Rankings of doctoral programs in the sciences published in 2018 were based solely on the results of surveys sent to academic officials in fall 2013 and fall 2017 in biological sciences, chemistry, computer science, earth sciences, mathematics, physics and statistics.
The individuals rated the quality of the program at each institution on a scale of 1 (marginal) to 5 (outstanding). Those who were unfamiliar with a particular school’s programs were asked to select “don’t know.”
The schools with the highest average scores among those who rated them were sorted in descending order and appear in the rankings tables. Survey results from fall 2013 and fall 2017 were averaged to compute the scores; programs needed at least 10 ratings to be ranked. Ipsos Public Affairs conducted all doctoral surveys.
The universe of schools surveyed in biological sciences, chemistry, computer science, earth sciences, mathematics and physics consisted of schools that awarded at least five doctoral degrees for the years from 2011 through 2015, according to the National Science Foundation report, “Survey of Earned Doctorates.”
The American Statistical Association provided U.S. News with eligible programs for statistics.
In biological sciences, graduate programs may be offered in a university’s medical school or its college of arts and sciences. In statistics, graduate programs may be offered through a biostatistics or statistics department.
Questionnaires were sent to the department heads and directors of graduate studies at each program in each discipline.
The following are the number of schools surveyed: biological sciences, 275; chemistry, 205; computer science, 188; earth sciences, 124; mathematics, 181; physics, 184; and statistics, 109.
In the doctoral sciences rankings, programs with an average peer assessment score equal to or greater than 2.0 are numerically ranked. U.S. News lists all those with average peer assessment scores of less than 2.0 in alphabetical order as Rank Not Published, or RNP. Doctoral programs receiving less than a total of 10 ratings after combining the results from both the 2013 and the 2017 surveys are listed as unranked.
Specialty rankings of doctoral science programs are based solely on nominations by department heads and directors of graduate studies at peer schools. These respondents ranked up to 10 programs in each area. Those with the most votes appear in the rankings tables.
Schools in the specialty rankings are numerically ranked in descending order based solely on the number of nominations they received, as long as the school or program received seven or more nominations in that specialty area. This means that schools ranked at the bottom of each specialty ranking received at least seven nominations.
Rank Not Published means that U.S. News calculated a numerical rank for a school or program but decided for editorial reasons not to publish the rank.
U.S. News will supply schools or programs listed as Rank Not Published with their numerical ranks if they submit a request following the procedures listed in the Information for School Officials.