Caltech NAS Rankings
In 2006-7, the National Research Council (NRC) of the National Academy of Sciences conducted a comprehensive survey of more than 5000 research-based doctorate programs in 212 schools and 62 fields. Details of the methodology, data, and a detailed statistical analysis (available in spreadsheet format) are available. The statistical analysis evaluates programs on 20 measures compiled from objective data as well as surveys of faculty. In addition to quantitative measures of factors such as research productivity, two rankings are assigned to every program. The "S" (survey-based) ranking is based on a survey of peer faculty of the importance of the general characteristics of doctoral programs. The "R" (regression-based) ranking is based on ratings given by peer faculty to a sample of programs. Rather than give a unique rank for each program, the 5 and 95 percentile level values are provided for both the R and S rankings.
The NRC explanation for not giving a single ranking was that "The committee felt strongly that assigning to each program a single number and ranking them accordingly would be misleading, since there are significant uncertainties and variability in any ranking process. Uncertainties arise from assumptions made in creating a ranking model based on quantitative data on program characteristics. Even with such a model, variability arises from numerous sources, including differences in the views among the faculty surveyed, fluctuations in data from year to year, and the error inherent in estimations from any statistical model. The ranges reflect some of this uncertainty and variability." The consequence is that every school and program will interpret the data differently.
Interpreting Caltech's Rankings
Despite the ambiguity of the rankings, all of the 24 ranked graduate programs at Caltech have placed exceptionally high in this survey and validate our approach to graduate education. There are many different ways that we can compare our performance with other Institutions. It is important in doing so that we not use the raw rankings but our relative standing taking into account the small size of some of our programs.
Here are a half-dozen ways to look at the rankings of our programs within their field and size group.
- 23 of the 24 graduate programs are ranked within the top four programs in the nation in their size quartile as determined by the R95 ranking.
- 23 of the 24 graduate programs are ranked within the top four programs in the nation in their size quartile as determined by the S95 ranking.
- Programs that are ranked in the top five nationally based on R95, irrespective of size: Aeronautics, Astrophysics, Biology, Chemical Engineering, Chemistry, Geology, Geophysics, Materials Science, Planetary Science, and Physics.
- Programs that are ranked in the top five nationally based on S95, irrespective of size: Aeronautics, Applied Mechanics, Astrophysics, Bioengineering, Biology, Biochemistry and Molecular Biophysics, Chemical Engineering, Chemistry, Civil Engineering, Electrical Engineering, Environmental Science and Engineering, and Materials Science.
- For the smaller programs, it is more realistic to look at the placement within the same size quartile, or smaller, rather than the entire set of programs.
- All of the following programs (1st or 2nd quartile) are in the top three nationally in the R95 ranking: Aeronautics, Applied and Computational Mathematics, Astrophysics, Bioengineering, Civil Engineering, Computer Science, Geochemistry, Geology, Mathematics, Planetary Science, and Social Science (Economics).
- All of the following programs (1st or 2nd quartile) are in the top two nationally in the S95 ranking: Aeronautics, Applied Mechanics, Astrophysics, Bioengineering, Civil Engineering, Computer Science, Geochemistry, Geology, Mathematics, Planetary Science, and Social Science (Economics).
- Programs that are placed within the top 10% of all size programs in that field based on an average of the R95 and S95 rank order are: Aeronautics, Astrophysics, Biochemistry and Molecular Biophysics, Bioengineering, Biology, Chemical Engineering, Chemistry, Electrical Engineering, Environmental Science and Engineering, Geology, Geophysics, Materials Science, Physics, Planetary Science, and Social Science (Economics).
These six different ways of looking at the rankings cover all the graduate programs in the Institute. There are many other ways to look at this data but it is clear that Caltech's graduate programs are ranked among the best in the nation and in many cases, at the top of their field.
14 October 2010