按书上说的，var不应该是减小吗

var值不是置信区间 数值和时间构成吗，为什么可以鉴定出风险因素（我对第四个的理解就是他能分辨出组合的主要风险是什么，如信用风险或操作风险等等）

老师您好，这个式子中Ft是带有%的吗？书上那些公式如何区分Ft是有%的还是没有%的？

6. A portfolio manager is examining data regarding various index futures contracts traded at the CME Group. Which of the following observations would the portfolio manager most likely view as a potential problem? A. The volume in a specific contract is greater than the open interest. B. One specific contract is of a much smaller size than the others. C. The prior settlement price for a specific contract is above the opening price. D. In a specific contract, the last day on which trading can occur is not specified. Correct Answer: D 老师好，这题怎么回事

这题的call的price美式期权不需要折现吧？怎么回事？

An investor has entered into a forward rate agreement where she has contracted to pay a fixed rate of 5 percent on $5,000,000 based on the quarterly rate in three months. If interest rates are compounded quarterly, and the floating rate is 2.5 percent in three months, what is the payoff at the end of the sixth month? 老师，对于FRA，怎么判断其方向（支付还是收到），特别是计算payoff时，讲义里有两个公式，感觉不是很好应用，能否对这块的方向判断做个总结，谢谢。

这个表格里的数据都是指的什么，不太懂上半部分表格的含义

老师这个相关系数r和用协方差标准方差算出来的ρ是一个东西吗

老师您好，对于FRA中的几个时间节点有以下疑惑：1. 合约是在零时刻签订，T1时刻结束，T1是结算日？ 2. 市场利率变化，我的profit或loss为什么是在T2时刻实现的？ 3. T1时刻结算profit或loss，但却没有现金支付？

老师，如果这道题，题目改成null hypothesis that the population mean is larger than or eual to 45. 我仍然是一样计算，但算出来的结论仍然是Z统计量大于关键值，我怎么能得出不能拒绝原假设呢？