Pablo Castells @pcastells
Principal Research Scientist at Amazon castells.github.io Madrid, Spain Joined June 2009-
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Photos from @ChenglongM's presentation of "Temporal Conformity-aware Hawkes Graph Network for Recommendations" at the #TheWebConf2004 last week. Preprint available here marksanderson.org/publications/m… @pcastells @RMITComputing @AdmsCentre
Huge congratulations to @ChenglongM for acceptance of his #TheWebConf2024 paper "Temporal Conformity-aware Hawkes Graph Network for Recommendations" with Yongli Ren @pcastells @RMITComputing @AdmsCentre
On arXiv now is a draft chapter on "Generative Information Retrieval Evaluation", examining both GenIR evaluation and using generative for evaluation. Love to hear from you all of references we missed. Co-authored by @Marwah_k @claclarke @NegarEmpr arxiv.org/abs/2404.08137
Are you into generative AI for document retrieval, grounded answer generation, recommendation, knowledge graphs and other modalities? Our paper submission deadline is coming up: 🗓 April 25th Gen-IR #SIGIR2024 coda.io/@sigir/gen-ir-…
💡Important PSA: are you a seasoned #RecSys veteran who already has their single-column ACM template ready to go? We're aligning formatting with other ACM conferences to use the double-column format! Spread the word so no one has to reformat in panic minutes before the deadline.
'More work, less talk' may be a day-to-day motto, but we actually are looking for talks now! The call for industry talks is out: recsys.acm.org/recsys24/call/…. #RecSys2024 is looking for industry practitioners who tackle challenges and find solutions to real-problems. Share your work!
Huge congratulations to @ChenglongM for acceptance of his #TheWebConf2024 paper "Temporal Conformity-aware Hawkes Graph Network for Recommendations" with Yongli Ren @pcastells @RMITComputing @AdmsCentre
Big congratulations to the winner of the Best Paper Award at #RecSys2023!
Interested to know how we can combine effective confidence modelling with competitive recommendation performance and why that matters? Then join the presentation of our #RecSys2023 work with @HarrieOos in Hall406CX at 14:40 Singapore time! Paper: dl.acm.org/doi/10.1145/36…
Listening to @yashonwu presenting our work at #recsys2023 - the paper is entitled “Goal-Oriented Multi-Modal Interactive Recommendation with Verbal and Non-Verbal Relevance Feedback”; Now in Session 7: Interactive Recommendation 1
.@asash is presenting our work gSASRec: reducing overconfidence in sequential recommendation trained with negative sampling @ACMRecSys #recsys2023
Extended deadline for LERI23 at #recsys2023 Submission due on August 10th, 2023! We welcome papers on all aspects of impressions for #recsys: models including sequence and context-aware, evaluation, OPE, perspectives, industry... Check our CFP recsyspolimi.github.io/leri2023/cfp/ @ACMRecSys
Still two weeks available to submbit to LERI23, the Workshop on Learning and Evaluating Recommendations with Impressions at #recsys2023 Submissions may cover all aspects related to the use of impressions for #recsys Check our CFP here recsyspolimi.github.io/leri2023/cfp/ @ACMRecSys
Happy to be co-organizer of the Workshop on Learning and Evaluating Recommendations with Impressions, that will be held at #RecSys2023 this September. @ACMRecSys @crmpla67 @pcastells @JustinBasilico Paper submission is in early august, check our CFP here recsyspolimi.github.io/leri2023/cfp/
In the LLM-science discussion, I see a common misconception that science is a thing you do and that writing about it is separate and can be automated. I’ve written over 300 scientific papers and can assure you that science writing can’t be separated from science doing. Why? 1/18
"NEST: Simulating Pandemic-like Events for Collaborative Filtering by Modeling User Needs Evolution" by my student Chenglong Ma, along with @pcastells and Yongli Ren, presented at #cikm2022, is now available for download marksanderson.org/publications/m… @rmit_cidda @RMITComputing
Stellar relevance dataset combining classic LTR features with text queries and documents. Classic LTR with GBDT is still alive. From @macavaney @ntonellotto et al. Thanks to @srchvrs for pointing me to the paper and dataset. istella.ai/data/istella22… eprints.gla.ac.uk/268514/
Back home from #recsys2022? Then it's time to think about your next project and keep in mind that #ACM_TORS has currently three special issues with open calls relating to #trust, #CausalInference and #Evaluation of #recsys: dl.acm.org/journal/tors/c… #CfP
What a wonderful week at #recsys2022 this was! Thanks and kudos to the General Chairs, and all the organizing team. Great program, awesome workshops and tutorials. Looking forward to #recsys2023 in Singapore!
