing behaviour of six consumer segments with different attitudes towards food in general and organic production and products in particular. The data is from the Danish market for organic foods, which is one of the most mature markets in the world. The segmentation splits consumers into a positive and a non-positive half, each half consisting of three different segments. The estimations show that the development in general organic consumption varies between segments, and that their behaviour varies between sub markets. The positive half of the population has driven the overall growth in organic budget share at the Danish market over the period 2005 to 2007, while the other half have not changed their consumption significantly. The results indicate that for the most dedicated organic consumers, the organic budget share may be approaching a saturation point for some types of food, but also identifies other types of food which still have a growing organic budget share, even among the most dedicated consumers. The combination of attitudes and actual behaviour for a large number of consumers is new, and the results provide a valuable contribution to the ongoing investigation of organic consumers, and provide new nuances to the understanding of the latest organic growth.organic budget shares, organic consumers, consumer segments, latent class analysis, demand

Congruence of chloroplast- and nuclear-encoded DNA sequence variations used to assess species boundaries in the soil microalga Heterococcus (Stramenopiles, Xanthophyceae).

BackgroundHeterococcus is a microalgal genus of Xanthophyceae (Stramenopiles) that is common and widespread in soils, especially from cold regions. Species are characterized by extensively branched filaments produced when grown on agarized culture medium. Despite the large number of species described exclusively using light microscopic morphology, the assessment of species diversity is hampered by extensive morphological plasticity.ResultsTwo independent types of molecular data, the chloroplast-encoded psbA/rbcL spacer complemented by rbcL gene and the internal transcribed spacer 2 of the nuclear rDNA cistron (ITS2), congruently recovered a robust phylogenetic structure. With ITS2 considerable sequence and secondary structure divergence existed among the eight species, but a combined sequence and secondary structure phylogenetic analysis confined to helix II of ITS2 corroborated relationships as inferred from the rbcL gene phylogeny. Intra-genomic divergence of ITS2 sequences was revealed in many strains. The 'monophyletic species concept', appropriate for microalgae without known sexual reproduction, revealed eight different species. Species boundaries established using the molecular-based monophyletic species concept were more conservative than the traditional morphological species concept. Within a species, almost identical chloroplast marker sequences (genotypes) were repeatedly recovered from strains of different origins. At least two species had widespread geographical distributions; however, within a given species, genotypes recovered from Antarctic strains were distinct from those in temperate habitats. Furthermore, the sequence diversity may correspond to adaptation to different types of habitats or climates.ConclusionsWe established a method and a reference data base for the unambiguous identification of species of the common soil microalgal genus Heterococcus which uses DNA sequence variation in markers from plastid and nuclear genomes. The molecular data were more reliable and more conservative than morphological data

Eye Disease and Development

This research advances the hypothesis that cross-country variation in the historical incidence of eye disease has influenced the current global distribution of per capita income. The theory is that pervasive eye disease diminished the incentive to accumulate skills, thereby delaying the fertility transition and the take-off to sustained economic growth. In order to estimate the influence from eye disease incidence empirically, we draw on an important fact from the field of epidemiology: Exposure to solar ultraviolet B radiation (UVB-R) is an underlying determinant of several forms of eye disease; the most important being cataract, which is currently the leading cause of blindness worldwide. Using a satellite-based measure of UVB-R, we document that societies more exposed to UVB-R are poorer and underwent the fertility transition with a significant delay compared to the forerunners. These findings are robust to the inclusion of an extensive set of climate and geography controls. Moreover, using a global data set on economic activity for all terrestrial grid cells we show that the link between UVB-R and economic development survives the inclusion of country fixed effect.Comparative development, eye disease, climate