Dr. Omar Khattab
Stanford NLP Postdoctoral Scholar
Verified Proof of Work Artifacts
2 items catalogedEach artifact below represents an authenticated research publication, production code repository, or technical architectural framework directly authored or co-created by Dr. Omar Khattab. Every entry undergoes editorial source verification.
ColBERT: Efficient and Effective Passage Search via Contextualized Late Interaction over BERT
Invented ColBERT, a neural retrieval model utilizing late interaction over token-level representations rather than collapsing documents into a single dense vector, achieving cross-encoder retrieval quality with millisecond vector search latency.
Multi-vector token index storage requires larger RAM and disk allocations than single-vector embedding stores unless aggressive centroid quantization (ColBERTv2 / PLAID) is applied.
DSPy Assertions: Computational Constraints for Self-Refining Language Model Pipelines
Authored the DSPy Assertions paradigm, introducing computational assertions and suggestions directly into declarative LM graphs, enabling pipelines to self-correct upon constraint failure without manual prompt rewriting.
Backtracking loops require hard iteration ceilings to avoid infinite retry loops when models encounter unresolvable logical contradictions.