老师，为什么在计算所有者权益久期时，负债端部分，Liability Duration要乘以（∆i / ∆y）呢？请详细讲解一下，谢谢。

Mattock, head of research dept. of H&V, a brokerage firm, has decided to change recommendation for Timber from buy to sell. In line with H&V’s procedures, she orally advises other executives of recommendation change before publication. After her conversation with Frampton, one of the executives of H&V, Frampton immediately sells (front running) Timber stock from his own account and some discretionary client accounts. Other personnel also inform certain institutional customers of the changed recommendation before publication and dissemination to all H&V customers. Comment: Mattock violated Standard IV (C) by failing to supervise reasonably and adequately the actions of those accountable to her. She also must ensure that her firm has adequate procedures for unethical practice. Meanwhile, violate II(A), VI(B) Priority of Transaction. 请问为什么 违反了II(A) 投资公司的recommendation 难道算是MNI 吗？这里公司将消息提前传达给了一些客户，但为什么又没有违反III(B) ?

单纯对比options，没有特别明白买call相比于卖put的优势在哪里？

A是什么

这里说的是即将进入萧条，但还不是萧条状态，根据讲义上面163页的内容，收益率曲线应该是inverted的啊，这里为什么又是steepen呢？

老师，callable=pure-call option对么。对于买债权的人来说，是只有义务，以X被买回的义务。当波动率升高，call贵，卖出call可以收更多期权费。对吗

波动率下降，一是依然通过卖call赚期权费，二是callable更便宜，因为value上来看是pure-call，对么

老师，C选项的earnings surprises要怎么理解？

Q8 为什么相同债券OAS越高，折现率越高呢？视频课不是讲Vcall=Z spread- OAS，那这样5债券的OAS最低，Vcall最大，Vcallable5应该最便宜？

老师，能解释一下B选项的limit $50 sell order是什么意思吗？视频解析我没听明白，谢谢。