Postdoc @UCBerkeley @BerkeleySky |๐Ÿ‘ฉ๐Ÿปโ€๐Ÿ’ปPrev @google, @MSFTResearch, @SpotifyResearch | ๐Ÿ“š@UWaterloo | Interested in Information Retrieval

Berkeley, USA
So excited to share that I received the SIGIR Early Career Research Award! ๐Ÿฅน I still remember attending my first SIGIR, watching someone receive this award, and thinking, โ€œThereโ€™s no way that could ever be me.โ€ And now, here I am!๐Ÿ˜ต This truly means so much to me. Thank you to the @ACMSIGIR community for recognizing my contributions. #SIGIR2026 P.S. Get yourself a PhD supervisor who matches your award-celebration energy ๐Ÿ˜„ So cool to celebrate this moment together! @claclarke
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Negar Arabzadeh retweeted
๐Ÿ“ข ๐—”๐—”๐—”๐—œ ๐Ÿฎ๐Ÿฌ๐Ÿฎ๐Ÿณ ๐—ช๐—ผ๐—ฟ๐—ธ๐˜€๐—ต๐—ผ๐—ฝ ๐—–๐—ฎ๐—น๐—น ๐—ณ๐—ผ๐—ฟ ๐—ฃ๐—ฎ๐—ฝ๐—ฒ๐—ฟ๐˜€ ๐—ง๐—ฟ๐˜‚๐˜€๐˜๐˜„๐—ผ๐—ฟ๐˜๐—ต๐˜† ๐—˜๐˜ƒ๐—ผ๐—น๐˜‚๐˜๐—ถ๐—ผ๐—ป ๐—ผ๐—ณ ๐—”๐—œ ๐—”๐—ด๐—ฒ๐—ป๐˜๐˜€: ๐˜ผ๐™ฃ ๐˜ผ๐™œ๐™š๐™ฃ๐™ฉ ๐™Š๐™ฅ๐™š๐™ง๐™–๐™ฉ๐™ž๐™ฃ๐™œ ๐™Ž๐™ฎ๐™จ๐™ฉ๐™š๐™ข ๐™‹๐™š๐™ง๐™จ๐™ฅ๐™š๐™˜๐™ฉ๐™ž๐™ซ๐™š ๐Ÿ“ ๐—ฃ๐—ฎ๐—น๐—ฎ๐—ถ๐˜€ ๐—ฑ๐—ฒ๐˜€ ๐—–๐—ผ๐—ป๐—ด๐—ฟ๐—ฒฬ€๐˜€, ๐— ๐—ผ๐—ป๐˜๐—ฟ๐—ฒฬ๐—ฎ๐—น, ๐—–๐—ฎ๐—ป๐—ฎ๐—ฑ๐—ฎ ๐Ÿ‡จ๐Ÿ‡ฆ ๐Ÿ—“๏ธ ๐—™๐—ฒ๐—ฏ๐—ฟ๐˜‚๐—ฎ๐—ฟ๐˜† ๐Ÿฎ๐Ÿฎโ€“๐Ÿฎ๐Ÿฏ, ๐Ÿฎ๐Ÿฌ๐Ÿฎ๐Ÿณ (one-day workshop, exact day TBA) AI agents now continuously evolve. How do we keep them trustworthy? ๐Ÿ’ก ๐—ช๐—ต๐˜† ๐—ฎ ๐˜€๐˜†๐˜€๐˜๐—ฒ๐—บ๐˜€ ๐—ฝ๐—ฟ๐—ผ๐—ฏ๐—น๐—ฒ๐—บ? Many failures come not from a broken model, but from a bad memory, an over-privileged tool, or an update that cannot be undone. Operating systems ๐Ÿ–ฅ๏ธ solved this long ago. We bring that lens to agents, making their evolution ๐˜๐—ฟ๐—ฎ๐—ฐ๐—ฒ๐—ฎ๐—ฏ๐—น๐—ฒ, ๐—ฏ๐—ผ๐˜‚๐—ป๐—ฑ๐—ฒ๐—ฑ, ๐—ฎ๐—ป๐—ฑ ๐—ฟ๐—ฒ๐˜ƒ๐—ฒ๐—ฟ๐˜€๐—ถ๐—ฏ๐—น๐—ฒ ๐Ÿ›ก๏ธ ๐Ÿ“Œ ๐—ง๐—ผ๐—ฝ๐—ถ๐—ฐ๐˜€ ๐Ÿง  ๐— ๐—ฒ๐—บ๐—ผ๐—ฟ๐˜† (File systems): provenance, isolation, rollback ๐Ÿ› ๏ธ ๐—ง๐—ผ๐—ผ๐—น๐˜€ & ๐—ฆ๐—ธ๐—ถ๐—น๐—น๐˜€ (Permissions): least privilege, sandboxing, revocation ๐Ÿ“ˆ ๐— ๐—ผ๐—ฑ๐—ฒ๐—น๐˜€ & ๐—ฃ๐—ผ๐—น๐—ถ๐—ฐ๐—ถ๐—ฒ๐˜€ (System updates): versioning, no silent alignment drift ๐Ÿค ๐— ๐˜‚๐—น๐˜๐—ถ-๐—”๐—ด๐—ฒ๐—ป๐˜ (Process isolation): stop one failure from spreading ๐Ÿ“Š ๐—˜๐˜ƒ๐—ฎ๐—น๐˜‚๐—ฎ๐˜๐—ถ๐—ผ๐—ป (Logging): trace every failure to the change behind it ๐ŸŽค ๐—ฆ๐—ฝ๐—ฒ๐—ฎ๐—ธ๐—ฒ๐—ฟ๐˜€ & ๐—ฃ๐—ฎ๐—ป๐—ฒ๐—น๐—ถ๐˜€๐˜๐˜€: @Yoshua_Bengio (UdeM, LawZero, Mila), @MengdiWang10 (Princeton), @du_yilun (Harvard), @hugo_larochelle (Mila), @ZheqingZhu (Pokee AI), and @yzhao010 (USC). โฐ ๐—ž๐—ฒ๐˜† ๐——๐—ฎ๐˜๐—ฒ๐˜€ & ๐—ฆ๐˜‚๐—ฏ๐—บ๐—ถ๐˜€๐˜€๐—ถ๐—ผ๐—ป ๐Ÿ“ Submission deadline: Nov 20, 2026 (AoE) ๐Ÿ“ฌ Author notification: Dec 2, 2026 (AoE) - Full papers: 8 pages; Short / position papers: 4 pages - Double-blind review, AAAI format ๐Ÿ”— ๐—ช๐—ผ๐—ฟ๐—ธ๐˜€๐—ต๐—ผ๐—ฝ ๐—ช๐—ฒ๐—ฏ๐˜€๐—ถ๐˜๐—ฒ: trust4rsi-agent.github.io/AAโ€ฆ ๐Ÿ“ ๐—ฃ๐—ฎ๐—ฝ๐—ฒ๐—ฟ ๐—ฆ๐˜‚๐—ฏ๐—บ๐—ถ๐˜€๐˜€๐—ถ๐—ผ๐—ป: openreview.net/group?id=AAAIโ€ฆ ๐Ÿ“ข ๐—œ๐—ป๐˜๐—ฒ๐—ฟ๐—ฒ๐˜€๐˜๐—ฒ๐—ฑ ๐—ถ๐—ป ๐—ฏ๐—ฒ๐—ฐ๐—ผ๐—บ๐—ถ๐—ป๐—ด ๐—ฎ ๐˜„๐—ผ๐—ฟ๐—ธ๐˜€๐—ต๐—ผ๐—ฝ ๐˜€๐—ฝ๐—ผ๐—ป๐˜€๐—ผ๐—ฟ? Contact us at trust4rsi.agent@gmail.com Happy to organize with @NegarEmpr, @HuaWenyue31539, @BangL93, and @lcharlin. Big thanks to the support and advisory from @StevenYuan666, Yankai Chen, Tianyu Shi, @BokwaiHo, @preslav_nakov, Steve Liu, @alex_pentland We look forward to seeing you in Montrรฉal! ๐Ÿ‡จ๐Ÿ‡ฆ #AAAI2027 #AIAgents #TrustworthyAI #AISafety #LLM #CallForPapers
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Excited to be co-organizing our Trust4RSI-Agent Workshop at #AAAI2027 ! A Workshop on Trustworthy Evolution of AI Agents! ๐Ÿš€ ๐ŸฅณWe have an amazing lineup of speakers and panelists: @Yoshua_Bengio , @MengdiWang10 , @du_yilun , @hugo_larochelle , @ZheqingZhu , and @__yuezhao__ ! ๐Ÿ“ Submission deadline: November 20, 2026 ๐Ÿ“ฌ Author notification: December 2, 2026 ๐Ÿ“ February 22โ€“23, 2027 ยท Montrรฉal, Canada ๐ŸŒ trust4rsi-agent.github.io/AAโ€ฆ Please share with colleagues working in this space and looking forward to your submissions! Happy to be organizing this alongside @Haolun_Wu0203 @HuaWenyue31539 @BangL93 @lcharlin! #AAAI2027 #AIAgents
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Had a great time presenting DeepScholar-Bench at #COLM2026 today! Lots of interesting conversations and interactions! ๐Ÿคฉ If youโ€™re building a deep research system, give our benchmark a try! @COLM_conf has been such an engaging and fun conference so far! ๐Ÿ™Œ
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Today at #COLM2026 I will present DeepScholar-Bench and how we can evaluate AI-generated research synthesis! ๐Ÿ“ Imperial Ballroom, Poster #72 ๐Ÿ•š Today, 11 AMโ€“1 PM Come stop by! Would love to chat!
