,没有高手理我

these are the factors that are hard to decide and that's where subjective decisions need to be made in the modeling process. usually these ratios are either determined by regression models or from empirical experiences. You can also get these ratios through industry surveys and interviews, at least that was how I got them when I was working with a consulting company. (sorry I am using a computer that has no Chinese, I will re-edit it in Chinese when I come around)

谢谢，我看懂了

我也有同样的疑问。。。
我看过一些文献，好像是用表函数
或者一些是用一些相关因子的乘积。。。
不懂楼主现在有何进展了？

我也同意，好像应该用LOOK UP函数来表示