NO.PZ2022122701000040
问题如下：
Which of the following types of style analysis use(s) a bottom-up approach to estimate the risk exposures in a portfolio?
选项：
A.Returns-based style analysis only
Holdings-based style analysis only
Both return-based and holdings-based style analysis
解释：
Correct Answer: B
Holdings-based style analysis estimates the portfolio’s risk exposures using the securities held in the portfolio (a bottom-up approach), whereas returns-based style analysis uses portfolio returns to estimate a portfolio’s sensitivities to security market indexes (a top-down approach).
为什么return-based 是 top-down？不是很理解，和Equty里讲的有矛盾吗？
