没看懂这道题考点 问题如下图：
选项：
A. 
B. 
C. 
D. 
解释：
品职答疑小助手雍 · 2019年04月13日
同学你好，这题考察的就是KMVmodel，问的是关于KMV模型算的违约概率的结果，哪个是对的。
A：公司杠杆降低时（Asset里debt的比例变低），公司越不容易违约（正确），因为asset离debt距离远了。A对
B：股价上升（Asset中debt的比例变低），和A同理，违约率会变小而不是变大，B错。
C：EDF和risk-neuutral PD不完全一样（还有波动率等其他参数，不只有Rf），C错。
D：EDF不能延伸到correlation，KMV模型的套用可以。D错。
朵朵0927 · 2020年03月07日
老师，您说的d没看懂是什么意思，请帮忙解释下，谢谢
品职答疑小助手雍 · 2020年03月07日
Kmv模型本身是通过把equity price与公司资产建立联系来算PD的模型，别的一些方法套用KMV的原理情况是可以用于测算correlation的，不过KMV模型本身是不能计算几个债券之间的correlation的，所以D不对
The KMV mol proces a measure calleexpectefault frequency. Whiof the following statements about this variable is correct? It creases when the leverage of the firm falls. It increases when the stopriof the firm hbeen rising. It is the risk-neutrprobability of fault from Merton’s mol. It tells investors how the fault risk of a bonis correlatewith the fault risk of other bon in the portfolio ANSWER: A The E, similarly to the risk-neutrP creases when the stoprigoes up, when the leverage goes wn, or when the volatility goes wn. It is a transformation of the Pfrom a Merton-type mol. The KMV framework cextento finng correlations, but the E is not sufficient. 为什么当stoprigoes up，or leverage goes wn时，会下降？
It increases when the stopriof the firm hbeen rising. It is the risk-neutrprobability of fault from Merton’s mol. It tells investors how the fault risk of a bonis correlatewith the fault risk of other bon in the portfolio ANSWER: A The E, similarly to the risk-neutrP creases when the stoprigoes up, when the leverage goes wn, or when the volatility goes wn. It is a transformation of the Pfrom a Merton-type mol. The KMV framework cextento finng correlations, but the E is not sufficient. 请问一下C和应讲义的哪里？
It increases when the stopriof the firm hbeen rising. It is the risk-neutrprobability of fault from Merton’s mol. It tells investors how the fault risk of a bonis correlatewith the fault risk of other bon in the portfolio ANSWER: A The E, similarly to the risk-neutrP creases when the stoprigoes up, when the leverage goes wn, or when the volatility goes wn. It is a transformation of the Pfrom a Merton-type mol. The KMV framework cextento finng correlations, but the E is not sufficient. E在讲义的哪一部分？
能具体一下C、？1.C中E与Merton mol的risk neutrP底有什么区别？前者时由历史数据获得，后者是由二叉树获得？2.课时候KMV好像没有讲到ρ的关系把？