Left Skew L Probability Distribution Function (LS-LPDF) and a New Meteorological Drought Index 左偏型L概率分布函数与一种新的气象干旱指数

2019-11-16T04:45:12Z (GMT) by Wang wanli

Unique standard random variable, t=(x- xL )/ x or t=(x- xA )/ x , for left skew L probability distribution function(LS-LPDF), is totally decided by the boundary condition of standard L probability distribution function, f(+1) being equal to zero, or f(+1)=0 ,  on which left skew property of LS-LPDF entirely and completely is dependent, the meticulous and detailed variation and information in “dry area” is as fully and comprehensively delineated as possible using left skew characteristics of LS-LPDF , because x is real variable , xA or  xL is averaged value of real variable in a temporal and spatial context, x is changes to + from 0,(x- xL )/ x or (x- xA )/ x  is equal to-when x is zero, however,  (x- xL )/ x or (x- xA )/ x  is equal to +1  when x is   +∞  .finally, theoretical 12-levels of meteorological drought index is deduced.