I'll be BARTing over to #COLM2026 this week ๐Ÿš‡๐Ÿ˜„ Around all week and happy to chat about search agents & deep research systems! ๐Ÿ“„ Thu: DeepScholar-Bench arxiv.org/abs/2508.20033 ๐Ÿ“„ Fri: Multi-Agent Transactive Memory @ Lifelong Agents Workshop arxiv.org/abs/2606.19911
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Negar Arabzadeh retweeted
Replying to @COLM_conf
Agent Swarms are scaling to 1000+ agents, and your message board gets congested. Who builds search for them? #COLM2026 ๐Ÿ“Lifelong Agent workshop (Friday)
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I'll be BARTing over to #COLM2026 this week ๐Ÿš‡๐Ÿ˜„ Around all week and happy to chat about search agents & deep research systems! ๐Ÿ“„ Thu: DeepScholar-Bench arxiv.org/abs/2508.20033 ๐Ÿ“„ Fri: Multi-Agent Transactive Memory @ Lifelong Agents Workshop arxiv.org/abs/2606.19911
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Negar Arabzadeh retweeted
For IR folks: @xueguang_ma and I quickly tested Jev as a pointwise/pairwise/setwise/listwise reranker on the classic DL19 and DL20, reranking the top 100 BM25 results. It is pretty good and cheap.
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Negar Arabzadeh retweeted
Quick intro video on ๐Ÿ’ฐHarnessTax๐Ÿ’ฐ is out!! I also shared some thoughts on what it means for our community to be aware of such cost in coding agents at the end!
Claude Code vs Codex vs Pi: which coding agent wins? @melissapan, PhD candidate at UC Berkeleyโ€™s Sky Computing Lab and previous @arena intern, explored the hidden โ€œharness taxโ€: how the system surrounding an AI model affects its cost and performance. She reports three surprising findings. One: harness choice impacts cost more than accuracy. To learn about all three findings, and what they mean for building useful coding agents on realistic budgets, check out the full video here: piped.video/4R8qZGtEnAE
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Negar Arabzadeh retweeted
Could long-context architectures โ€œfind all contradictionsโ€ in a science literature? Not yet! ๐Ÿงต We study a new class of "high-complexityโ€ tasks whose difficulty scales quadratically with corpus size (as opposed to linearly), reversing common LCLM decisions! (block-sparse attention, hybrid modelsโ€ฆ)
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Negar Arabzadeh retweeted
Impressive paper showing how much the first retrieval step matters for deep research agents. It helps to improve GPT-5.5 from 83.1% to 90.5% on BrowseComp-Plus with the same retriever and the same agent loop. It seems that the gain comes from the opening context. The authors propose Question's Gambit which runs once, before the agent starts searching. It splits the question into clues, turns each clue into complementary searches, pools the results, and reranks them. The agent then starts its loop with that ranked set already in context. The same change lifts GPT-5.4-mini from 68.1% to 79.0% and DeepSeek-v4-pro from 71.4% to 76.9%, and roughly halves calibration error for GPT-5.5. It costs between 2.3 and 5.3 extra tool calls per question. In an error analysis, only 3 of the 79 remaining GPT-5.5 errors come from the gold document never being retrieved. The other 76 happen later, when the agent previews, opens or uses the evidence. Paper: arxiv.org/abs/2609.14412 Chat with Paper: academy.dair.ai/papers/questโ€ฆ
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Thanks @omarsar0 for sharing our paper before we even got the chance to! ๐Ÿ™ Loved your framing so much we borrowed it for our thread "same retriever, same agent loop, just a better opening move. โ™› "
Impressive paper showing how much the first retrieval step matters for deep research agents. It helps to improve GPT-5.5 from 83.1% to 90.5% on BrowseComp-Plus with the same retriever and the same agent loop. It seems that the gain comes from the opening context. The authors propose Question's Gambit which runs once, before the agent starts searching. It splits the question into clues, turns each clue into complementary searches, pools the results, and reranks them. The agent then starts its loop with that ranked set already in context. The same change lifts GPT-5.4-mini from 68.1% to 79.0% and DeepSeek-v4-pro from 71.4% to 76.9%, and roughly halves calibration error for GPT-5.5. It costs between 2.3 and 5.3 extra tool calls per question. In an error analysis, only 3 of the 79 remaining GPT-5.5 errors come from the gold document never being retrieved. The other 76 happen later, when the agent previews, opens or uses the evidence. Paper: arxiv.org/abs/2609.14412 Chat with Paper: academy.dair.ai/papers/questโ€ฆ
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1/ Weโ€™re excited to share Questionโ€™s Gambit module for search agents. โ™› ๐Ÿฅ‡Question Gambit got first on the BrowseComp-Plus leaderboard for recall with BM25 as our only retriever! ๐Ÿ“ˆ It focuses on the first retrieval move in search agents and got 96.6% recall with about 6 times fewer agent search calls. Same BM25 index. Same agent loop. Just a better opening move. ๐Ÿ“„ Paper: arxiv.org/abs/2609.14412
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3/ High recall isnโ€™t enough. The agent has to use what it finds. With GPT-5.5, Pi-Serini surfaces 94.4% of gold documents, but opens or cites only 56.1%. Questionโ€™s Gambit raises these to 98.1% and 75.9%. A much larger gain in evidence use than in retrieval.
