问题如下图:
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选项:
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解释:
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tracking error, 在这里为什么不是组合的波动-benchmark的波动?
这里算方差不需要带权重吗?
σp^2+σb^2-2*ρ*σp*σb=(σp-σb)^2=∑(Rp-Rb)^2?
(σp-σb)^2=∑(Rp-Rb)^2?
我在计算tracking error的时候用的是 correlation*benchmark的标准差除以portfolio的标准差。请问是可以接受的通用方法吗?因为计算结果也是