Judy is considering the purchase of a new Kitchen Maid dishwasher. Judy's friend Jasper bought a new Kitchen Maid six months ago, and he finds that the dishwasher gets his dishes, cups, glasses, and eating utensils sparkling clean. Judy reasons that a new Kitchen Maid will do just as well for her. How do the following facts bear on Judy's conclusion? Judy buys the same model dishwasher as Jasper's.