greater and greater precision. Table 2 tells us that on any given occa -
sion, whether a person average in warmth will smile or not is a coin
toss. But it also tells us that we know with great precision that, in thelong run, that person will smile about half the time. And since, as wewill see, traits endure for long periods of time, their ability to predictlong-term patterns of behavior is extraordinary .
In the short run, though, it is helpful to know how useful traits are
in the real world, not the hypothetical distribution in Table 2. Fleeson(2001) has recently reported some interesting data relevant to thatquestion. He asked a group of college students to record on a Palm Pilothow they had been behaving in the past hour—how talkative, hard-working, or cooperative they had been. They repeated this process fivetimes a day for 2 weeks. He had two major findings: First, there wasabout as much variation within each person as there was between peo -
ple—each person tended to show a wide distribution of talkativeness,
hard work, and cooperation from time to time. Second, if half the rat -
ings were averaged, they predicted the average of the other half almost
perfectly . In other words, each individual had a characteristic meanlevel, but all people varied around that mean under different circum -
stances. Summer is always hot and winter cold, but there is a wide range
of temperatures within each season.
Bypatterns of thoughts, feelings, and actions— to return to our defi -
nition of traits—we mean to indicate both the breadth and the general -
ity of traits. Traits should be distinguished from mere habits: repetitive,
mechanical behaviors such as smoking or driving fast or saying “Youknow” after every sentence. Habits are specific learned behaviors; traitsA Trait Approach to Personality 27
TABLE 2. Hypothetical Distribution of Smiling Behavior at Different
Levels of Warmth
Smiles at stranger?
Level of warmth Total subjects Yes No Percentage smiling
Very high 70 63 7 90
High 240 168 72 70Average 380 190 190 50Low 240 72 168 30Very low 70 7 63 10
Note. Adapted from Costa and McCrae (1998b).