请问图片中的3/4是怎么来的？

为什么算出协方差就是两者都违约的概率呢

为什么五年违约的概率要用1-0.99^5算呢 不能直接用（1%)^5吗

那些公式简写是在哪一章？ESS，RSS，R平方

Ess是什么意思

这里的F-test与t-test在哪节课啊，之前的视频都没看到

老师这个推导能详细分析一下吗

请问1980年储蓄危机和雷曼兄弟倒闭有什么相同和区别,这个是这几天考试原题

老师 LN(117.94/100) =0.165, 这里为啥要除100

老师这道题为什么和官网不一样，官网是：A quantitative analyst at a proprietary trading firm is incorporating unsupervised machine learning (ML) algorithms into the firm’s technical analysis of equities by using K-means clustering. The clustering algorithm will be applied to continuous volatility data in order to group observations into clusters that can be used to identify the current market regime. Since clusters close to each other are likely to exhibit similar characteristics, the analyst measures the distances between the observations within each cluster and the centroid of that cluster. If the analyst wants to ensure that the minimum distance is obtained for the continuous data clusters when applying the K-means algorithm, which measure should be used to achieve the desired outcome? A.Euclidean distance B.Manhattan distance C.Cook’s distance D.Gini measure麻烦解答一下