"In observational studies, we often have to rely on assumptions that are not directly testable."

我拥抱挑战，因为它们让我更强大。

机器学习的最终目标是让计算机从经验中学习，并随着时间的推移提高其在任务上的表现。

Every tree we plant today is an investment in tomorrow's clean air, stable climate, and thriving ecosystems.

作家是关注世界的人。