Just for people who might come along later: It looks like the author is talking about setting a threshold, as in the context of creating a test. Please have a

Just for people who might come along later: It looks like the author is talking about setting a threshold, as in the context of creating a test. Please have a look at [1]. In this setting, it is not possible to decrease the false-negative rate without increasing the false-positive rate. I think the author is phrasing things this way simply as a matter of rhetoric, not to express the point you are suggesting. 1. http://www.prolekare.cz/dbpic/jp_5403_f_21-x1000_1600 http://www.prolekare.cz/dbpic/jp_5403_f_21-x1000_1600