Child Development

Publications by Bayley
‘‘Mental Growth during the First Three Years: A Developmental
Study of Sixty-One Children by Repeated Tests.’’ Genetic Psy-
chology Monographs 38 (1933):1–38.
Studies in the Development of Young Children. Berkeley: University of
California Press, 1940.
‘‘On the Growth of Intelligence.’’ American Psychologist 10
(1955):805–818.
‘‘Implicit and Explicit Values in Science as Related to Human
Growth and Development.’’ Merrill-Palmer Quarterly 2
(1956):121–126.
‘‘Value and Limitations of Infant Testing.’’ Children 5 (1958):129–
133.
‘‘The Accurate Prediction of Growth and Adult Height.’’ Modern
Problems in Paediatrics 7 (1962):234–255.
‘‘Research in Child Development: A Longitudinal Perspective.’’
Merrill-Palmer Quarterly 11 (1965):183–208.
‘‘Behavioral Correlates of Mental Growth: Birth to Thirty-Six
Years.’’ American Psychologist 23 (1968):1–17.

Tracy L. Smith

BEHAVIOR ANALYSIS

Behavior analysis is the scientific study of how a spe-
cific observable (and therefore measurable) behavior
is related to specific observable events in the environ-
ment of that behavior—events (changes in the envi-
ronment) that are antecedent (prior) to and those
that are consequent to the behavior in question. The
behavior of all living organisms is continuously and
lawfully influenced (changed) by its consequences:
Some increase and others decrease the probability of
every response. Hence, the unique physical and social
environment of an infant develops a unique person
by selecting (strengthening) some behaviors (motor,
verbal, and emotional) in certain situations and ig-
noring or punishing (weakening) others. In this con-
tinuous process of selection by consequences, every
new skill encounters new features of the environment.
Consequently, every person has some behaviors simi-
lar to those of everyone else and some that are differ-
ent from anyone else. Behavior analysis is used to
improve behavior by altering the environment.

See also: SKINNER, B. F.; THEORIES OF
DEVELOPMENT

Bibliography
Bijou, Sidney W., and Donald M. Baer. Child Development, Vol. 1:
A Systematic and Empirical Theory. New York: Appleton-
Century-Crofts, 1961.
Skinner, B. F. ‘‘Selection by Consequences.’’ Science 213
(1981):501–504.

Don Bushell Jr.

BELL CURVE

In 1835 Belgian statistician and astronomer Lambert

Quételet suggested applying statistical probabilities

to quantitative trait differences between individuals.

The resulting Bell Curve, a bilateral graphic with tails

resembling a bell’s rim, served to compare individual

characteristics against those of a group. In 1869 Fran-

cis Galton (supporter of Darwin’s evolutionary theo-

ry) extended the meaning of the graph to include the

measurement of natural ability in addition to other

traits. It reflects distributions of most normally devel-

oped human physical, intellectual, and personality

traits, designating a probable frequency for each

value of the trait. The average of a set of values be-

comes the distribution mean, located midpoint in this

graphic. Valuable in psychological testing, comparing

individuals’ abilities relative to others may suggest

relevant outcomes such as need for special education-

al treatment. Some genetics-oriented researchers

have generated controversy by applying Bell Curves

to intelligence data collected on racial groups. Ques-

tionable assumptions about intellectual inferiority

among some races leads to flawed educational treat-

ments, impeding ability development for specific

groups.

See also: DEVELOPMENTAL NORMS; INTELLIGENCE

Bibliography

Anastasi, Anne. Psychological Testing, 5th edition. New York:

Macmillan, 1982.

Herrnstein, Richard J., and Charles Murray. The Bell Curve: Intelli-

gence and Class Structure in American Life. New York: Free Press,

1994.

Patricia A. Haensly

BILINGUAL EDUCATION

Bilingual education programs in schools aim to teach

students to listen, comprehend, speak, read, and

write in a language other than their native tongue.

This is done most effectively when use of their prima-

ry language is encouraged as well. Students in bilin-

gual classes acquire greater skills and acquire them

more quickly when they continue to practice both lan-

guages. This also increases their effectiveness in the

other core classroom subjects and helps them to de-

velop social competencies. A language may be ac-

quired by being in the environment where the

language is spoken and participating in that cultural

setting, or it may be learned in a classroom with field

techniques that allow practice in the new language.

Therefore, one goal of bilingual education is to create

an environment where students and their cultures are

fully supported.

50 BEHAVIOR ANALYSIS