Our Research
We seek to solve grand challenges through multi-disciplinary approaches, advancing science and improving society.
CMU Societal Computing Research
Embark on a transformative journey at the forefront of Societal Computing within Carnegie Mellon University's Software and Societal Systems Department (S3D). Our Societal Computing PhD program thrives at the intersection of technology and humanity, tackling critical challenges such as algorithmic fairness, privacy, security, and the ethics of AI through bold, interdisciplinary research.
Our distinguished faculty lead groundbreaking initiatives—from Dr. Riccardo Paccagnella’s revolutionary Hertzbleed research, uncovering vulnerabilities affecting billions of devices; to Dr. Nicolas Christin’s incisive analyses of cybersecurity economics, reshaping our understanding of digital safety; to Dr. Lorrie Faith Cranor’s pioneering work making privacy and security accessible and practical for everyone.
We are computer scientists pioneering society's frontier, driven equally by rigorous computational excellence and purposeful societal impact. Whether your expertise lies in technology, policy, ethics, or beyond, join us in harnessing technology to benefit society—where computing innovation drives meaningful, real-world change.
Research Areas
Faculty
Our distinguished faculty members are experts in their fields, guiding students in interdisciplinary research that tackles complex societal challenges. Meet a few!
Riccardo Paccagnella
Dr. Riccardo Paccagnella, Assistant Professor of Computer Science at Carnegie Mellon University, is a leader in system and hardware security. His work on the Hertzbleed attack, winner of the 2022 Pwnie Award for Best Cryptographic Attack, exposed critical vulnerabilities in widely-used Intel and AMD processors, prompting global security updates and reshaping assumptions about secure hardware design. PhD students interested in hardware security, cybersecurity, and the intersection of hardware and software design will thrive under Riccardo's mentorship, contributing to research that strengthens protections for billions of users worldwide.
Nicolas Christin
Nicolas Christin, Professor and Department Head at Carnegie Mellon's Software and Societal Systems Department, is a global expert in cybersecurity economics and online crime. His influential research on cryptocurrency risks and illicit markets like Silk Road shapes global technology policy and security analytics.
Students working with Nicolas will gain rigorous technical training and policy insights, preparing them to address critical societal challenges at the intersection of economics, cybersecurity, and technology.
Lorrie Faith Cranor
Lorrie Cranor, Bosch Distinguished Professor at Carnegie Mellon University, leads pioneering usable security and privacy research. As director of CyLab's Usable Privacy and Security Lab (CUPS), her work—spanning privacy policies, phishing prevention, and passwords—influences global standards protecting millions of users daily.
PhD students passionate about the intersection of security, privacy, and human behavior will thrive under Lorrie's mentorship, designing practical, user-centric technologies with real-world impact.
Hoda Heidari
Hoda Heidari, Assistant Professor at Carnegie Mellon University, advances the ethical design of artificial intelligence, focusing on fairness, accountability, and transparency. An award-winning researcher and co-leader of CMU's Responsible AI Initiative, she actively shapes the AI community through influential workshops and interdisciplinary collaboration. -- PhD students inspired to create socially responsible AI will benefit from Hoda's mentorship, bridging technical innovation and real-world societal impact.
Steven Wu
Steven Wu, Assistant Professor at Carnegie Mellon University, reimagines privacy-preserving technologies, fairness, and algorithmic equity. Recognized by prestigious awards from Amazon, Google, and Facebook, his research empowers students to address systemic inequities through human-centered algorithm design.
Under Steven's mentorship, PhD students will develop innovative solutions promoting fairness and privacy, driving meaningful societal impact across healthcare, public policy, and beyond.
Students
Our current PhD students are working on a variety of impactful projects that align with our research areas.
“A combined synchronization index for evaluating collective action social media”
Lynnette Ng’s groundbreaking research tackles the pressing challenge of distinguishing organic grassroots movements from bot-driven information campaigns on social media, where coordinated actions shape public discourse and can spark real-world protests. Her pioneering Combined Synchronization Index (CSI) offers a hierarchical approach, measuring user synchronicity across hashtags, URLs, and mentions, applied rigorously to six political and social activism events on X. The study reveals that human users typically exhibit higher synchronous scores than bots, providing a powerful framework to quantify and rank collective action while predicting potential offline impacts. This work excites readers by showcasing how computational social science can safeguard democratic discourse and enhance online integrity, offering tools for researchers, platform operators, and policymakers to proactively address manipulation in our digital age—a testament to S3D’s leadership at society’s frontier. Read more
“A Two-Decade Retrospective Analysis of a University's Vulnerability to Attacks Exploiting Reused Passwords”
(USENIX Security 2023, Distinguished Paper Award)
Alexandra Nisenoff’s award-winning research confronts the pervasive vulnerability of university accounts to credential-guessing attacks, exposing how password reuse across platforms endangers sensitive academic data over time. Through an unprecedented two-decade analysis, her team simulated attacks by matching usernames against hundreds of breach compilations, successfully guessing passwords for 32% of accounts linked to university emails in breaches and 6.5% with matching usernames. This methodologically rigorous study, honored with a Distinguished Paper Award at USENIX Security 2023, uncovers alarming long-term risks and patterns, urging a rethink of institutional security. Readers should be thrilled by its transformative implications—already influencing password policies and user education—demonstrating how Societal Computing bridges technical systems and human behavior to protect digital infrastructure while respecting user needs. Read more
“VAX: Using Existing Video and Audio-based Activity Recognition Models to Bootstrap Privacy-Sensitive Sensors”
Prasoon Patidar’s forward-thinking VAX system ingeniously resolves the critical tension between effective Human Activity Recognition (HAR) and privacy preservation in smart environments like homes and healthcare settings. By leveraging rich video and audio models to bootstrap privacy-sensitive sensors—such as mmWave radars and motion sensors—VAX achieves 90% accuracy in initial detection and trains sensors to 84% accuracy, outperforming traditional methods while slashing user labeling effort by eight times. This innovative transfer learning approach bridges data richness with privacy, generalizing across contexts without invasive monitoring post-training. Readers will be excited by VAX’s potential to revolutionize ubiquitous sensing with privacy-by-design, offering practical, ethical solutions that enhance trust and enable sophisticated applications—embodying S3D’s commitment to purposeful technology at society’s edge. Read more