T H E J O U R N A L O F H U M A N R E S O U R C E S • 46 • 3
The Phantom Gender Difference in the College Wage Premium
William H. J. Hubbard
A B S T R A C T
A growing literature seeks to explain why so many more women than men now attend college. A commonly cited stylized fact is that the college wage
premium is, and has been, higher for women than for men. After identify- ing and correcting a bias in estimates of college wage premiums, I find
that there has been essentially no gender difference in the college wage premium for at least a decade. A similar pattern appears in quantile wage
regressions and for advanced degree wage premiums.
I. Introduction
Today in the United States, more women than men attend and gradu- ate from college, a dramatic change from recent decades. This development has
spawned a growing literature that attempts to identify its causes. See Chiappori, Iyigun, and Weiss 2009; Goldin, Katz, and Kuziemko 2006; DiPrete and Buch-
mann 2006; Dougherty 2005. Perhaps the most prominent stylized fact in this literature has been that the college wage premium for women is higher than the
college wage premium for men and has been for at least 40 years.
1
This stylized fact has framed the discussion in this literature: a higher return to education for women explains why more women than men attend college today, but
it leaves unanswered why more men attended college in the past since the college wage premium was higher for women in the past as well. Hence, some scholars
1. The college wage premium is generally defined, and I define it here, as the difference in log wages between college graduates and high school graduates with no college education.
William H.J. Hubbard is the Kauffman Legal Research Fellow at the University of Chicago Law School and a Ph.D. Candidate in the University of Chicago Economics Department. He is grateful for com-
ments from Gary Becker, Pierre-Andre Chiappori, Jonathan Hall, Devon Haskell, Ethan Lieber, Lee Lockwood, Kevin Murphy, Derek Neal, Emily Oster, Genevieve Pham-Kanter, Mark Phillips, Jesse Sha-
piro, Hugo Sonnenschein, Andrew Zuppann, and participants in the Workshop in Applications of Eco- nomics at the University of Chicago. The data used in this article can be obtained beginning six months
after publication through three years hence from William H. J. Hubbard, University of Chicago Law School, 1111 E. 60th Street, Chicago, IL 60637, or by email at whubbarduchicago.edu.
[Submitted December 2009; accepted July 2010] ISSN 022-166X E-ISSN 1548-8004 䉷 2011 by the Board of Regents of the University of Wisconsin System
Hubbard 569
have looked to factors that prevented women in the past from exploiting the higher college wage premium for women. Goldin, Katz, and Kuziemko 2006 point to past
barriers to women’s education and careers; as these barriers fell, the gender differ- ence in the college wage premium became decisive: “According to most estimates,
the college log or percentage wage premium is actually higher for women than men, and it has been for some time. . . . As the labor force participation of women
has begun to resemble men’s, women have responded to the monetary returns.” Analogously, Chiappori, Iyigun, and Weiss 2009 combine an exogenous fall in the
time required for housework and “the higher labor-market return to schooling for women” to explain the relative rise in women’s college attainment.
But what if this stylized fact, the starting point for these arguments, is wrong? I will argue that the college wage premium for women is not larger for women than
men, and we must revisit our accounts of the dramatic rise in women’s college attainment relative to men. Most recent estimates rely on Current Population Survey
CPS wage data that are “topcoded” or censored at a maximum value. Topcoding biases estimates of the college wage premium downward for males relative to fe-
males, and the magnitude of this bias has grown over time. Once I account for this bias, I find no gender difference in the college wage premium in recent years.
This paper proceeds as follows. Section II briefly discusses recent estimates of the college wage premiums for men and women. None of these estimates adequately
accounts for the bias caused by censoring. Section III presents facts on topcoding and shows how topcoding can bias estimates of the college wage premium. Section
IV describes the data set I use in my estimates. In Section V, I reestimate college wage premiums for men and women using CPS data after accounting for topcodes,
and show that the college wage premium is not larger for women than for men, at least in recent years. Section VI concludes.
II. Existing Estimates
