Claude is looking for a link between time spent eating and hunger. He thinks that students who eat faster will be more hungry two hours later. He observes how much time some students spend eating their lunch. They are unaware that they are being observed. Two hours later, he asks them to rate their hunger on a scale of 1 to 10 (1 = not hungry, 10 = very hungry). He correlates how hungry they are with how much time they spent eating lunch. He finds there is a strong negative correlation between time spent eating and hunger.