shows these new criteria are uncorrelated to student performance among CS majors [ 5].

At the doctoral level, women’s representation has increased in all disciplines. The rate of increase has been greatest in the biological sciences, but only slightly slower in mathematics, chemistry, and astronomy. Women now earn approximately 40 percent of chemistry doctorates and more than 40 percent of astronomy doctorates.

The pattern of women’s representa-
tion in physics, engineering, and CS
There is considerable variation in
the success with which disciplines uti-
lize the pool of scholars they educate
by hiring them into faculty positions.

Figure 4 shows that CS, mathematics,
and physics—fields in which women
are comparatively less well-represent-
ed—are more successful at hiring
women PhDs for assistant professor-
ships than are astronomy, chemistry,
and biology—fields in which women
are better represented. However, in all
fields, women are more underrepre-
sented at higher faculty ranks [ 6].
These data, particularly the variabil-
ity in women’s representation among
recipients of bachelor’s degrees and
the extent to which their representa-
tion among PhDs is matched at the
rank of assistant professor, cast doubt
on the validity of several explanations
for women’s comparative lack of rep-
resentation in the physical sciences
and engineering. One common expla-
nation is that women are more inter-
ested in people than in things. While
this explanation might account for the
tremendous growth in women’s repre-
sentation in biology, it cannot explain
similar increases in chemistry and as-
tronomy [ 7]. An alternative explanation
claims women’s underrepresentation
in math-intensive physical sciences re-
sults from innate differences in men’s
and women’s mathematical abilities.
In the face of evidence that differences
between men’s and women’s math
scores on standardized tests have dis-
appeared as educational opportunities
have equalized [ 8], proponents of the in-
nate differences explanation argue that
while men and women on average have
similar math skills, there is greater
variability in men’s achievement scores
and there are more men among those
with the highest (and lowest) achieve-
ment scores in mathematics [ 9]. This
argument rests on the unsubstanti-
ated assumption that scientists and
engineers are predominantly drawn
from the small population of people
in “the far upper tail of the math abil-
ity distribution” [ 10]. Interestingly, the
difference in male variability in math-
ematics ability is narrowing in the U.S
and is entirely absent in several ethnic
groups and in some other countries
[ 11]. This suggests that social and cul-
tural factors rather than biological dif-
ferences are responsible. Indeed, the
data showing considerable increases in
women’s representation in many scien-
tific disciplines at all educational levels
and within the professoriate cannot
be attributed to sudden changes in in-
nate abilities since 1972 [ 12]. Rather, the
substantial changes in laws, attitudes
toward women and women’s roles, and
access to educational opportunities we
have witnessed since the early 1970s
have far more explanatory power.
Figure 1: Percentage of women receiving science and engineering degrees in the
U.S., 1966-2010.

Pe rc en t Wo men

0.6

Bachelors Masters PhD

0.5

0.4

0.3

0.2

0.1

0 196619681970197219741976197819801982198419861988199019921994199619982000200220042006200820102012

Source: National Science Foundation (NSF), National Center for Science and Engineering Statistics, IPEDS Completion Surveys (NSF population of institutions), 1966-2012, Integrated Science and Engineering Resources Data System ( WebCASPAR, https://webcaspar.nsf.gov).

P er ce nt Wom en

0.7

Biological Sciences

0.6

0.5

0.4

0.3

0.2

0.1

0
196619681970197219741976197819801982198419861988199019921994199619982000200220042006200820102012
Mathematics and Statistics Chemistry Physics
Astronomy Computer Science Engineering
Figure 2. Percentage of women receiving bachelor’s degrees in the U.S., selected
STEM disciplines, 1966-2012.

Source: NSF, WebCASPAR ( https://webcaspar.nsf.gov).