Now @JavierSanzCruza is giving an overview of @Infinitech_EU to the #finrec #recsys2022 project - including hearing a snippet by @jsoldatos et al
I'm psyched to be giving a keynote at the @ACMRecSys Workshop for Online Recommender Systems. I'll be talking about ... ... juice. And a bit about real-time recommender systems. Friday, Sep 23rd, 2pm. Come say hi! Details: orsum.inesctec.pt/orsum2022/, @orsum_ws #RecSys2022
Fernando Diaz @841io
6K Followers 1K Following Associate Professor, CMU. Researcher, Google. Evaluation and design of information retrieval and recommendation systems, including their societal impacts.
Sole Pera @DrCh0le
2K Followers 640 Following Associate Professor @wisdelft @tudelft, Misses Rosario, 🧉 Enthusiast, #RecSys #InformationRetrieval #IR4U2 #KidRec
Claudia Hauff 🇪�... @CharlotteHase
4K Followers 2K Following IR * Applied NLP * Applied ML. Spotify.
Glasgow IR Group @ir_glasgow
1K Followers 137 Following Glasgow Information Retrieval Group @GlasgowCS
Hitarth Narvala @hitarth_08
494 Followers 269 Following PhD @ir_glasgow @GlasgowCS, University of Glasgow
Sean MacAvaney @macavaney
2K Followers 584 Following he/him · Senior Lecturer (Assoc. Professor) at @GlasgowCS @TerrierTeam · working at the intersection of IR&NLP · PhD from @Georgetown IRLab
Daniele Malitesta @dmalitesta
710 Followers 966 Following Postdoc @UniLUISS | Prev. Postdoc @UnivParisSaclay, Ph.D. @PolibaOfficial, visited @InfAtEd | Co-organizer @LoGConference | #Graphs #RecSys #Multimodality.
Giovanni Gabbolini @GGabbolini
278 Followers 207 Following Research scientist @AppleMusic 🇬🇧 Recommender systems and music information retrieval.
Olivier Jeunen @olivierjeunen
880 Followers 500 Following Principal Research Scientist at Aampe. ML/RecSys PhD from @UAntwerpen. Prev. @ShareChatapp, @AmazonScience, @SpotifyResearch, @Facebook, @CriteoAILab.
Ludovico Boratto @ludovicoboratto
433 Followers 401 Following Associate professor of Computer Science @univca and researcher on the impact of Web algorithms on people.
Alan Said @alansaid
2K Followers 415 Following Should be writing (more) papers at @uniofgothenburg/@tillampad_it_GU. #recsys, #research, #education, #artificialintelligence.Mark Sanderson @IR_oldie
4K Followers 260 Following I'm a search engine researcher. I tweet about information retrieval (IR) and uni work. I'm at RMIT University, these are my personal opinions.
Siwei Liu @TedSiwei
416 Followers 526 Following Founder & COO @HowOneAI | We deliver production-ready Agentic AI apps that truly work! Founder at https://t.co/HVp7ERgh4m | ExLect. @aberdeenuni
ACM RecSys @ACMRecSys
5K Followers 998 Following The official feed for #RecSys2025: The ACM Conference on Recommender Systems, 22nd–26th September 2025
Damiano Spina 🦋@da... @damiano10
1K Followers 1K Following PhD in Comp Sci., former DECRA, Senior Lecturer, @RMITComputing, @AdmsCentre. CM Camaleão, Capoeira @ACDP_Australia. Percussionist at @Wombatuque.
