Explaining the Changes of Income Distribution in China

China has experienced one of the most remarkable increase in inequality over the last decade: the Gini coefficient increasing from 25.7 in 1984 to 37.8 in 1992. Using the recent developments in the theory of income distribution (Benerjee and Newman, 1993; Galor and Zeira, 1993) and a new panel data set about Chinese provincial-urban-level income inequality, this paper finds that inequality increased with the reduction of the share of state-owned enterprises in GDP, high inflation, growth, and (less significantly) the increasing exposure to foreign trade. We also find some evidence for the Director¡¯s Law: income redistribution tends to shift resources from the rich and the poor to the middle class. We do not find schooling and urbanization to be a significant explanatory factor.

Finance and income inequality : test of alternative theories

Although theoretical models make distinct predictions about the relationship between financial sector development and income inequality, little empirical research has been conducted to compare their relative explanatory power. The authors examine the relation between financial intermediary development and income inequality in a panel data set of 91 countries for the period 1960-95. Their results provide evidence that inequality decreases as economies develop their financial intermediaries, consistent with the theoretical models in Galor and Zeira (1993) and Banerjee and Newman (1993). Moreover, consistent with the insight of Kuznets, the relation between the Gini coefficient and financial intermediary development appears to depend on the sectoral structure of the economy: a larger modern sector is associated with a smaller drop in the Gini coefficient for the same level of financial intermediary development. But there is no evidence of an inverted-U-shaped relation between financial sector development and income inequality, as suggested by Greenwood and Jovanovic (1990). The results are robust to controlling for biases introduced by simultaneity.Poverty Impact Evaluation,Environmental Economics&Policies,Health Economics&Finance,Economic Theory&Research,Payment Systems&Infrastructure,Inequality,Economic Theory&Research,Poverty Impact Evaluation,Environmental Economics&Policies,Health Economics&Finance

Percolation on interacting networks with feedback-dependency links

When real networks are considered, coupled networks with connectivity and feedback-dependency links are not rare but more general. Here we develop a mathematical framework and study numerically and analytically percolation of interacting networks with feedback-dependency links. We find that when nodes of between networks are lowly connected, the system undergoes from second order transition through hybrid order transition to first order transition as coupling strength increases. And, as average degree of each inter-network increases, first order region becomes smaller and second-order region becomes larger but hybrid order region almost keep constant. Especially, the results implies that average degree \bar{k} between intra-networks has a little influence on robustness of system for weak coupling strength, but for strong coupling strength corresponding to first order transition system become robust as \bar{k} increases. However, when average degree k of inter-network is increased, the system become robust for all coupling strength. Additionally, when nodes of between networks are highly connected, the hybrid order region disappears and the system first order region becomes larger and secondorder region becomes smaller. Moreover, we find that the existence of feedback dependency links between interconnecting networks makes the system extremely vulnerable by comparing non-feedback condition for the same parameters.First author draf

Finance and Income Inequality: What Do the Data Tell Us?

Although there are distinct conjectures about the relationship between finance and income inequality, little empirical research compares their explanatory power. We examine the relationship between finance and income inequality for 83 countries between 1960 and 1995. Because financial development might be endogenous, we use instruments from the literature on law, finance, and growth to control for this. Our results suggest that, in the long run, inequality is less when financial development is greater, consistent with Galor and Zeira (1993) and Banerjee and Newman (1993). Although the results also suggest that inequality might increase as financial sector development increases at very low levels of financial sector development, as suggested by Greenwood and Jovanovic (1990), this result is not robust. We reject the hypothesis that financial development benefits only the rich. Our results thus suggest that in addition to improving growth, financial development also reduces inequality.

Experimental observation of Weyl points

In 1929, Hermann Weyl derived the massless solutions from the Dirac equation - the relativistic wave equation for electrons. Neutrinos were thought, for decades, to be Weyl fermions until the discovery of the neutrino mass. Moreover, it has been suggested that low energy excitations in condensed matter can be the solutions to the Weyl Hamiltonian. Recently, photons have also been proposed to emerge as Weyl particles inside photonic crystals. In all cases, two linear dispersion bands in the three-dimensional (3D) momentum space intersect at a single degenerate point - the Weyl point. Remarkably, these Weyl points are monopoles of Berry flux with topological charges defined by the Chern numbers. These topological invariants enable materials containing Weyl points to exhibit a wide variety of novel phenomena including surface Fermi arcs, chiral anomaly, negative magnetoresistance, nonlocal transport, quantum anomalous Hall effect, unconventional superconductivity[15] and others [16, 17]. Nevertheless, Weyl points are yet to be experimentally observed in nature. In this work, we report on precisely such an observation in an inversion-breaking 3D double-gyroid photonic crystal without breaking time-reversal symmetry.Comment: 4 pages, 3 figure

