The Experts below are selected from a list of 223734 Experts worldwide ranked by ideXlab platform

Ernd Huwe - One of the best experts on this subject based on the ideXlab platform.

  • analysing flow patterns from dye tracer experiments in a forest soil using extreme value statistics
    European Journal of Soil Science, 2007
    Co-Authors: Christina Ogne, Marti Schlathe, Enjami Wolf, Ernd Huwe
    Abstract:

    Preferential flow of water in soil is now recognized as a common phenomenon. It results in complex flow patterns that can be visualized by dye tracers and increases the risk of pollutants reaching greater depths. We analysed the behaviour of a risk index for vertical solute propagation based on extreme value theory. This risk index can be calculated from binary images of dye-stained soil profiles and is defined as the Form Parameter of the generalized Pareto distribution. We did five tracer experiments with Brilliant Blue and iodide under changing initial (variable initial soil moisture) and experimental conditions (different irrigation rates). Our results indicate some persistence of the risk index against small changes of experimental conditions such as the irrigation rate. On the other hand, it seems to be affected by initial soil moisture. Comparisons of Brilliant Blue and iodide patterns show that the Form Parameter alone is not sufficient to estimate the risk of vertical solute propagation. Therefore we propose to combine the risk index with the scale Parameter of the generalized Pareto distribution.

  • a risk index for characterising flow pattern in soils using dye tracer distributions
    Journal of Contaminant Hydrology, 2005
    Co-Authors: Marti Schlathe, Ernd Huwe
    Abstract:

    A novel risk index for the vulnerability of groundwater by pollutants is defined as the Form Parameter of the Pareto distribution and estimated from dye tracer experiments. The Pareto distribution appears as the limit distribution of the extreme value theory, which has been applied to an idealised model of drops that run along a path. The properties of the risk index are investigated by a Monte Carlo study, where the paths are modelled by means of Gaussian random fields. The method is applied to three profiles obtained from Brilliant Blue tracer experiments of the soil physics group at ETH Zurich. It is shown that a single profile can be rather well characterised by the risk index. However, due to the high variability of the dye tracer profiles, an estimated number of at least 15 profile pictures are necessary to characterise a soil.

Enrico Moretti - One of the best experts on this subject based on the ideXlab platform.

  • the political economy of intergenerational income mobility
    Economic Inquiry, 2011
    Co-Authors: Andrea Ichino, Loukas Karabarbounis, Enrico Moretti
    Abstract:

    The intergenerational elasticity of income is considered one of the best measures of the degree to which a society gives equal opportunity to its members. While much research has been devoted to measuring this reduced-Form Parameter, less is known about its underlying structural determinants. Using a model with exogenous talent endowments, endogenous parental investment in children, and endogenous redistributive institutions, we identify the structural Parameters that govern the intergenerational elasticity of income. The model clarifies how the interaction between private and collective decisions determines the equilibrium level of social mobility. Two societies with similar economic and biological fundamentals may have vastly different degrees of intergenerational mobility depending on their political institutions. We offer empirical evidence in line with the predictions of the model. We conclude that international comparisons of intergenerational elasticity of income are not particularly inFormative about fairness without taking into account differences in politico-economic institutions. (JEL E24, J62, J68, P16)

  • the political economy of intergenerational income mobility
    National Bureau of Economic Research, 2010
    Co-Authors: Andrea Ichino, Loukas Karabarbounis, Enrico Moretti
    Abstract:

    The intergenerational elasticity of income is considered one of the best measures of the degree to which a society gives equal opportunity to its members. While much research has been devoted to measuring this reduced-Form Parameter, less is known about its underlying structural determinants. Using a model with exogenous talent endowments, endogenous parental investment in children and endogenous redistributive institutions, we identify the structural Parameters that govern the intergenerational elasticity of income. The model clarifies how the interaction between private and collective decisions determines the equilibrium level of social mobility. Two societies with similar economic and biological fundamentals may have vastly different degrees of intergenerational mobility depending on their political institutions. We offer empirical evidence in line with the predictions of the model. We conclude that international comparisons of intergenerational elasticity of income are not particularly inFormative about fairness without taking into account differences in politico-economic institutions.

Marti Schlathe - One of the best experts on this subject based on the ideXlab platform.

  • analysing flow patterns from dye tracer experiments in a forest soil using extreme value statistics
    European Journal of Soil Science, 2007
    Co-Authors: Christina Ogne, Marti Schlathe, Enjami Wolf, Ernd Huwe
    Abstract:

    Preferential flow of water in soil is now recognized as a common phenomenon. It results in complex flow patterns that can be visualized by dye tracers and increases the risk of pollutants reaching greater depths. We analysed the behaviour of a risk index for vertical solute propagation based on extreme value theory. This risk index can be calculated from binary images of dye-stained soil profiles and is defined as the Form Parameter of the generalized Pareto distribution. We did five tracer experiments with Brilliant Blue and iodide under changing initial (variable initial soil moisture) and experimental conditions (different irrigation rates). Our results indicate some persistence of the risk index against small changes of experimental conditions such as the irrigation rate. On the other hand, it seems to be affected by initial soil moisture. Comparisons of Brilliant Blue and iodide patterns show that the Form Parameter alone is not sufficient to estimate the risk of vertical solute propagation. Therefore we propose to combine the risk index with the scale Parameter of the generalized Pareto distribution.