Guido Zuccon @guidozuc
2K Followers 746 Following Professor at The University of Queensland, leader of @IELabGroup (https://t.co/yLTRjRQAWA), Information Retrieval researcher
Ietwalbex @Ietwalbex49531
20 Followers 997 Following
Feng_Chiao @Chia_Chiao_H
1 Followers 213 Following
Ernesto Cohnen @cohnen
1K Followers 3K Following Let’s change Travel together! ✈️ + 🏨+🚂+🚀 SVP AI Products @ ixigo 🇮🇳 | Co-Founder @ Triporate
Slairs @SlairswxP
92 Followers 2K Following
Paco González-Blanch @fgblanch
947 Followers 5K Following
Georgina Cosma @gcosma1
16K Followers 16K Following Professor of AI @lborouniversity Neural Information Processing, Retrieval & Modelling, NLP, LLM Learning & Unlearning, AI Ethics, AI in Health &Social Care
RSTLess group @RSTLessGroup
151 Followers 193 Following @SapienzaRoma, @DIAGSapienza Research Group PI: Fabrizio Silvestri @fabreetseo
PaulaHoratio @N0crKfVkQ2YY11b
63 Followers 7K Following
Till @matip
300 Followers 419 Following NLProc, Information Retrieval, User Modeling, Personalization, Data Mining, Lifelogging
Shubhankar Sharma @MascotVashishth
283 Followers 4K Following Chief User @ Stealth AI Startup | Applied Machine Learning | ex - ShareChat, Nvidia, Slice, WishLink, Ericsson | IIIT Bhopal 22 | RecSys, Search, LLM
Nicola Cecere @NicolaCecere18
7 Followers 59 Following Applied Scientist @AmazonScience | MSc. @EIT_Digital double degree | GenAI Uncertainty Estimation, Information Retrieval, Recommender Systems, NLP
ACM CIKM 2024 @cikm2024
260 Followers 143 Following 33rd ACM International Conference on Information and Knowledge Management #cikm2024 Follow CIKM'25 at @cikm2025
MuRS Workshop @ RecSy... @MuRS_WS
42 Followers 213 Following The 3rd Workshop on Music Recommender Systems. September at the ACM RecSys 2025 Conference in Prague, Czech Republic (and online) #RecSys2025
totopampin @totopampin
7 Followers 22 Following
Peter Morales @PeterMoralesX
364 Followers 3K Following Founder, CEO of Code Metal. Interested in development at the edge? DM.
Zhi-Quan Feng @ZhiQuanFeng1046
1 Followers 43 Following
Faeze Ghorbanpour @FaezeGhorbanpor
124 Followers 2K Following NLP Researcher and PhD Student at @TU_Muenchen Affiliated with @MunichCenterML
Intelligence & Roboti... @OAE_IR
212 Followers 468 Following Intelligence & Robotics (IR) | Research on intelligent systems, robotics, control & AI. Sharing selected papers, trends & opportunities from the community.
Chenchen Han @ChenchenHa42849
17 Followers 76 Following
ALL-Angelina @Shoughth32050
9 Followers 556 Following Aproveite a oportunidade,junte-se a All,ganhe mais de 200 por dia,se estiver interessado,por favor,tome a iniciativa de conversar comigo em particular!
Stephen Hendry (Sloga... @sloganeerjoseph
26 Followers 403 Following 7 times and youngest ever world snooker champion. Life is not a bed of roses.. Stand up and face it.. Retweet Relevant News
Recommender-Systems.c... @RecSys_c
773 Followers 214 Following Latest recommender-systems news (#recsys). Add #RS_c to your tweet to be featured on http://recommender-systems. For recsys jobs, add #RS_c_Jobs.
Bilal seif Bilal seif @BilalseifB95406
429 Followers 2K Following
Wisdomloju @wisdomloju2025
1 Followers 96 Following
Ayoub Elmajjodi @ayelmajjodi
347 Followers 2K Following PhD Student @UIB Research Group: https://t.co/EfFnjab7Kp @SFIMediaFutures #MediaFutures #RecSys, #Digital_Nudging #FoodRecommendations
Youssef Emam @yyoussefemam
285 Followers 922 Following
Knick Knack @KnickKn84910636
1 Followers 20 Following
bingfeng @bingfeng777107
0 Followers 69 Following
Peter Brusilovsky @peterpaws
2K Followers 241 Following Professor of Information Science and Intelligent Systems at the University of Pittsburgh
El Goloso Campus @elgolosocampus
7 Followers 30 Following Restaurante en el campus de la Universidad Autónoma de Madrid, con desayunos, carta y menús diarios.
