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。
责任是企业的担当,没有责任就没有未来。
The true revolutionary is guided by a great feeling of love. It is impossible to think of a genuine revolutionary lacking this quality.
数学中发现的快乐是无与伦比的。