A valuable page in this cluster because his public role description is unusually specific: post-training, steerability, and AI-generated evaluation data are exactly the kinds of practical problems strong researcher pages should make discoverable.
Researcher Profile
Editor reviewedNir Ratner
Hybrid Transformer–Mamba language models (Jamba)
Researcher behind AI21's long-context prompting, factuality evaluation, and hybrid-model work
A useful page for understanding the AI21 thread that connects long-context prompting tricks, factuality benchmarks, and modular language-model systems rather than treating those as separate subfields.
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About This Page
This profile is meant to help you get oriented quickly: why this researcher matters, what to read first, and where to explore next.
Last reviewed
March 18, 2026
Known For
The ideas, systems, and research directions that make this person worth knowing.
01
Parallel Context Windows for long-context prompting
02
Factuality evaluation for language models
03
MRKL and Jamba-era AI21 language-model systems
04
Hybrid Transformer–Mamba language models (Jamba)
05
Jamba: A Hybrid Transformer-Mamba Language Model
06
Jamba-1.5: Hybrid Transformer-Mamba Models at Scale
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