Monday, January 14, 2013

First the Facts

Today's guest blogger is Annika Peter.

I am a dark-matter and gravitational-dynamics junkie, currently finishing up a postdoctoral position at UC Irvine, and moving to a faculty position in the Departments of Physics and Astronomy at The Ohio State University. My husband is also an astrophysicist, currently a professor of astrophysics at Caltech. He is taking a professorship at OSU, too, so we have successfully found an excellent solution to our two-body problem! My two favorite aspects of my job are thinking deeply about and trying to solve some of the major mysteries of the universe, and working with undergraduate and graduate students. I am also a practical problem solver, which means I spend some time scheming about how to improve the scientific enterprise and university education.

Before jumping into a discussion of women in science, I thought it would be useful to provide some references and numbers. Not only do I think that these data are good for anyone in our field to be familiar with, but it will be a good jumping off point for some of my future posts.

Participation of women in physics and astronomy in an academic setting: We all know that there are few women in physics and astronomy, but what does “few” mean? There are several good databases with numbers on this subject. The first place I would recommend looking is the NSF, which maintains a set of tables on graduates and employment by field, sex, disability, race and ethnicity, citizenship, and year. The American Astronomical Association’s Committee on the Status of Women maintains an extensive set of links to various studies and informational resources. The American Physical Society has some useful information on its website.


Here I will describe some of the findings from a 2005 report by the American Institute of Physics (AIP) on women academics in physics and astronomy in the United States. Note that the AIP also maintains statistics and links to demographics in other countries, which you can find here.

Now, onto the 2005 AIP report (PDF):

•The proportion of women in physics and astronomy has been increasing with time at all levels (undergrad through full professor). As of 2003, 46% of bachelor’s degrees in astronomy and 22% in physics were going to women. At the PhD level, the numbers were 26% and 18% respectively. By contrast, in the year I was born (1982), the numbers were 20%, 10%, 15%, and 5%, respectively. Even in my lifetime, the proportion of women getting degrees in physics and astronomy has more than doubled. We have come a long way!

•In astronomy, 10% of full, and 23% of associate and assistant professors were women in 2003. In physics, 5% of full, 11% of associate, and 16% of assistant professors were women in 2002.

•The AIP estimated how many women one would expect at each career level given the time at which the typical person at that career stage would have finished college or graduate school. The numbers suggest that the proportion of women one would expect at a given career stage roughly matches what one would have expected given the gender split of their undergraduate and graduate cohorts, although there are some nuances to the data.

•This implies that one of the main reasons that physics and astronomy faculty have so few women is because those departments are OLD. Only ~5-10% of full professors in physics and astronomy are women today because only a few women were granted PhDs in these fields thirty or forty years ago. An interesting exercise is to count how many faculty members in your department are AARP eligible. As older generations retire and more recently minted PhDs get hired, the proportion of women in the faculty should creep up if departments hire women at the same proportion as they are obtaining PhDs. However, we will not achieve gender parity among the faculty until we achieve gender parity in the graduate student population, and even then there is likely to be a lag time unless future women graduates are significantly more awesome than the men.

•The participation of women in the faculty of physics and astronomy departments is proportionally lower at institutions that grant PhDs than institutions that grant only bachelor’s or master’s degrees. Unfortunately, the AIP report does not parse the numbers by faculty rank (lecturer, assistant, associate, full), which I think would have been illuminating. Without these data, it is difficult to tell if the PhD-granting institutions (the institutions that we often view as most prestigious) select against women or if their departments are simply much older.

•In my opinion, the most depressing thing about this report is its findings about the severe underrepresentation of women from ethnic and racial minorities in physics and astronomy. One statistic that particularly stands out in my mind is that only 35 PhDs in physics went to African-American women between 1976 and 2003.

Leaky pipeline: If you take the AIP study at face value, the major leak in the pipeline of women into academic physics and astronomy careers occurs at the undergraduate level. The AIP finds that almost half of the students who take high-school physics are women, yet women are only one in five of bachelor’s degree holders in physics. They also find that a far lower proportion of girls take the AP physics tests than they take physics classes in high school. This indicates the potential importance of interventions with high-school girls and undergraduate women.

If you look at the AIP numbers as well as some other studies, some other leaks (or selection pressures) begin to appear. First, it appears there is gap between college graduates and PhD holders in physics and astronomy among American women. The AIP suggests that the reason there appears not to be a leak between undergraduate studies and graduate school is the influx of women from other countries into American graduate programs.

Second, there appear to be bigger leaks in the astronomy pipeline at later stages for women than in physics, although this is largely going from undergraduates to graduate students.

Third, at the faculty level there appears to be a strong selection pressure for childless and/or single women in the natural sciences. Thus, even if the pipeline for women is not as so leaky going from graduate school to full professor, the women who stay in academia have very different family structures than men, with one study finding that women who have children as postdocs are far less likely to end up in tenured faculty positions than women or men with any other family structure.

Here is the link to that particular study.
Unfortunately, that study does not parse their findings by field, so it is unclear how much the family structures of women in physics and astronomy differ from women in the natural sciences as a whole. There are also studies on tenure rates as a function of family structure (see, e.g., this document [PDF]), but I have not seen studies from the past couple of years, after policies have been instituted at many top-tier universities to recruit and retain more women faculty, such as to slow the tenure clock for both men and women who become parents as junior faculty.

A study by the National Academies indicates that the structure of leaks in the pipeline varies significantly by field of study. For example, in biology, more than half of all undergraduate degrees go to women, but women only make up 35% of assistant professors. The life sciences pipeline is leaky after the undergraduate stage, in contrast to physics where the leaks largely occur very early.

In the second part of this post I'll examine some additional leaks in the pipeline, and thereafter I'll delve into the roles of women in science and solutions to fixing the pipeline in order to achieve gender parity in (astro)physics.

1 comment:

Ed Bertschinger said...

Thanks for the excellent summary.

The large drop in percentage of female physics undergraduates compared with high school students taking physics can be significantly influenced by the departmental climate for undergraduates. The percentage of physics bachelors degrees going to women among the top 10 departments (from the US News and World Report Graduate School rankings) ranges from under 10% to over 30% (source: IPEDS 2007-2011). The difference is statistically highly significant. Departments with a more supportive climate for students graduate a larger percentage of women and all of the students are happier. Conclusion: significant gains remain to be made by improvements at the undergraduate level.