Where PhDs get their Bachelors’ degrees

Last year I wrote about a study that looked at where CS PhD students got their bachelors’ degrees. Now Reed College has extended that question to other fields as well: Doctoral Degree Productivity.  Their point was to show how high Reed ranked on the standard they chose: the number of students who went on to get PhDs divided by the number of students getting bachelor’s degrees.  I quote the tables and accompanying text below, but I take no credit or blame for the data—this is directly from Reed’s site:

Undergraduate Origins of Doctoral Degrees

Percentage ranking of doctorates, by academic field, conferred upon graduates of listed institutions.

Rank	All Disciplines	Science and Math	Social Sciences	Humanities and Arts
1	Calif. Inst. of Tech.	Calif. Inst. of Tech.	Swarthmore	New England Conserv. of Music
2	Harvey Mudd	Harvey Mudd	Grinnell	Curtis Institute of Music
3	Swarthmore	Reed	Reed	Juilliard
4	Reed	MIT	Bryn Mawr	Cleveland Inst. of Music
5	Carleton	NM Institute Mining & Tech.	Spelman	St. John’s College
6	MIT	Carleton	Oberlin	Reed
7	Grinnell	Wabash	Wesleyan	Hellenic College-Holy Cross Greek Orthodox Sch. of Theology
8	Princeton	Rice	St. Joseph Seminary	Swarthmore
9	Harvard	Univ. of Chicago	Harvard	Oberlin
10	Oberlin	Grinnell	Pomona	Amherst

Percentage Ranking by Specific Fields of Study

Rank	Life Sciences	Physical Sciences	Psychology	Other Social Sciences*	Humanities
1	Calif. Inst. of Tech.	Calif. Inst. of Tech.	Univ. Puerto Rico – Aguadilla	Swarthmore	St. John’s, MD
2	Reed	Harvey Mudd	Wellesley	Reed	Reed
3	Swarthmore	Reed	Vassar	Harvard	Amherst
4	Carleton	MIT	Hendrix	Grinnell	Swarthmore
5	Grinnell	NM Institute Mining/Tech.	Pontifical Coll. Josephinum	Univ. of Chicago	Carleton
6	Harvey Mudd	Carleton	Grinnell	Bryn Mawr	Yale
7	Univ. of Chicago	Wabash	Swarthmore	Thomas More College of Lib. Arts	Thomas More College of Lib. Arts
8	Haverford	Rice	Barnard	Oberlin	Bryn Mawr
9	MIT	Univ. of Chicago	St. Joseph Seminary Coll.	Bard College at Simon’s Rock	St. John’s, NM
10	Earlham	Grinnell	Pomona	Wesleyan	Wesleyan
11	Harvard	Haverford	Reed	Amherst	Princeton
12	Cornell Univ.	Swarthmore	Wesleyan	Pomona	Bard College at Simon’s Rock

*Does not include psychology, education, or communications and librarianship.

Source: National Science Foundation and Integrated Postsecondary Education Data System. The listing shows the top institutions in the nation ranked by estimated percentage of graduates who went on to earn a doctoral degree in selected disciplines between 2001-2010.

All the schools listed are private schools except Univ. Puerto Rico—Aguadilla and NM Institute Mining/Tech., but seeing dominance by expensive private schools is not very surprising—grad school is expensive, and students who can afford expensive private schools are more likely to be able to afford expensive grad school and are less likely to need to work immediately after getting their B.S. or B.A. A PhD is not a working-class degree—it is prepares one for only a small number of jobs, mainly in academia or national labs, so for many it is just an elite status symbol.  What is more surprising is how poorly the Ivy League schools do on this list—perhaps those who get their elite status conferred by their bachelor’s institution see no need to continue on to get higher degrees.

Reed does not report numbers directly comparable with the ones in the Computing Research Association report, which reports only on computer science PhDs, where

Only one institution (MIT) had an annual average production of 15 or more undergraduates.   Three other institutions (Berkeley, CMU, and Cornell) had an average production of more than 10 but less than 15.  Together, these four baccalaureate institutions accounted for over 10% of all Ph.D.’s awarded to domestic students.   The next 10% of all Ph.D.’s in that period came from only eight other baccalaureate institutions (Harvard, Brigham Young, Stanford, UT Austin, UIUC, Princeton, University of Michigan, and UCLA). 

Note that five of the top producers of bachelor’s in CS who went on to get PhDs were public schools.  The CRA does not report PhD/BS numbers for individual institutions, probably because the numbers are too small to be meaningful for most colleges—you have to aggregate either across many colleges or across many fields before the denominators are big enough to avoid just reporting noise.  Reed did the aggregating across fields, while the CRA report aggregated across colleges, finding that research universities sent about 2.5% of their CS graduates on to get PhDs, 4-year colleges about 0.9% and masters-granting institutions about 0.6%.  They did have one finding that supports Reed’s analysis:

The top 25 liberal arts colleges (using the U.S. News and World Reports ranking) collectively enroll slightly less than 50,000 students per year in all majors and were the origins of 190 Ph.D. degrees between 2000 and 2010, collectively ranking ahead of any single research university.

Reed’s findings are also consistent with the NSF report that put the “Oberlin 50” colleges highest at over 5% of their science and engineering graduates going on to get PhDs, compared to about 3% for research universities.  The NSF report supports somewhat the analysis that socio-economic status is important in determining who goes on to grad school—private research universities match the Oberlin 50, but public research universities have only about half as large a fraction of their graduates go on to grad school.

I found out about this site from The Colleges Where PhD’s Get Their Start, which has a copy of the tables that probably came from an earlier, buggy  version of the site, because Lynn O’Shaughnessy wrote

I bet most families assume that attending a public flagship university or a nationally known private research university is the best ticket to graduate school. If you look at the following lists of the most successful PhD feeder schools for different majors, you will see a somewhat different story. Not a single public university makes any of the lists. The entire Cal State system, however, is considered the No. 1 producer of humanities PhD’s.

I could believe that the Cal State system had the largest raw numbers of students going on to get PhDs in humanities, as they are a huge 4-year college, enrolling about 438,000 students [http://www.calstate.edu/as/cyr/cyr13-14/table01.shtml], with about 76,000 bachelor’s degrees per year [http://www.calstate.edu/PA/2013Facts/degrees.shtml]. Are there any other colleges in the US graduating so many BS or BA students per year? But the fact remains that Cal State is not the flagship university of California, and the University of California probably has a much higher percentage of its alumni go on to get PhDs.

In fact, one of the big problems with these lists is the question of scale—most of the colleges that come up high on Reed’s lists (which means high on NSF’s lists) do so by having very small denominators—they don’t graduate many students, though a high percentage of those go on to get PhDs.  In terms of raw numbers of students who go on to get PhDs, the public research universities produce many more than the private research universities, and the liberal arts schools are just a drop in the bucket. Of the top 25 schools in terms of raw numbers who go on to get PhDs in science and engineering, 19 are public research universities and 6 are private research universities—of the top 50 only 17 are private research universities.

When you are looking for a cohort of similarly minded students, you get slightly higher enrichment at some very selective private schools, but there are actually more peers at a large public research university—if you can find them.