  • a risk index for characterising flow pattern in soils using dye tracer distributions
    Journal of Contaminant Hydrology, 2005
    Co-Authors: Marti Schlathe, Ernd Huwe
    Abstract:

    A novel risk index for the vulnerability of groundwater by pollutants is defined as the Form Parameter of the Pareto distribution and estimated from dye tracer experiments. The Pareto distribution appears as the limit distribution of the extreme value theory, which has been applied to an idealised model of drops that run along a path. The properties of the risk index are investigated by a Monte Carlo study, where the paths are modelled by means of Gaussian random fields. The method is applied to three profiles obtained from Brilliant Blue tracer experiments of the soil physics group at ETH Zurich. It is shown that a single profile can be rather well characterised by the risk index. However, due to the high variability of the dye tracer profiles, an estimated number of at least 15 profile pictures are necessary to characterise a soil.

Andrea Ichino - One of the best experts on this subject based on the ideXlab platform.

  • the political economy of intergenerational income mobility
    Economic Inquiry, 2011
    Co-Authors: Andrea Ichino, Loukas Karabarbounis, Enrico Moretti
    Abstract:

    The intergenerational elasticity of income is considered one of the best measures of the degree to which a society gives equal opportunity to its members. While much research has been devoted to measuring this reduced-Form Parameter, less is known about its underlying structural determinants. Using a model with exogenous talent endowments, endogenous parental investment in children, and endogenous redistributive institutions, we identify the structural Parameters that govern the intergenerational elasticity of income. The model clarifies how the interaction between private and collective decisions determines the equilibrium level of social mobility. Two societies with similar economic and biological fundamentals may have vastly different degrees of intergenerational mobility depending on their political institutions. We offer empirical evidence in line with the predictions of the model. We conclude that international comparisons of intergenerational elasticity of income are not particularly inFormative about fairness without taking into account differences in politico-economic institutions. (JEL E24, J62, J68, P16)

  • the political economy of intergenerational income mobility
    National Bureau of Economic Research, 2010
    Co-Authors: Andrea Ichino, Loukas Karabarbounis, Enrico Moretti
    Abstract:

    The intergenerational elasticity of income is considered one of the best measures of the degree to which a society gives equal opportunity to its members. While much research has been devoted to measuring this reduced-Form Parameter, less is known about its underlying structural determinants. Using a model with exogenous talent endowments, endogenous parental investment in children and endogenous redistributive institutions, we identify the structural Parameters that govern the intergenerational elasticity of income. The model clarifies how the interaction between private and collective decisions determines the equilibrium level of social mobility. Two societies with similar economic and biological fundamentals may have vastly different degrees of intergenerational mobility depending on their political institutions. We offer empirical evidence in line with the predictions of the model. We conclude that international comparisons of intergenerational elasticity of income are not particularly inFormative about fairness without taking into account differences in politico-economic institutions.

Loukas Karabarbounis - One of the best experts on this subject based on the ideXlab platform.

  • the political economy of intergenerational income mobility
    Economic Inquiry, 2011
    Co-Authors: Andrea Ichino, Loukas Karabarbounis, Enrico Moretti
    Abstract:

    The intergenerational elasticity of income is considered one of the best measures of the degree to which a society gives equal opportunity to its members. While much research has been devoted to measuring this reduced-Form Parameter, less is known about its underlying structural determinants. Using a model with exogenous talent endowments, endogenous parental investment in children, and endogenous redistributive institutions, we identify the structural Parameters that govern the intergenerational elasticity of income. The model clarifies how the interaction between private and collective decisions determines the equilibrium level of social mobility. Two societies with similar economic and biological fundamentals may have vastly different degrees of intergenerational mobility depending on their political institutions. We offer empirical evidence in line with the predictions of the model. We conclude that international comparisons of intergenerational elasticity of income are not particularly inFormative about fairness without taking into account differences in politico-economic institutions. (JEL E24, J62, J68, P16)

  • the political economy of intergenerational income mobility
    National Bureau of Economic Research, 2010
    Co-Authors: Andrea Ichino, Loukas Karabarbounis, Enrico Moretti
    Abstract:

    The intergenerational elasticity of income is considered one of the best measures of the degree to which a society gives equal opportunity to its members. While much research has been devoted to measuring this reduced-Form Parameter, less is known about its underlying structural determinants. Using a model with exogenous talent endowments, endogenous parental investment in children and endogenous redistributive institutions, we identify the structural Parameters that govern the intergenerational elasticity of income. The model clarifies how the interaction between private and collective decisions determines the equilibrium level of social mobility. Two societies with similar economic and biological fundamentals may have vastly different degrees of intergenerational mobility depending on their political institutions. We offer empirical evidence in line with the predictions of the model. We conclude that international comparisons of intergenerational elasticity of income are not particularly inFormative about fairness without taking into account differences in politico-economic institutions.