Counterfactuals Causal inference is easier when the effects are large and sudden. The COVID-19 pandemic and accompanying policy measures caused economic disruption so stark that sophisticated statistical approaches were unnecessary for many questions. For example, unemployment jumped sharply in the early weeks of the pandemic, leaving little room for alternative explanations.
相比那些容易堆砌在发布会 PPT 上的纸面参数，宝马最在意的依然是车辆的动态表现。
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// nothing will ever clean this up。业内人士推荐电影作为进阶阅读
所以去年11月起我们就不接去伊朗的团了，今年1月底，整个中东的新团我们都停接了。当时我只盼能把已经接了的团顺利走完，没想到最后还是遇上了这样的事。