1,057 research outputs found

    Analysis of some global optimization algorithms for space trajectory design

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    In this paper, we analyze the performance of some global search algorithms on a number of space trajectory design problems. A rigorous testing procedure is introduced to measure the ability of an algorithm to identify the set of ²-optimal solutions. From the analysis of the test results, a novel algorithm is derived. The development of the novel algorithm starts from the redefinition of some evolutionary heuristics in the form of a discrete dynamical system. The convergence properties of this discrete dynamical system are used to derive a hybrid evolutionary algorithm that displays very good performance on the particular class of problems presented in this paper

    Warfare, Fiscal Capacity, and Performance

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    We exploit differences in casualties sustained in pre-modern wars to estimate the impact of fiscal capacity on economic performance. In the past, states fought different amounts of external conflicts, of various lengths and magnitudes. To raise the revenues to wage wars, states made fiscal innovations, which persisted and helped to shape current fiscal institutions. Economic historians claim that greater fiscal capacity was the key long-run institutional change brought about by historical conflicts. Using casualties sustained in pre-modern wars to instrument for current fiscal institutions, we estimate substantial impacts of fiscal capacity on GDP per worker. The results are robust to a broad range of specifications, controls, and sub-samples

    Pollution, Public Health Care, and Life Expectancy When Inequality Matters

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    We analyze the link between economic inequality in terms of wealth, life expectancy, health care and pollution. The distribution of wealth is decisive for the number of households investing in human capital. Moreover, the willingness to invest in human capital depends on agents' life expectancy which determines the length of the amortization period of human capital investments. Life expectancy is positively affected by public health care expenditures but adversely affected by the pollution stock generated by aggregate production. Our model accounts for an endogenous take-off in terms of human capital investments. Higher initial inequality delays the take-off because a given set of policies (abatement measures and public health care) is less effective in improving agents' survival probabilities. We compare a change in taxes to a change in expenditure shares on health hand abatement given different amounts of (initial) inequality. The advantage of the latter as compared to the former is the achieved increase in the tax base which induces more expenditures on health care and abatement measures, such that an even higher economic activity is compatible with a similar level of long-run pollution

    Facts and distortions in an endogenous growth model with physical capital, human capital and varieties

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    This article studies a model with physical and human capital accumulation and varieties. The model includes several distortions: duplication effects, spillovers, creative destruction, surplus appropriability, and an erosion effect. We show that the duplication effect in R&D is essential to make the model replicate several stylized facts linked with R&D. We evaluate the distance to the optimal solution, comparing the strength of each distortion.info:eu-repo/semantics/publishedVersio
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