March brings St. Patrick’s Day, the true significance of which has been lost in the froth of green beer and blarney. But without Patrick bringing Christianity to Ireland, Ireland could not have returned it through a rich Insular culture—the written word and the book—to Europe. Now, there is another auspicious moment in the history of learning to add to the month’s calendar of anniversaries: March 7, Significance Day, or—if you will—P Day.
The American Statistical Association—a clerisy for our quantified times—has issued a statement clarifying what a P-value means—or rather doesn’t mean. Indeed, it could be said that by adding up all the things a P-value isn’t you end up with an alarming sense of science in thrall to an absence—P-dolatory—the worship of false significance. As long as your study comparing X and Y ends up with P<0.05, it has found something that is unlikely to be unreal. Science could move forward; your career as an experimentalist had measurable success.