 This point reveals an important caveat: measures of happiness could correlate well with how happy people are, thus telling us which groups of people tend to be happier, while being completely wrong about absolute levels of happiness. Self-reports of happiness, for instance, might correctly indicate that unemployed people are considerably less happy than those with jobs. But every one of those reports could be wrong, say if everyone is unhappy yet claims to be happy, or vice-versa, so long as the unemployed report lower happiness than the employed. Similarly, bad thermometers may show that Minnesota is colder than Florida without giving the correct temperature.