Mark Díaz is a Research Scientist with the Technology, AI, Society, and Culture (TASC) team in Responsible AI. His primary research investigates sociotechnical AI evaluation and documentation, including understanding data annotation and subjective disagreements related to differences in social context and experience. He has most recently begun work on the impacts of anthropomorphic generative AI on user perceptions and what those impacts mean for responsible AI practice. Mark completed his Ph.D. in Technology & Social Behavior, a joint program in Computer Science and Communication at Northwestern University where he was advised by Darren Gergle. Before completing his doctoral work on age-related biases in sentiment analysis, he worked as a graduate fellow at SMART Chicago, a nonprofit focused on technology access and equity in Chicago. As a graduate fellow he researched perceptions among Black and low-income Chicago residents of city technology policy.