work SigmaLoop A self-improving agent loop that autonomously optimizes coding agents through continuous iteration, failure analysis, and gated evaluation — no model upgrades required. GraphRAG Repair Chatbot An appliance repair assistant powered by a Neo4j knowledge graph and dual-retrieval RAG — graph queries and semantic search working in parallel. quant Copula Pairs Trading Time-varying and mixed copula models for nonlinear pairs trading — selected to represent NYU at the IAQF 2023 competition. Fixed Income Quant Trading Cointegrated butterfly strategies on Eurodollar futures — AR(1) signal forecasting, signal combination, and quality metrics across market regimes. HRL Goal-Based Investing Hierarchical reinforcement learning for goal-based investing — a two-tiered framework that unifies stock selection and portfolio optimization for medium-long horizon investment.