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HSS welcomes applications from students who are interested in working full time toward a PhD in the social sciences.

All qualified applicants will be considered for admission to HSS's PhD program in the social sciences, which includes the fields of economics, political science, political economy, history, psychology, anthropology, law, and public policy. Admission to this program is highly competitive. The program is deliberately small and selective, with the admissions committee looking for students who demonstrate a commitment to scholarship, a willingness to work hard—as evidenced by letters of recommendation or other achievements—and expressed interests that align with those of the HSS faculty.

General Qualifications

Caltech requires that PhD applicants in any field be able to clearly express themselves in written and spoken English.

Modern approaches to the social sciences require the ability to think abstractly and quantitatively. As such, applicants must be skilled in formal reasoning. Although HSS does not require that an applicant's undergraduate degree be in any of the social sciences, the admissions committee expects every applicant to demonstrate a commitment to research in the social sciences. To be prepared to succeed in the social sciences PhD program, students should have a solid undergraduate background in mathematics, including at least:

  • two years of calculus, at the level of Apostol's Calculus, volumes 1 and 2; and
  • linear algebra, at the level of Apostol's Calculus, volume 2.

It is also strongly recommended that applicants complete an introductory course in mathematical statistics and real analysis before entering the HSS graduate programs.

Caltech requires applicants whose first or native language is not English to take the Test of English as a Foreign Language (TOEFL) as part of the application procedure. HSS is not accepting or considering Graduate Record Examination (GRE) scores from applicants to its PhD programs for Fall 2024 matriculation.

Financial Aid

Caltech offers competitive stipends in the forms of fellowships and research and teaching assistantships that are designed to cover tuition and living expenses. Students in good standing generally receive financial support for a maximum of five years. Funding for the summer quarters is not guaranteed; however, it may be provided based on the availability of such funding and on an individual student's performance. As a matter of educational policy, graduate students are expected to act as graduate teaching assistants at some point in their career.

Due to the full-time and research-intensive nature of the PhD programs in HSS, many students are also supported with research assistantships. Graduate students in all programs are also encouraged to apply for external fellowships.

Application Deadlines

To be considered for admission, a complete application, including all supporting material (including TOEFL scores), must be submitted to Caltech no later than December 15. Applicants are encouraged to submit their applications online through the Graduate Studies Office website.

If you have questions about the application process, please contact the option manager.

Bob Sherman talking to a student in Baxter hallway