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4/ Finally, we're proud that Question's Gambit is the top academic submission on BrowseComp-Plus, at 90.5% answer accuracy. And we're honored to share the top of the leaderboard with @allen_ai @ai2_allennlp , @sailresearchco , and @mixedbreadai . ๐Ÿ™Œ And of course, thanks to the whole BrowseComp-Plus team for maintaining such an interesting benchmark! ๐Ÿ™@xueguang_ma @zijian42chen @luyu_gao @haora @ShengyaoZhuang @crystina_z @beirmug @lintool @WenhuChen ๐Ÿ“œ: arxiv.org/pdf/2609.14412 ๐Ÿ’ป : github.com/radinhamidi/Questโ€ฆ From amazing team: @radin_hrad @amin_bigdelii @sadjadeb @claclarke @ebrahim_bagheri @bfung123
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Negar Arabzadeh retweeted
jev for semantic operators is a great example of how LLM data processing at scale requires rethinking across the stack, model architecture and learning algs included new work and many more thoughts on this coming soon ๐Ÿ‘€ in the meantime, check out lotus, star and stay tuned (link below)
Replying to @ericmao
I borrowed a ton of concepts from the lotus paper. The idea was well ahead of its time. Credit to the core contributors: @lianapatel_ @sid_jha1 @pgasawa @melissapan Harshit Gupta
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Negar Arabzadeh retweeted
Two papers you should read from the information retrieval community about scaling up agent swarms:
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Negar Arabzadeh retweeted
We pretrained a 2.3B MoE (360M active) Hybrid Mamba-2 that lands within a few points of Llama-3.2-3B using <1% of its pretraining FLOPs. No dedicated cluster. The run hopped between H100s, A100s, V100s (yes, V100s) and TPU v5p/v6e on a single codebase. Meet Rigel ๐Ÿงต
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Negar Arabzadeh retweeted
Cool blogpost from Melissa and team on how much the harness matters for coding agents. On the two benchmarks tested, switching harnesses often changed costs much more than success rates, and the default harness of model providers do not necessarily give results that are pareto optimal!
Does your Claude model really need Claude Codeโ€ฆ? ๐Ÿค” We evaluate 7 models on Claude Code, Codex, and Pi. Three surprising findings emerge: 1๏ธโƒฃHarness choice has little effect on task success rate, but can significantly affect the cost 2๏ธโƒฃA simple harness can be competitive 3๏ธโƒฃThe native harness isnโ€™t always the best. Millions of people are using coding agents, but the impact of harness choice remains unclear. (1/n) More details in the thread. ๐Ÿงต
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So we found out that your Claude model might not neccesarily need Claude Code ๐Ÿ‘€
Replying to @melissapan
Finding 1: Harness affects cost more than correctness. Fable 5 can cost twice as much for a 1.1-point gain in success rate. On SWE-bench Lite: - Claude Code: 97.8% accuracy, $1.33/rollout - Pi: 96.7% accuracy, $0.67/rollout While Claude Code reaches the highest success rate on the SWE-bench Lite frontier, Pi and Codex often achieve similar success rates at lower cost across the models we test. So you may be paying a hidden โ€œharness taxโ€ if you pick your harness based only on the success rateโ€ฆ ๐Ÿ’ธ (2/n)
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