Sex-Related Comparisons: Observations 115TAKE HOME POINTS
■ Sex differences in math for the general population range
between small and zero and are decreasing over time.
■ Regardless of whether sex differences in math appear
on achievement tests, females outperform males in
school. Explanations for this paradox have to do with
the different orientations girls and boys have toward
schoolwork.
■ Sex differences in math ability among the highly talented
are substantial; these differences may relate to men’s
advantage in spatial skills, in particular mental rotation.Verbal Ability
Sex differences in verbal ability are among the
first cognitive abilities to be noticed (Halpern,
2000). On average, girls talk earlier than boys
and develop larger vocabularies and better
grammar than boys. Fourth-grade girls have
been shown to be better at reading than boys
across 33 countries (Mullis et al., 2003).
In an older meta-analysis of 165 stud-
ies that evaluated verbal ability, a very small
effect emerged (d=-.11), in the direction of
women outperforming men (Hyde & Linn,
1988). The investigators examined several
types of verbal ability, including vocabulary,
analogies, reading comprehension, and essay
writing. All the effect sizes were small, except
for speech production; in that case, there was
a moderate effect of female superior perfor-
mance (d=-.33). There was a trend for ar-
ticles whose first author was male to report
smaller effect sizes than articles whose first
author was female; this reminds us of the po-
tential for experimenter bias.
Sex differences were consistent across
age groups, from 5-year-olds to adults overhave a more performance-oriented style
(I do math to show my teacher I’m smarter
than the other students). In a study of fifth-
graders, sex differences in orientation pre-
dicted math grades 2 years later. They also
found that girls were less likely than boys to
be disruptive in class. The combination of
having a mastery orientation and being less
disruptive in the classroom was linked to
girls’ higher math grades.
Regardless of whether there are sex dif-
ferences in math aptitude, there is a clear sex
difference in attitudes toward math. Cross-
cultural research has shown that eighth-
grade males have more positive attitudes
toward math than females across 49 differ-
ent countries (Else-Quest et al., 2010). Males
are more self-confident (d=+.15) than
females and value math more than females
(d=+.10). In the United States the effect
sizes were .26 and .05. It is not clear whether
attitudes toward math have changed much
over time. In a U.S. Gallup Poll (2005), simi-
lar numbers of male and female teens (aged
13 to 17) said math is their favorite subject
(29%) but more girls than boys said that
math is their most difficult subject (44%
versus 31%).
It is possible that math ability is linked
to spatial ability, especially among those
who are highly talented in math. Math
achievement scores have been linked to
mental rotation ability (Nuttall, Casey, &
Pezaris, 2005). Math ability is an interest-
ing cognitive ability because it includes
both spatial and verbal skills. One study
showed that males performed better on
math problems that required spatial solu-
tions, whereas females performed better
on problems that required verbal solutions
and memory from textbooks (Gallagher,
Levin, & Cahalan, 2002).M04_HELG0185_04_SE_C04.indd 115 6/21/11 8:02 AM