Socioeconomic status (SES) is a key covariate in analyses by the Programme for International Student Assessment (PISA). In its technical documentation, PISA offers evidence for the Economic, Social, and Cultural Status instrument (ESCS) as a valid measure of SES. This dissertation, however, offers both conceptual and empirical arguments that ESCS does not meet the realist and pragmatic requirements set forth by modern measurement and validity theories. I further demonstrate how the adoption of non-measurement models in ESCS has undermined the trustworthiness of PISA's most recent headline findings. Finally, I offer guidance for improving the validity of SES measurement in future PISA cycles. Use was made of the computational facilities administered by the Center for Scientific Computing at the CNSI and MRL (an NSF MRSEC; DMR-1720256) and purchased through NSF CNS-1725797. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtmlTest.]
