And this is ultimately why when a test ban treaty was signed in 1963, it was only a partial ban.
这就是为什么 1963 年签署禁止试验条约时，只是部分禁止。
英语百科
Sign test
The sign test is a statistical method to test for consistent differences between pairs of observations, such as the weight of subjects before and after treatment. Given pairs of observations (such as weight pre- and post-treatment) for each subject, the sign test determines if one member of the pair (such as pre-treatment) tends to be greater than (or less than) the other member of the pair (post-treatment).