Yazarlar

  • MakaleAçık Erişim2023Scopus SJRQ1
    Daily precipitation performances of regression-based statistical downscaling models in a basin with mountain and semi-arid climates

    Şan, Murat; Nacar, Sinan; Kankal, Murat; Bayram, Adem

    The impacts of climate change on current and future water resources are important to study local scale. This study aims to investigate the prediction performances of daily precipitation using five regression-based statistical downscaling models (RBSDMs), for the first time, and the ERA-5 reanalysis dataset in the Susurluk Basin with mountain and semi-arid climates for 1979–2018. In addition, comparisons were also performed with an artificial neural network (ANN). Before achieving the aim, the effects of atmospheric variables, grid resolution, and long-distance grid on precipitation prediction were holistically investigated for the first time. Kling-Gupta efficiency was modified and used for holistic evaluation of statistical moments parameters at precipitation prediction comparison. The standard triangular diagram, quite new in the literature, was also modified and used for graphical evaluation. The results of the study revealed that near grids were more effective on precipitation than single or far grids, and 1.50° × 1.50° resolution showed similar performance to 0.25° × 0.25° resolution. When the polynomial multivariate adaptive regression splines model, which performed slightly higher than ANN, tended to capture skewness and standard deviation values of precipitations and to hit wet/dry occurrence than the other models, all models were quite well able to predict the mean value of precipitations. Therefore, RBSDMs can be used in different basins instead of black-box models. RBSDMs can also be established for mean precipitation values without dry/wet classification in the basin. A certain success was observed in the models; however, it was justified that bias correction was required to capture extreme values in the basin.

    AtıfScopus26WoS27
    İncele
  • MakaleYalnız künye2020Scopus SJRQ4
    Betting on the Future: A Comparison Macroeconomic Dynamics of Labour Income Share in The United States: Evidence From MARS

    Çelik, Orkun

    Macroeconomic dynamics of the labour income share (herein: lis) in the United States for the period of 1948Q1-2019Q1 are tried to be determined in this study, where the Multivariate Adaptive Regression Splines (will be referred to herein as MARS) approach is employed. In order to investigate sectorial differences, the business, non-farm, and non-finance sectors are evaluated, respectively. In accordance with the results obtained, it may be observed that the macroeconomic dynamics of lis in the business sector are productivity, export, profit, gross private domestic investment, unemployment rate, current account balance, gross domestic product, and tax revenue, respectively. Related macroeconomic dynamics of lis concerning non-farm sector are productivity, current account balance, gross private domestic investment, export, consumer price index, gross domestic product, profit, unemployment rate, and gross government investment.

  • MakaleYalnız künye2020Scopus SJRQ4
    Macroeconomic Dynamics of Labour Income Share in the United States: Evidence From MARS

    Çelik, Orkun

    Macroeconomic dynamics of labour income share (will be referred to herein as lis) in the United States for the period of 1948Q1-2019Q1 are tried to be determined in this study, where Multivariate Adaptive Regression Splines (will be referred to herein as MARS) approach is employed. In order to investigate sectoral differences, the business, non-farm, and non-finance sectors are evaluated, respectively. In accordance with the obtained results, it may be observed that the macroeconomic dynamics of lis in the business sector are productivity, export, profit, gross private domestic investment, unemployment rate, current account balance, gross domestic product, and tax revenue, respectively. Related macroeconomic dynamics of lis concerning non-farm sector are productivity, current account balance, gross private domestic investment, export, consumer price index, gross domestic product, profit, unemployment rate, and gross government investment. Aforementioned dynamics for non-finance sector are also profit, productivity, import, gross domestic product, tax revenue, gross government investment, consumer price index, and unemployment rate. In accordance with this, the most significant dynamic with respect to lis is profit in the non-finance sector, while it is productivity in the business and non-farm sectors.