Statistical Rethinking, 2nd Edition

8    Conditional Manatees

The manatee (Trichechus manatus) is a slow-moving, aquatic mammal that lives in warm, shallow water. Manatees have no natural predators, but they do share their waters with motor boats. And motor boats have propellers. While manatees are related to elephants and have very thick skins, propeller blades can and do kill them. A majority of adult manatees bear some kind of scar earned in a collision with a boat (FIGURE 8.1, top).¹³⁵

The Armstrong Whitworth A.W.38 Whitley was a frontline Royal Air Force bomber. During the second World War, the A.W.38 carried bombs and pamphlets into German territory. Unlike the manatee, the A.W.38 has fierce natural enemies: artillery and interceptor fire. Many planes never returned from ...