问题如下图：
选项：
A. 
B. 
C. 
解释：
你好 请问r是什么利率，为什么不可以是负数呢？
NO.PZ2018062010000008问题如下The followings are some scriptions of fferent kin of ration. Whiis most accurate?A.Macaulration is usefor measuring the curve ration.B.Effective ration measures interest rate risk in terms of a nonparallel shift in the benchmark yielcurve.C.A bons Macaulration always larger thits mofieration. C is correct.A bons Macaulration always larger thits mofieration. The relationship between Macaulration anmofieration is presentefollowing:Mofie ration=Macaulay ration1+rMofie;ration=\frac{Macaulay\;ration}{1+r}Mofieuration=1+rMacaulayrationWhere r is yielper periowhiis always larger thzero. penng on this, the nominator ( 1 + r ) is always larger th1. So a bons Macaulration always larger thits mofieration.A is incorrebecause Macaulration is usefor measuring the yielration, not the curve ration.B is incorrebecause effective ration measures interest rate risk in terms of a parallel shift in the benchmark yielcurve.考点ration解析effective ration而非Macaulration衡量的是curve ration，A说法不正确。有效久期衡量利率风险的时候，假设的是benchmark利率曲线发生一个平行移动，而不是nonparallel shift。parallel shift是指收益率曲线发生平行移动，也就是曲线上的每一个点都变动相同的幅度。B说法不正确。修正久期等于麦考利久期/(1+一期的市场利率)，市场利率通常情况下＞0,因此（1+市场利率）通常情况下大于1。所以，C说法正确，当选。 衡量nonparallel的是哪一种久期
那什么测量 curve ration？
请问B 讲的是什么？
