估计问题的性质不同。在这里，我们不关心检验特定的假设，而是关心估计参数的值。

You can have a lifetime of trying to get away from where you started out, and it’s only when you get there you realize you’ve brought it with you.

"To write is to explore the uncharted territories of the human mind and to bring back treasures of insight."

有时候，帮助某人的最好方式就是陪伴在他们身边。

There is no lasting hope in violence，only temporary relief from hopelessness.

贪婪读书，终生学习，保持好奇，日日增慧。