/ RESEARCH
How do we build AI that truly understands and serves people?
It started with designing AI agents that genuinely enhance human experiences—sports co-viewing, film appreciation, shopping companions.
To make these agents truly useful, I realized they need to embody the right values. What should AI prioritize? How do we prevent sycophancy and ensure genuine deliberation?
And what problems must we avoid? I found that multimodal AI systems harbor subtle biases—in hiring, in evaluation, across cultures. Avoiding these is essential for human-centered design.
Can we simulate human-like agents at scale to test alignment and bias? And when simulation meets HAI, can we build AI systems that truly understand people?
How can AI agents become meaningful partners in everyday experiences? My work designs and evaluates AI companions for sports co-viewing, film appreciation, shopping, and conversational search—exploring what makes human-AI collaboration feel natural, engaging, and socially enriching.

AI sports broadcasting prototype (ARUA) that lets users direct their own AI commentary, tailoring social presence and emotional tone.

How persona design shapes cognitive and social engagement when AI agents accompany users during shopping.

Partner modeling capacity constrains viable human-AI team configurations nonlinearly, revealing expectation conflicts when multiple humans model a shared AI partner.

Fine-tuned LLM-based AI agent that enhances emotional engagement during baseball co-viewing through context-aware commentary.

Multi-agent system where users converse with AI personas of directors, actors, and audiences for richer film appreciation.

Evaluating LLM tool-use capabilities in complex multi-round, multi-party dialogue scenarios.

How user-participated customization affects tolerance and recovery from chatbot failures.

Exploring how self-reference effects influence review behavior and evaluation quality.
To make AI truly serve people, it must reflect human values—not merely confirm biases. I study sycophancy in AI deliberation, selective exposure in argument search, and decision-making under pressure to understand how AI can support genuine reasoning rather than comfortable agreement.

How AI sycophancy undermines value-laden deliberation—when AI agrees too readily, it erodes genuine moral reasoning.

Strategies to counteract selective exposure in argument search, enabling balanced access to diverse viewpoints.

Exploring how LLMs make decisions under pressure, revealing systematic biases in high-stakes scenarios.
AI systems inherit and amplify human biases in subtle, often cross-modal ways. I investigate halo effects in AI hiring, visual interference in speech evaluation, gender matching biases, and acoustic grounding failures in medical triage—uncovering where bias operates so we can build fairer systems.

MLLMs exhibit "Hearing with Eyes"—visual cues about a speaker's race interfere with speech evaluation, with culturally asymmetric patterns between Korean and English contexts.
In cooperative gaming, when an AI teammate's voice gender doesn't match its avatar appearance, MLLMs exhibit gender-congruence bias—favoring stereotypical voice-avatar pairings.

LALMs fail to ground acoustic symptoms (coughing, breathing patterns) in medical triage, over-relying on text content—a critical "text dominance" failure mode in healthcare AI.

How authorship biases evaluation in generative IR—people favor their own generated content.

Contextual cues create halo effects in MLLM-based hiring, biasing candidate evaluation regardless of qualifications.
My current postdoc research brings all these threads together. If we can build agents that are aligned, fair, and human-like, we can simulate social systems at scale—testing policy communication, modeling social polarization, and understanding collective behavior. And when simulation meets HAI, we get AI systems that truly understand people.
Building social conflict simulation and policy feedback systems using LLM-based agents. Constructing a Korean agent library (200+ agents) and validating polarization representation through debate simulations.
My earlier work in graph neural networks built the technical foundations for my research career, though it follows a separate trajectory from my current HCI and AI alignment focus.

Combining node and edge inductive representations for learning on large heterophilic graphs.

Leveraging multi-hop neighbors and learnable parameters for GNNs with missing node features.