请问老师，样本误差和标准误有什么潜在联系么？

22 什么叫0 经济利润

为什么股票通常情况下是高峰肥尾巴？

这题B选项不对是因为不能反推，穷举事件可能还有E3，E4...这个意思吗？

老师，为什么前面说中心极限定理的条件之一是：总体的均值和方差已知，后面又说当总体方差未知的时候，用样本方差代替？ 前后矛盾，非常困惑。

infer替代正 收入负 总体正 是啥意思

t the beginning of the year, Company P purchased 1,000 shares of Company S for $80 per share. During the year, Company S paid a dividend of $4 per share. At the end of the year, Company S's share price was $75.What amount should Company P report on its balance sheet at year-end if the investment in Company S is considered a trading security, and what amount should be reported if the investment is considered an available-for-sale security? A $75,000 for trading; $75,000 for available-for-sale B $75,000 for trading; $80,000 for available-for-sale C $80,000 for trading; $80,000 for available-for-sale

12 为什么不是py与px比

***经济学讲义 169页中的前两个，都是工资，171页的第一个也是工资，前者是同期指标，后者是滞后指标。 令人十分费解

2020***经济学讲义171页，prime lending rate为什么是滞后指标，具体什么逻辑？？？请细讲