Finance and Income Inequality: Test of Alternative Theories

Although theoretical models make distinct predictions about the relation between finance and income inequality, little empirical research has been conducted to compare their relative explanatory power. We examine the relation between financial intermediary development and income inequality in a panel data set of 91 countries for the period of 1960-95. Our results provide reasonably strong evidence that inequality decreases as economies develop their financial intermediaries, consistent with Galor and Zeira (1993) and Banerjee and Newman (1993). Moreover, consistent with the insight of Kuznets, the relation between the Gini coefficient and financial intermediary development depends on the sectoral structure of the economy: a larger modern sector is associated with a smaller drop in the Gini coefficient for the same level of financial intermediary development. However, there is no evidence of an inverted-U shaped relation between financial sector development and income inequality, as suggested by Greenwood and Jovanovic (1990). The results are robust to controlling for biases introduced by simultaneity.Income inequality, financial intermediary development, Kuznets curve

Vegetation responses and trade‐offs with soil‐related ecosystem services after shrub removal: A meta‐analysis

Aim To assess the sustainability of different shrub control practices (fire, mechanical, and chemical), based on their efficacy to control shrubs and their effects on multiple ecosystem service provisions, including possible trade‐off and/or synergy. Methods Using a meta‐analysis approach, this study synthesized results from global shrub removal experiments. Log response ratio (lnR) between the outcome of shrub removal and that of the untreated control was used to estimate proportional changes in soil and vegetation properties resulting from each shrub control practice. Results When forage provisioning is the only service considered, shrub removal could achieve this desirable outcome as indicated by increasing herbaceous biomass. However, observable decreases in litter, biological crust cover, and soil nutrients, as well as increases in bare soil indicated long‐term potential trade‐offs with other ecosystem services (e.g., erosion control service, nutrient cycling); the degree may be influenced by different shrub control methods. Synergistic properties were probably limited to a short‐term boost of herb productivity resulting from short‐term increase in herb biomass and diversity as well as nutrient availability. Conclusion Human‐induced drivers manifested in shrub control practices may change vegetation response. However, management also changed non‐targeted processes, generating potential reduction in several regulating ecosystem services. Continuous monitoring to assess landscape conditions should therefore become the key for adaptive management. Sustainable forage production should focus on strategies to maintain multiple ecosystem services because consideration of those services can lead to long‐term protection of the landscape and provide a broader range of environmental benefits

Quantitative synthesis on the ecosystem services of cover crops

The maintenance of soil health in agro-ecosystems is essential for sustaining agricultural productivity. Through its positive impacts on various soil physical and biological processes, cover cropping can be an important component of sustainable agricultural production systems. However, the practice of cover cropping can be complex, and possible trade-offs between the benefits and side effects of cover crops have not been examined. To evaluate these benefits and potential trade-offs, we quantitatively synthesized different ecosystem services provided by cover crops (e.g., erosion control, water quality regulation, soil moisture retention, accumulation of soil organic matter and microbial biomass, greenhouse gas (GHG) emission, weed and pest control, as well as yield of the subsequent cash crop) using data from previous publications. We used a simple indicator (δ), defined as the ratio of an observed variable (i.e., ecosystem service) under cover crop and under fallow condition, to evaluate the impacts of cover crops on a given ecosystem service. Our results showed that cover crops provided beneficial ecosystem services in most cases, except for an increase in GHG emission (δCO2 = 1.46 ± 0.47 and δN2 O = 1.49 ± 1.22;  ± SD) and in pest (nematode) incidence (δnematode abundance = 1.29 ± 1.61). It is also important to highlight that, in some cases, tillage could offset the extent of ecosystem service benefits provided by cover crops. Based on this synthesis, we argue that cover crops should be incorporated into modern agricultural practices because of the many environmental benefits they offer, particularly the maintenance of soil and ecosystem health. More importantly, there was generally an increase in cash crop yield with cover cropping (δyield = 1.15 ± 0.75), likely due to improvement in various soil processes. Despite its benefits, the complexity of cover crop management should not be overlooked, and site-specific factors such as climate, soil type, cover crop species and tillage practices must be considered in order to optimize the benefits of cover cropping. In addition to crop yield, detailed economic analyses are needed to calculate the direct (e.g., reduction in the amount of chemical fertilizer) and indirect monetary benefits (e.g., the improvement of soil quality) of cover crops. Such a comprehensive analysis could serve as incentive for producers to integrate cover crops into their management practices

Evaluating holistic aggregators efficiently for very large datasets

In data warehousing applications, numerous OLAP queries involve the processing of holistic aggregators such as computing the “top n,” median, quantiles, etc. In this paper, we present a novel approach called dynamic bucketing to efficiently evaluate these aggregators. We partition data into equiwidth buckets and further partition dense buckets into sub-buckets as needed by allocating and reclaiming memory space. The bucketing process dynamically adapts to the input order and distribution of input datasets. The histograms of the buckets and subbuckets are stored in our new data structure called structure trees. A recent selection algorithm based on regular sampling is generalized and its analysis extended. We have also compared our new algorithms with this generalized algorithm and several other recent algorithms. Experimental results show that our new algorithms significantly outperform prior ones not only in the runtime but also in accuracy