The Psychology of Friendship - Oxford University Press (2016)

28 Friendship Across the Life Span

sample age younger than 30 years) observed increases in the size of friendship net-
works, whereas studies with older adults (mean sample age older than 65  years)
observed decreases in the size of friendship networks (no suitable longitudinal
studies were available for middle adulthood). Since family networks did not change
significantly in size across the life span (cross- sectionally and longitudinally; Wrzus
et al., 2013), the observed changes in personal and global networks may be attribut-
able to the observed changes in friendship networks.
Such normative changes are likely (at least in part) a result of normative life
events (for integrative reviews, see Neyer, Mund, Zimmermann, & Wrzus, 2014;
Wrzus et  al., 2013). During young adulthood, people enter new contexts, where
many people acquire new friends. For example, during the first months of college,
people form on average about 10 new friendships (Asendorpf & Wilpers, 1998).
When young adults enter the work force, they also establish new friendships (often

Decrease Increase

Lovell & Richey, 1995

Global

network

Personal

work

Friends

network

Perl, 1988

Milardo et al., 1983

Hays & Oxley, 1986

Dykstra et al., 2005

van Tilburg et al., 2002

van Tilburg et al., 1998

Ikkink & van Tilburg, 1999

Lang, 2000

Neyer & Lang, 2004

Morgan et al., 1996

McLaughlin et al., 2011

Neyer & Lang, 2004

Milardo et al., 1983

Neyer & Lang, 2004

Perl, 1988

Asendorpf, 2000

Aartsen et al., 2004

van Tilburg et al., 1998

Neyer & Lang, 2004

–1.1–0.9–0.7–0.5–0.3–0.10.1

Effect size (Cohen's d)

0.30.50.70.91.1

Older than 65 years

Younger than 30 years

Figure 2.1 Observed longitudinal changes in selected social relationship networks in
young (dark bars) and late adulthood (gray bars). Global networks consist of family
members, friends, coworkers, acquaintances, and others. Personal networks consist mainly
of family members and friends. Friend networks include only friends. Adapted from
Wrzus, C., Hänel, M., Wagner, J., & Neyer, F. J. (2013). Social network change and life
events across the lifespan: A meta- analysis. Psychological Bulletin, 139, 63. Copyright 2013
by the American Psychological Association.