Parag Namjoshi @ParagNamjoshi
22 Followers 1K Following
ECIR2024 @ecir2024
623 Followers 120 Following European Conference on Information Retrieval 2024 in Glasgow, Scotland.
pauline clark @paulineclark186
39 Followers 568 Following Hello I am a very ambitious person with a great sense of humor I love others as I love myself everyone is the same on this earth and I am convinced that there a
SIGIR-AP 2025 @ACMSIGIR_AP
401 Followers 283 Following 3rd International ACM SIGIR Conference on Information Retrieval in the Asia Pacific (December 7-10, Xi'an, China)
Khalil (on sabbatical... @micaleel
1K Followers 1K Following
Brigitte Ledoux @BrigitteLedoux3
12 Followers 270 Following franchisse des obstacles pour la conquérir, ce qui garantit le début d'une aventure fougueuse et brûlante.
Gianluca Demartini @eglu81
879 Followers 771 Following Prof in #datascience at @UQ_EAIT working on human-in-the-loop #AI for public good, #bias, #fakenews, #democracy, #transparency
Zhi @Zhi40905465
0 Followers 40 Following
Fernando Diaz @841io
6K Followers 1K Following Associate Professor, CMU. Researcher, Google. Evaluation and design of information retrieval and recommendation systems, including their societal impacts.
Sole Pera @DrCh0le
2K Followers 640 Following Associate Professor @wisdelft @tudelft, Misses Rosario, 🧉 Enthusiast, #RecSys #InformationRetrieval #IR4U2 #KidRec
Claudia Hauff 🇪�... @CharlotteHase
4K Followers 2K Following IR * Applied NLP * Applied ML. Spotify.
Nicola Ferro @frrncl
1K Followers 199 Following Information Retrieval, Digital Libraries, Evaluation - Full Professor in Computer Science at @UniPadova, leading @iiia_unipd #RussiaUkraineConflict #againstwar
Glasgow IR Group @ir_glasgow
1K Followers 137 Following Glasgow Information Retrieval Group @GlasgowCS
Jo Kristian Bergum @jobergum
20K Followers 1K Following CEO https://t.co/qdJ3bIZOOU - The retrieval engine built for agents.
Hitarth Narvala @hitarth_08
494 Followers 269 Following PhD @ir_glasgow @GlasgowCS, University of Glasgow
Yann LeCun @ylecun
1.2M Followers 788 Following Professor at NYU & Executive Chairman at AMI Labs. Ex-Chief AI Scientist at Meta. Researcher in AI, Machine Learning, Robotics, etc. ACM Turing Award Laureate.
Sean MacAvaney @macavaney
2K Followers 584 Following he/him · Senior Lecturer (Assoc. Professor) at @GlasgowCS @TerrierTeam · working at the intersection of IR&NLP · PhD from @Georgetown IRLab
Jimmy Lin @lintool
15K Followers 866 Following I profess CS-ly at @UWaterloo. Previously, I monkeyed code for @Twitter, slides for @Cloudera, and scienced for @yupp_ai.
Giovanni Gabbolini @GGabbolini
278 Followers 207 Following Research scientist @AppleMusic 🇬🇧 Recommender systems and music information retrieval.
Olivier Jeunen @olivierjeunen
880 Followers 500 Following Principal Research Scientist at Aampe. ML/RecSys PhD from @UAntwerpen. Prev. @ShareChatapp, @AmazonScience, @SpotifyResearch, @Facebook, @CriteoAILab.
Ludovico Boratto @ludovicoboratto
433 Followers 401 Following Associate professor of Computer Science @univca and researcher on the impact of Web algorithms on people.
Alan Said @alansaid
2K Followers 415 Following Should be writing (more) papers at @uniofgothenburg/@tillampad_it_GU. #recsys, #research, #education, #artificialintelligence.Mark Sanderson @IR_oldie
4K Followers 260 Following I'm a search engine researcher. I tweet about information retrieval (IR) and uni work. I'm at RMIT University, these are my personal opinions.
