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The beauty of instrumental variables is that they allow us to see the world in a new light.

Sometimes you may feel like you’re not good enough, but you are.

A quarry manager needs the precision of an engineer and the vision of a poet.

宇宙是一個(gè)全息圖，關(guān)于它內(nèi)部一切的信息都編碼在其邊界上。