Idea: We cannot measure the closeness of the estimates with the population parameter directly, but it is possible to use data from a random sample to construct a set of values that contains the true value with a certain specified probability.

• 我们无法直接衡量估计值和总体参数之间的距离，但是利用来自随机样本的数据构造一个取值的集合，使得真值在给定概率下属于这个集合是可能的。