Through the long-term plot study on the litter and its decomposition in the evergreen broad-leaved forest ecosystem in Hangzhou for more than two years,it was resulted that the annual litter production was 5.85 t ha^-...Through the long-term plot study on the litter and its decomposition in the evergreen broad-leaved forest ecosystem in Hangzhou for more than two years,it was resulted that the annual litter production was 5.85 t ha^-1,most of which was the fallen leave (79.5 percent) and the withered branches and fruits were far less (7.1 and 13.4 percents respectively).The dynamics of the fallen litter was shown as a curve of two-peak pattern which appeared in April and September each year.The half-life of the litter was 1.59 years.The decay rate of the litter attenuted as an exponential function.The annual amount of the nutrient returned to the ground through the litter was as large as 223.69kg ha^-1.The total current amount of the litter on the ground was 7.47t ha^-1.The decay rate in the first half of a year was 45.18 percent.This ecosystem remained in the stage of litter increasing with time.展开更多
By decomposing asset returns into potential maximum gain(PMG)and potential maximum loss(PML)with price extremes,this study empirically investigated the relationships between PMG and PML.We found significant asymmetry ...By decomposing asset returns into potential maximum gain(PMG)and potential maximum loss(PML)with price extremes,this study empirically investigated the relationships between PMG and PML.We found significant asymmetry between PMG and PML.PML significantly contributed to forecasting PMG but not vice versa.We further explored the power of this asymmetry for predicting asset returns and found it could significantly improve asset return predictability in both in-sample and out-of-sample forecasting.Investors who incorporate this asymmetry into their investment decisions can get substantial utility gains.This asymmetry remains significant even when controlling for macroeconomic variables,technical indicators,market sentiment,and skewness.Moreover,this asymmetry was found to be quite general across different countries.展开更多
Under the assumption that asset prices follow a mixed gamma process,this paper first shows that return series can be presented as a difference of two gamma processes and then proposes a realized probability index for ...Under the assumption that asset prices follow a mixed gamma process,this paper first shows that return series can be presented as a difference of two gamma processes and then proposes a realized probability index for return direction forecasting.The underlying distribution of this new index is analyzed and found to be beta-distributed.Both theoretical and empirical results show that this new index is more efficient than the traditional binary index.展开更多
基金Project supported by the Laboratory of Material Cycling in Pedosphere, Insitute of Soil Science, Chinese Academy of Sciences.
文摘Through the long-term plot study on the litter and its decomposition in the evergreen broad-leaved forest ecosystem in Hangzhou for more than two years,it was resulted that the annual litter production was 5.85 t ha^-1,most of which was the fallen leave (79.5 percent) and the withered branches and fruits were far less (7.1 and 13.4 percents respectively).The dynamics of the fallen litter was shown as a curve of two-peak pattern which appeared in April and September each year.The half-life of the litter was 1.59 years.The decay rate of the litter attenuted as an exponential function.The annual amount of the nutrient returned to the ground through the litter was as large as 223.69kg ha^-1.The total current amount of the litter on the ground was 7.47t ha^-1.The decay rate in the first half of a year was 45.18 percent.This ecosystem remained in the stage of litter increasing with time.
基金This research is supported by National Natural Science Foundation of China under Grant No.71401033Program for Young Excellent Talents,UIBE under Grant No.15YQ08.
文摘By decomposing asset returns into potential maximum gain(PMG)and potential maximum loss(PML)with price extremes,this study empirically investigated the relationships between PMG and PML.We found significant asymmetry between PMG and PML.PML significantly contributed to forecasting PMG but not vice versa.We further explored the power of this asymmetry for predicting asset returns and found it could significantly improve asset return predictability in both in-sample and out-of-sample forecasting.Investors who incorporate this asymmetry into their investment decisions can get substantial utility gains.This asymmetry remains significant even when controlling for macroeconomic variables,technical indicators,market sentiment,and skewness.Moreover,this asymmetry was found to be quite general across different countries.
基金supported by the National Natural Science Foundation of China under Grant Nos.72271055 and 12201113。
文摘Under the assumption that asset prices follow a mixed gamma process,this paper first shows that return series can be presented as a difference of two gamma processes and then proposes a realized probability index for return direction forecasting.The underlying distribution of this new index is analyzed and found to be beta-distributed.Both theoretical and empirical results show that this new index is more efficient than the traditional binary index.
