Charles Wheelan

And it is not merely a hypothetical case. Evolutionary biologist Stephen Jay Gould was diagnosed with a form of cancer that had a median survival time of eight months; he died of a different and unrelated kind of cancer twenty years later.3 Gould subsequently wrote a famous article called “The Median Isn’t the Message,” in which he argued that his scientific knowledge of statistics saved him from the erroneous conclusion that he would necessarily be dead in eight months. The definition of the median tells us that half the patients will live at least eight months—and possibly much, much longer than that. The mortality distribution is “right-skewed,” which is more than a technicality if you happen to have the disease.4

Accuracy is a measure of whether a figure is broadly consistent with the truth

is that even the most precise measurements or calculations should be checked against common sense.