Publications

Our teams aspire to make discoveries that impact everyone, and core to our approach is sharing our research and tools to fuel progress in the field.

people standing in front of a screen with images and a chipboard

Our teams aspire to make discoveries that impact everyone, and core to our approach is sharing our research and tools to fuel progress in the field.

Sort By
  • Title
  • Title, descending
  • Year
  • Year, descending
1 - 15 of 10133 publications
    Preview abstract Verifying credentials, such as educational degrees, professional licenses, and permits, is a crucial yet challenging task for organizations globally. Traditional verification methods often rely on third-party vendors, introducing vulnerabilities like bias, security breaches, and privacy risks. While blockchain technology offers a promising solution for credential management, existing approaches often store sensitive credential data off-chain in centralized databases or InterPlanetary File System (IPFS), leaving them susceptible to data breaches and loss. This paper presents a novel, privacy-preserving credential verification system built on a permissioned blockchain network. This system, implemented using the Hyperledger Fabric framework, offers several key advantages over traditional methods, including enhanced security and improved privacy. By leveraging cryptographic techniques, the system ensures the robust and privacypreserving storage of credentials directly on the blockchain. This eliminates the reliance on vulnerable off-chain storage and mitigates associated risks. Furthermore, our analysis of a common credential dataset demonstrates the practical feasibility and cost-effectiveness of our solution, suggesting its widespread adoption. By addressing the limitations of both traditional and existing blockchain-based approaches, our system provides a robust, secure, and efficient solution for credential management in diverse sectors. View details
    SAC124 - SSAC Advice on Name Collision Analysis
    Internet Corporation for Assigned Names and Numbers (ICANN), ICANN Security and Stability Advisory Committee (SSAC) Reports and Advisories (2024), pp. 15
    Preview abstract In this document the Security and Stability Advisory Committee (SSAC) provides its analysis of the findings and recommendations presented within the Name Collision Analysis Project (NCAP) Study Two and the proposed Name Collision Risk Assessment Framework. The SSAC also provides additional commentary on several aspects of the NCAP Study Two Report and makes recommendations to the ICANN Board. View details
    Preview abstract In the present computerized period, information driven navigation is essential for the progress of cooperative work areas. This paper gives an extensive examination of how information designing, distributed storage, and business insight synergistically engage groups. We look at the basic standards of information designing, zeroing in on the plan, development, and the management of adaptable information pipelines. The job of distributed storage is investigated, featuring its ability to give adaptable, secure, and open information arrangements. Besides, we dive into business knowledge instruments and their capacity to change crude information into significant experiences. Through contextual analyses and exact information, we delineate the groundbreaking effect of these advances in group efficiency, coordinated effort, and dynamic cycles. This examination highlights the significance of incorporating hearty information designing works on, utilizing distributed storage arrangements, and utilizing complex business knowledge apparatuses to establish information engaged cooperative conditions. View details
    Preview abstract Interruptions in digital services are a common occurrence for users. These disruptions, however, exact a cost in terms of attention, task completion rate, and, most importantly, emotional state. While several methods currently employed by service providers attempt to address this, the paper will argue that browser games or similar interactive interfaces should become a standard mechanism to ease the aforementioned effects. View details
    Cross-Modality and Equity-Aware Graph Pooling Fusion: A Bike Mobility Prediction Study
    Xi Yang
    Suining He
    Kang G. Shin
    Mahan Tabatabaie
    IEEE Transactions on Big Data (2024)
    Preview abstract We propose an equity-aware GRAph-fusion differentiable Pooling neural network to accurately predict the spatio-temporal urban mobility (e.g., station-level bike usage in terms of departures and arrivals) with Equity (GRAPE). GRAPE consists of two independent hierarchical graph neural networks for two mobility systems — one as a target graph (i.e., a bike sharing system) and the other as an auxiliary graph (e.g., a taxi system). We have designed a convolutional fusion mechanism to jointly fuse the target and auxiliary graph embeddings and extract the shared spatial and temporal mobility patterns within the embeddings to enhance prediction accuracy. To further improve the equity of bike sharing systems for diverse communities, we focus on the bike resource allocation and model prediction performance, and propose to regularize the predicted bike resource as well as the accuracy across advantaged and disadvantaged communities, and thus mitigate the potential unfairness in the predicted bike sharing usage. Our evaluation of over 23 million bike rides and 100 million taxi trips in New York City and Chicago has demonstrated GRAPE to outperform all of the baseline approaches in terms of prediction accuracy (by 15.80% for NYC and 50.55% for Chicago on average) and social equity awareness (by 32.44% and 24.43% in terms of resource fairness for NYC and Chicago, and 13.36% and 16.52% in terms of performance fairness). View details
