Rational parameter rays of the Mandelbrot set

We give a new proof that all external rays of the Mandelbrot set at rational angles land, and of the relation between the external angle of such a ray and the dynamics at the landing point. Our proof is different from the original one, given by Douady and Hubbard and refined by Lavaurs, in several ways: it replaces analytic arguments by combinatorial ones; it does not use complex analytic dependence of the polynomials with respect to parameters and can thus be made to apply for non-complex analytic parameter spaces; this proof is also technically simpler. Finally, we derive several corollaries about hyperbolic components of the Mandelbrot set. Along the way, we introduce partitions of dynamical and parameter planes which are of independent interest, and we interpret the Mandelbrot set as a symbolic parameter space of kneading sequences and internal addresses.Comment: 33 pages, 9 figure

Cross-country heterogeneity and the trade-income relationship

This paper makes the following contributions to the literature on the impact of trade on income. First, we use heterogeneous panel cointegration techniques that are robust to omitted variables and endogenous regressors to estimate the effect of trade on income for 75 developed and developing countries, both for the sample, as a whole, and for each individual country. Second, we use a general-to-specific variable-selection approach to identify important determinants of the effect of trade on income. Our main findings are: (i) A one-percent increase in the trade share of GDP results, on average, in a statistically significant increase in income per worker of about 0.18 percent. This result is in contrast to previous studies, which tend to produce either unreasonably large or statistically insignificant estimates of the impact of trade on income. (ii) There are large cross-country differences in the income effect of trade, in particular, between developed and developing countries. For developed countries the income effect of trade is positive, whereas trade has, on average, a negative impact on income in developing countries. (iii) The cross-country heterogeneity in the impact of trade on income can be explained mainly by cross-country differences in primary export dependence, labor market regulation, and property rights protection. The level of property rights protection is positively related, while the levels of primary export dependence and labor market regulation are negatively related to the income effect of trade.Trade; Income; Cross-country heterogeneity; Panel cointegration; General-to-specific approach

The Long-Run Relationship between Outward FDI and Total Factor Productivity: Evidence for Developing Countries

This paper examines the long-run relationship between outward foreign direct investment (FDI) and total factor productivity for a sample of 33 developing countries over the period 1980-2005. Using panel cointegration techniques, we find that: (i) outward FDI has, on average, a positive long-run effect on total factor productivity in developing countries, (ii) increased factor productivity is both consequence and a cause of increased outward FDI, and (iii) there are large differences in the long-run effects of outward FDI on total factor productivity across countries. Cross-sectional regressions indicate that these cross-country differences in the productivity effects of outward FDI are significantly negatively related to cross-country differences in labor market regulation, whereas there is no statistically significant association between the productivity effects of outward FDI and the level of human capital, the level of financial development, or the degree of trade openness in the home country. --outward FDI,total factor productivity,developing countries,panel cointegration

How does foreign direct investment really affect developing countries` growth?

This paper contributes to the literature on foreign direct investment (FDI) and economic growth in two main ways. First, we examine the effect of FDI on economic growth for 44 developing countries over the period 1970 to 2005 using heterogeneous panel cointegration techniques that are robust to omitted variables and endogenous regressors. In contrast to previous studies, we find that FDI has, on average, a negative effect on growth in developing countries, but that there are large cross-country differences in the growth effects of FDI. Second, we use a general-tospecific model selection approach to systematically search for country-specific factors explaining the cross-country differences in the growth effects of FDI. Contrary to previous results, we find that the cross-country differences in per capita income, human capital, openness, and financial market development cannot explain the cross-country differences in the growth effects of FDI. Instead, the growth effects of FDI are positively related to freedom from government intervention and freedom from business regulation, and negatively related to FDI volatility and natural resource dependence.FDI; Growth; Developing countries; Panel cointegration; General-to-specific approach

A further examination of the export-led growth hypothesis

This paper challenges the common view that exports generally contribute more to GDP growth than a mere change in export volume, as the export-led growth hypothesis predicts. Applying heterogeneous panel cointegration techniques to a production function model with non-export GDP as the dependent variable, we find for a sample of 45 developing countries that: (i) exports have a positive short-run effect on non-export GDP in developing countries, (ii) the long-run effect of exports on non-export output, however, is negative on average, and (iii) there are large differences in the long-run effect of exports on non-export GDP across countries. Evidence from a simple regression analysis suggests that these cross-country differences in the long-run effect of exports on non-export GDP are significantly negatively related to cross-country differences in primary export dependence, business regulation, and labour regulation, whereas there is no statistically significant association between the growth effect of exports and the capacity of a country to absorb knowledge.Export-led growth; Developing countries; Panel cointegration