历史数据不能用是不是历史不能预测未来这意思？
问题如下图：
选项：
A. 
B. 
C. 
D. 
解释：
availability of tuse of historict little or no relianon covarianmatrices The use of historicta in non-parametric analysis is a saantage, not aantage. If the estimation periowquiet (volatile) then the estimaterisk measures munrstate (overstate) the current risk level. Generally, the largest Vcannot exceethe largest loss in the historicperio On the other han the remaining choices are all consireaantages of non-parametric metho. For instance, the non-parametric nature of the analysis caccommote skewetta points are realy available, anthere is no requirement for estimates or covarianmatrices. a为什么不选?hs难道反映了偏度吗
历史数据是缺陷?应该是算优点啊。。
availability of tuse of historict little or no relianon covarianmatrices The use of historicta in non-parametric analysis is a saantage, not aantage. If the estimation periowquiet (volatile) then the estimaterisk measures munrstate (overstate) the current risk level. Generally, the largest Vcannot exceethe largest loss in the historicperio On the other han the remaining choices are all consireaantages of non-parametric metho. For instance, the non-parametric nature of the analysis caccommote skewetta points are realy available, anthere is no requirement for estimates or covarianmatrices. 请问B如何理解呢？
availability of tuse of historict little or no relianon covarianmatrices The use of historicta in non-parametric analysis is a saantage, not aantage. If the estimation periowquiet (volatile) then the estimaterisk measures munrstate (overstate) the current risk level. Generally, the largest Vcannot exceethe largest loss in the historicperio On the other han the remaining choices are all consireaantages of non-parametric metho. For instance, the non-parametric nature of the analysis caccommote skewetta points are realy available, anthere is no requirement for estimates or covarianmatrices. 该怎么理解啊？