    Preview abstract Large Language Models have been able to replicate their success from text generation to coding tasks. While a lot of work has made it clear that they have remarkable performance on tasks such as code completion and editing, it is still unclear as to why. We help bridge this gap by exploring to what degree do auto-regressive models understand the logical constructs of the underlying programs. We propose CAPP, a counterfactual testing framework to evaluate whether large code models understand programming concepts. With only black-box access to the model, we use CAPP to evaluate 10 popular large code models for 5 different programming concepts. Our findings suggest that current models lack understanding of concepts such as data flow and control flow. View details
    USM-SCD: USM-Based Multilingual Speaker Change Detection
    Yongqiang Wang
    Jason Pelecanos
    Yu Zhang
    Yiling Huang
    Han Lu
    ICASSP 2024 - 2024 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), pp. 11801-11805
    Preview abstract We introduce a multilingual speaker change detection model (USM- SCD) that can simultaneously detect speaker turns and perform ASR for 96 languages. This model is adapted from a speech foundation model trained on a large quantity of supervised and unsupervised data, demonstrating the utility of fine-tuning from a large generic foundation model for a downstream task. We analyze the performance of this multilingual speaker change detection model through a series of ablation studies. We show that the USM-SCD model can achieve more than 75% average speaker change detection F1 score across a test set that consists of data from 96 languages. On American English, the USM-SCD model can achieve an 85.8% speaker change detection F1 score across various public and internal test sets, beating the previous monolingual baseline model by 21% relative. We also show that we only need to fine-tune one-quarter of the trainable model parameters to achieve the best model performance. The USM-SCD model exhibits state-of-the-art ASR quality compared with a strong public ASR baseline, making it suitable to handle both tasks with negligible additional computational cost. View details
    With Great Power Comes Great Responsibility: Security and Privacy Issues of Modern Browser APIs
    Harun Oz
    Daniele Cono D’Elia
    Abbas Acar
    Riccardo Lazzeretti
    Selcuk Uluagac
    IEEE Security and Privacy (2024)
    Preview abstract This paper discusses security and privacy issues in modern Browser APIs by categorizing them based on their functionality. With this study, we aim to alert the community about these issues and motivate further research into analyzing the security and privacy concerns within modern Browser APIs. View details
    Preview abstract Graphs are a powerful tool for representing and analyzing complex relationships in real-world applications such as social networks, recommender systems, and computational finance. Reasoning on graphs is essential for drawing inferences about the relationships between entities in a complex system, and to identify hidden patterns and trends. Despite the remarkable progress in automated reasoning with natural text, reasoning on graphs with large language models (LLMs) remains an understudied problem. In this work, we perform the first comprehensive study of encoding graph-structured data as text for consumption by LLMs. We show that LLM performance on graph reasoning tasks varies on three fundamental levels: (1) the graph encoding method, (2) the nature of the graph task itself, and (3) interestingly, the very structure of the graph considered. These novel results provide valuable insight on strategies for encoding graphs as text. Using these insights we illustrate how the correct choice of encoders can boost performance on graph reasoning tasks inside LLMs by 4.8% to 61.8%, depending on the task. View details
    Preview abstract A vast amount of human discussion, storytelling, content creation, and reporting now occurs on social media platforms. As such, social media posts are often quoted on web pages as context. In this paper, we argue that these quotations and their surrounding page context provide a rich, platform-independent source of data for studying the intersection of natural language and social media. We introduce a taxonomy of quotation roles that categorizes how social media posts are used within content. We release a dataset of 38M social quotes derived from the Common Crawl, and role labels for a subset assessed by human raters. We show that the interplay of accounts, roles, and topics across the web graph reveal valuable social diffusion patterns, and that roles can be predicted with fine-tuned large language models from web context. View details
