Encyclopedia of Sociology

COHORT PERSPECTIVES

Kruglanski, eds., The Social Psychology of Knowledge.

Cambridge, Eng.: Cambridge University Press.

TODD D. NELSON

COGNITIVE DISSONANCE
THEORY

See Cognitive Consistency Theories; Social
Psychology.

COHABITATION

See Alternative Life-Styles; Courtship.

COHORT ANALYSIS

See Cohort Perspectives; Longitudinal Research;
Quasi-Experimental Research Design.

COHORT PERSPECTIVES

The birth cohort, or set of people born in approxi-
mately the same period of time, has a triple refer-
ence as an analytical tool in sociology: (1) to co-
horts of people who are aging and succeeding each
other in particular eras of history; (2) to the age
composition of the population and its changes; and
(3) to the interplay between cohorts of people and
the age-differentiated roles and structures of society.
Diverse sociological studies illustrate the use of
these cohort perspectives (i.e., both theoretical
and empirical approaches) to investigate varied
aspects of aging and cohort succession, popula-
tion composition, and the reciprocal relationships
between cohorts and social structures.

CONCEPTUAL FRAMEWORK

Figure 1 is a rough schematization of the major
conceptual elements implicated in these interre-
lated cohort perspectives as they have relevance
for sociology (for an overview, see Riley, Johnson,
and Foner 1972; Riley, Foner and Riley 1999).

Aging and Cohort Succession. The diagonal
bars represent cohorts of people born at particular

time periods who are aging from birth to death—

that is, moving across time and upward with age.

As they age, the people in each cohort are chang-

ing socially and psychologically as well as biologi-

cally; they are actively participating with other

people; and they are accumulating knowledge,

attitudes, and experiences. The series of diagonal

bars (as in the selected cohorts A, B, and C) denote

how successive cohorts of people are continually

being born, grow older through different eras of

time, and eventually die.

Age Composition of the Population. The per-

pendicular lines direct attention to the people si-

multaneously alive in the society at particular dates.

A single cross-sectional slice through the many

coexisting cohorts (as in 1990) demonstrates how

people who differ in cohort membership also

differ in age—they are stratified by age from the

youngest at the bottom to the oldest at the top.

Over time, while society moves through historical

events and changes, this vertical line should be

seen as moving across the space from one period

to the next. At different time periods the people in

particular age strata are no longer the same peo-

ple; inevitably, they have been replaced by young-

er entrants from more recent cohorts with more

recent life experiences.

Cohorts and Social Structures. Correspond-

ing to the age strata in the population, the perpen-

dicular lines also denote the age-related role op-

portunities and normative expectations available

in the various social structures (e.g., in schools for

the young, in work organizations for those in the

middle years, in nursing homes for the old, in

families for all ages, etc.). People and structures

are interdependent: changes in one influence

changes in the other. Yet the two are often out of

alignment, causing problems for both individuals

and society.

This three-fold heuristic schematization, though

highly oversimplified, aids interpretation and de-

sign of sociological work that takes cohort per-

spectives into account. (For simplicity, the discus-

sion is limited here to cohorts in the larger society,

with entry into the system indexed by date of birth.

Parallel conceptualization refers also to studies of

cohorts entering other systems, such as hospitals,

with entry indexed by date of admission, or the

community of scientists, with entry indexed by

date of the doctoral degree—e.g., Zuckerman and