Pen Testing Child Safety Features
Nov 2025 - Present
Identifying social media child safety features with the goal of developing pen tests to audit the effectiveness of said advertised tools.
- adversarial testing
- child safety
- social media
Introduction
Hi, I'm Lexie Matsumoto.
I'm a PhD student at New York University advised by Damon McCoy. I am part of the Cybersecurity for Democracy lab, a multi-university center for research-driven policy.
My research interests are social media harms and security, ethical AI, and other topics that bridge technical approaches with legislative and policy initiatives.
About me
Who I Am
I am largely interested in how social media and other online platforms impact society, especially more vulnerable populations such as children and marginalized communities. My goal in pursuing research is to inform policy and legislative efforts that promote safer, more equitable online spaces.
When I am not in the lab, you can find me spending too much money in a stationary store, at a cafe with a good book, or on a walk through the park with my dog Venti.
education
New York University
PhD, Computer Science
Cybersecurity for Democracy Lab
2024 — Present
University of Oklahoma
B.S., Computer Science
Minor in Mathematics
2020 — 2024
Research spotlight
Projects
TikTok Polarization
Aug 2024 — Present
Analyzing content volume, polarization, and platform amplification patterns to understand how TikTok shapes divisive discourse and civic engagement.
- social media
- polarization
- mixed methods
Sparse Model Graphing
Aug 2023 — May 2024
Developed an interactive front-end that visualizes variable graphs produced by a 98% accurate Graph Neural Network classifier for sparse matrix detection.
- visualization
- graph neural networks
Autonomous Driving Vision
Aug 2021 — May 2022
Enhanced object detection pipelines for autonomous vehicles using OpenCV and Hough line detection, integrating outputs with LiDAR to reduce collision risk.
- computer vision
- object detection
- opencv
OU Data Analytics Lab
Jan 2021 — May 2021
Partnered with a PhD researcher to investigate Simpson's paradox in public datasets, surfacing misuse risks and crafting guidelines for responsible analysis.
- statistics
- ethics
Published Works
Below are some of my published research papers and articles. Explore them to learn more about my work and contributions to the field.
More and Scammier Ads: The Perils of YouTube's Ad Privacy Settings
PoPETs 2025
Cat Mai, Bruno Coelho∗, Julia Kieserman∗, Lexie Matsumoto∗, Kyle Spinelli∗, Eric Yang∗, Athanasios Andreou, Rachel Greenstadt, Tobias Lauinger, Damon McCoy
readIssues with the TikTok Research API and its effect on researchers
Cybersecurity for Democracy
Bruno Coelho, Lexie Matsumoto, Dominique Geissler
read
Let's collaborate!
I'm always eager to meet researchers, legislators, and organizers who are exploring similar questions. Reach out below!