into high and low groups on each of these three variables, stability coef -
ficients for the five personality factors were essentially identical. There
are, of course, many other variables that have not yet been examined,but to date no psychological characteristic has been shown to moderatethe stability of personality traits.
Life Events
Perhaps a more likely candidate for a moderator of change is some ex -
ternal event that alters one’s life and thus one’s personality traits. Costa,
Herbst, and colleagues (2000) conducted exploratory analyses based onthis premise. In their large midlife study , they asked participants to re -
port which of 30 specific life events they had experienced in the past 6
years. Events included got married ,your parent died , and your spouse was
fired. Individual events were relatively rare in this sample, so an index of
total life events was created by summing across the 30 events. Contraryto the hypothesis, there was no evidence that more events led to morechange in personality traits from before the 6-year period to after it.
However, analyses of selected events did show small effects. A
small group of people (4% of the sample) were fired from a job; com-pared to the group of people who were promoted during the same pe-riod, these individuals increased in Neuroticism and decreased in Con-scientiousness. Again, women who were divorced became a bit higherin Extraversion and Openness compared to women who got married. Itremains to be seen how replicable these findings are and how enduringthe changes may be.
Neyer and Asendorpf (2001) recently examined changes over a 4-
year period in a sample of young German adults. It is well known thatthere are changes in the mean levels of personality traits in this develop -
mental era; what is not known is whether those changes are a natural
and more or less inevitable effect of aging itself or whether they resultfrom the social changes that come with adult roles of work and family .Neyer and Asendorpf hypothesized that settling down with a life part -
ner would enhance emotional maturity and lead to lower Neuroticism,
and that having a child would make individuals more responsible andthus higher in Conscientiousness.
Over the 4 years of their study , some participants remained single
whereas others who were initially single became involved in a stable re -
lationship. Consistent with hypotheses, those who remained single did130 PERSONALITY IN ADULTHOOD