With only one observation per country, it is impossible to control for unobserved heterogeneity across countries.
由于每个国家只有一个观测结果，因此不可能控制各国间未观察到的异质性。
Only the brave sell at auction, for it is impossible to control who buys or what price they will pay.
只有胆大的人才敢在拍卖行交易，因为在交易会上几乎是无法控制谁会去购买，或是他们要付多少钱。
Only the brave sell at auction, for it is impossible to control who buys or what price they will pay.
只有胆大的人才敢在拍卖行交易，因为在交易会上几乎是无法控制谁会去购买，或是他们要付多少钱。
应用推荐