NO.PZ2016071602000016
问题如下:
A relative value hedge fund manager holds a long position in asset A and a short position in asset B of roughly equal principal amounts. Asset A currently has a correlation with asset B of 0.97. The risk manager decides to overwrite this correlation assumption in the variance-covariance-based VAR model to a level of 0.30. What effect will this change have on the resulting VAR measure?
选项:
A.
It increases VAR.
B.
It decreases VAR.
C.
It has no effect on VAR, but changes profit or loss of strategy.
D.
There is not enough information to answer.
解释:
A is correct. Because the position is both long and short, high correlation implies low risk. Conversely, lowering correlation increases risk.
但是哈,组合求var的公式最后不是加上correlation* var1*var2吗,correlation上升,从公式看,不是应该 var增大吗