> For instance, he says, if you notice that a Chinese restaurant in your neighborhood is always half-empty, and a nearby Indian restaurant is always crowded, then information about what percentages of people prefer Chinese or Indian food will tell you which restaurant, if either, is of above-average or below-average quality.<p>The situation described here wouldn't tell you anything about the quality of the restaurants. It <i>might</i> tell you what kind of food that neighborhood prefers. It <i>might</i> tell you which restaurant is more affordable. It <i>might</i> tell you which restaurant has a better public image. Or maybe it just tells you which restaurant is renting out its parking lot to a nearby car repair shop. To wit, quality cannot be determined by observing human behavior. Quality is determined exclusively by predefined parameters. Loudness, brightness, velocity, purity, etc., are measures of quality. In other words, quality is antipodal to popularity. Every human relation to an object, such as cost, availability, relevance, etc., has priority over quality at all times. It is even more accurate to say that quality is never a direct factor in choice. A person does not choose a knife, for example, because it is sharper than other knives; a person chooses the knife because it is <i>sharp enough</i> to meet their needs and, more importantly, because it is accessible to them. The only exception is the case where a person seeks out the highest quality option for the sake of quality itself, i.e. "I want to find the sharpest knife in the world." In this exceptional scenario, however, one learns nothing by studying the quality-seeking crowd that could not have been learned by simply measuring and comparing objects, i.e. it is much easier to find the sharpest knife by measuring knives for sharpness than by trying to determine which humans buy knives strictly because they are sharper than the alternatives (in such a case you would still have to measure the knives to confirm any conclusions you came to). All of this being said, I can't believe people at MIT studying human behavior would make such an absurd analogy. It indicates a complete misunderstanding of not only human beings but of logic as well.