这个题里哪个词看出来是问CPI的“作用”了？characteristic的意思是特点吧

这么长的题 考试会考到吗？这是原题吗？

Fundamental analysts assume that markets are: A Weak-form inefficient. B Semi-strong-form efficient. C Semi-strong-form inefficient. 为什么选C不是A 基本面分析A也可以啊

请问老师，在common share中介绍，shareholders是有voting rights的。preference shares又有common share的特征，为何就没有voting rights呢？

B选项怎么理解？

衰退最底部，应该是劳动生产率最低吧。因为随着衰退的进行，企业渐渐降低了劳动生产率，在底部时劳动生产率最低

A的roll yield是什么意思

A mutual fund manager wants to create a fund based on a high-grade corporate bond index. She first distinguishes between utility bonds and industrial bonds; she then, for each segment, defines maturity intervals of less than 5 years, 5 to 10 years, and greater than 10 years. For each segment and maturity level, she classifies the bonds as callable or noncallable. She then randomly selects bonds from each of the subpopulations she has created. For the manager’s sample, which of the following best describes the sampling approach? A Stratified random. B Simple random. C Systematic. 上一题  正确答案A 您的答案B 本题平均正确率：92% Sampling, time-series and cross-sectional data难度：一般 推荐：      答案解析 In stratified random sampling, one divides the population into subpopulations and randomly samples from within the subpopulations. 请问： 1.分层是一定要求每组中有固定比例吗？ 2.系统抽样是每组中第Kth个的那种吗？

Which of the following characteristics of an investment study most likely indicates time-period bias? A The study is based on a short time-series. B Information not available on the test date is used. C A structural change occurred prior to the start of the study’s time series. 查看解析 上一题 下一题 正确答案A 您的答案A本题平均正确率：65% Biases难度：一般 推荐：      答案解析 A short time series is likely to give period-specific results that may not reflect a longer time period. 请问：C选项的如果不是发生在之前 结构性变化和时间性偏差有和关联，可否举例解释一下，便于理解哈？

The aggregate demand curve是什么？经济学里有这个概念吗？