    Preview abstract Google Cloud SQL customers encounter PostgreSQL bugs corrupting databases, rarely but reproducibly. This talk will cover use of tools, especially amcheck, to grasp these bugs sufficiently to write fixes and test cases. Those fixes are now part of core PostgreSQL. It will include lessons for avoiding such bugs in future PostgreSQL development. Finally, it will share a diagnostic feature wish list. View details
    Complex Dynamics in Autobidding Systems
    Georgios Piliouras
    Kelly Spendlove
    Proceedings of the 25th ACM Conference on Economics and Computation (2024)
    Preview abstract It has become the default in markets such as ad auctions for participants to bid in an auction through automated bidding agents (autobidders) which adjust bids over time to satisfy return-over-spend constraints. Despite the prominence of such systems for the internet economy, their resulting dynamical behavior is still not well understood. Although one might hope that such relatively simple systems would typically converge to the equilibria of their underlying auctions, we provide a plethora of results that show the emergence of complex behavior, such as bi-stability, periodic orbits and quasi periodicity. We empirically observe how the market structure (expressed as motifs) qualitatively affects the behavior of the dynamics. We complement it with theoretical results showing that autobidding systems can simulate both linear dynamical systems as well logical boolean gates. View details
    Solidarity not Charity! Empowering Local Communities for Disaster Relief during COVID-19 through Grassroots Support
    Jeongwon Jo
    Oluwafunke Alliyu
    John M. Carroll
    Computer Supported Cooperative Work (2024) (2024)
    Preview abstract The COVID-19 pandemic brought wide-ranging, unanticipated societal changes as communities rushed to slow the spread of the novel coronavirus. In response, mutual aid groups bloomed online across the United States to fill in the gaps in social services and help local communities cope with infrastructural breakdowns. Unlike many previous disasters, the long-haul nature of COVID-19 necessitates sustained disaster relief efforts. In this paper, we conducted an interview study with online mutual aid group administrators to understand how groups facilitated disaster relief, and how disaster relief initiatives developed and maintained over the course of the first year of COVID-19. Our findings suggest that the groups were crucial sources of community-based support for immediate needs, innovated long-term solutions for chronic community issues and grew into a vehicle for justice-centered work. Our insights shed light on the strength of mutual aid as a community capacity that can support communities to collectively be more prepared for future long-haul disasters than they were with COVID-19. View details
    SoothSayer: Bypassing DSAC Mitigation by Predicting Counter Replacement
    Salman Qazi
    Fourth Workshop on DRAM Security (DRAMSec) (2024)
    Preview abstract In-DRAM Stochastic and Approximate Counting (DSAC) is a recently published algorithm that aims to mitigate Rowhammer at low cost. Existing in-DRAM counter-based schemes keep track of row activations and issue Targeted Row Refresh (TRR) upon detecting a concerning pattern. However, due to insufficiency of the tracking ability they are vulnerable to attacks utilizing decoy rows. DSAC claims to improve upon existing TRR mitigation by filtering out decoy-row accesses, so they cannot saturate the limited number of counters available for detecting Rowhammer, promising a reliable mitigation without the area cost of deterministic and provable schemes such as per-row activation counting (PRAC). In this paper, we analyze DSAC and discover some gaps that make it vulnerable to Rowhammer and Rowpress attacks. The main focus of this work is a novel attack named SoothSayer that targets the counter replacement policy in DSAC by cloning the random number generator. We describe and simulate this attack, and establish its efficacy. Finally, we discuss other weaknesses in DSAC. View details
    Preview abstract As AI systems quickly improve in both breadth and depth of performance, they lend themselves to creating increasingly powerful and realistic agents, including the possibility of agents modeled on specific people. We anticipate that within our lifetimes it may become common practice for people to create a custom AI agent to interact with loved ones and/or the broader world after death. We call these generative ghosts, since such agents will be capable of generating novel content rather than merely parroting content produced by their creator while living. In this paper, we first discuss the design space of potential implementations of generative ghosts. We then discuss the practical and ethical implications of generative ghosts, including potential positive and negative impacts on individuals and society. Based on these considerations, we lay out a research agenda for the AI and HCI research communities to empower people to create and interact with AI afterlives in a safe and beneficial manner. View details