Siwei Liu @TedSiwei
416 Followers 526 Following Founder & COO @HowOneAI | We deliver production-ready Agentic AI apps that truly work! Founder at https://t.co/HVp7ERgh4m | ExLect. @aberdeenuni
Antonio Papell @Apapell
78K Followers 2K Following Periodista y escritor español. Ingeniero. Últimos libros: “La Corona y los partidos” (2024) y "Los ingenieros de caminos y el progreso de España" (2025).
José Vico 🔻🇵�... @josevico4
126K Followers 25K Following Llevamos un mundo nuevo en nuestros corazones, y ese mundo está creciendo en este instante. Buenaventura Durruti ❤️ 🖤 ✊
ACM CIKM 2024 @cikm2024
260 Followers 143 Following 33rd ACM International Conference on Information and Knowledge Management #cikm2024 Follow CIKM'25 at @cikm2025
totopampin @totopampin
7 Followers 22 Following
Norman Knyazev @NormanKnyazev
80 Followers 181 Following PhD Candidate at @Radboud_Uni: Statistical Biases, Machine Learning, RecSys | Previously: Research Intern @Snap, Applied Science Intern @AmazonScience.
ECIR2024 @ecir2024
623 Followers 120 Following European Conference on Information Retrieval 2024 in Glasgow, Scotland.
Melbourne Search and ... @MelbourneSearch
117 Followers 113 Following An unofficial, relaxed gathering to allow some fruitful discussions on search and recsys challenges. Currently organised by @damiano10 @IR_oldie @lorryboy
Recommender-Systems.c... @RecSys_c
773 Followers 214 Following Latest recommender-systems news (#recsys). Add #RS_c to your tweet to be featured on http://recommender-systems. For recsys jobs, add #RS_c_Jobs.
eugene @eugeneyalt
1K Followers 134 Following Care a lot, try hard, have fun. @eugeneyan's Id. 🏂 Anonymous feedback: https://t.co/ALNKEgfDuN
@timnitGebru (@dair-c... @timnitGebru
172K Followers 3K Following Personal Account Author: The View from Somewhere Mastodon @[email protected] BlueSky https://t.co/XAYRV7YPvQ Also on LinkedIn. Less here
Gianluca Demartini @eglu81
879 Followers 771 Following Prof in #datascience at @UQ_EAIT working on human-in-the-loop #AI for public good, #bias, #fakenews, #democracy, #transparency
Christopher Manning @chrmanning
164K Followers 323 Following Founder @stanfordnlp & cs224n—Senior Fellow @StanfordHAI—Prof. CS & Linguistics @Stanford—GP @aixventureshq—MTS @moonlake—Australian🇦🇺—Do #NLProc & #AI 👋
Andrew Ng @AndrewYNg
1.6M Followers 1K Following Co-Founder of Coursera; Stanford CS adjunct faculty. Former head of Baidu AI Group/Google Brain. #ai #machinelearning, #deeplearning #MOOCs
Richard Sutton @RichardSSutton
64K Followers 59 Following Student of mind and nature, libertarian, chess player, cancer survivor. @ Keen, UAlberta, Amii, https://t.co/u8za2Kod54, The Royal Society, Turing Award
Mirko Marras @mirkomarras
280 Followers 452 Following Assistant Professor at @univca 🇮🇹 | former Postdoc @EPFL 🇨🇭 Intern @nyuniversity 🇺🇸 @UPLasPalmasGC 🇪🇸 @Eurecat_news 🇪🇸 | #ML #FAccT #IR #AIED #UMAP
Lucio Narducci @LucioNarducci
327 Followers 466 Following Full Professor @ Politecnico di Bari - Recommender Systems, Artificial Intelligence, Conversational Agents
Leo Boytsov @srchvrs
9K Followers 2K Following Machine learning scientist and engineer speaking πtorch & C++. Past @LTIatCMU, @awscloud. Opinions sampled from MY OWN 100T param LM.
Zhaochun Ren @zhaochun_ren
1K Followers 930 Following Associate Professor @TMLeiden, @LIACS, @UniLeiden, working on Information Retrieval and Natural Language Processing. My tweets are my own.
RELISON @RELISON_IR
13 Followers 37 Following A Java framework for REcommending LInks in SOcial Networks.
Ciarán Gilligan-Lee @quantumciaran
3K Followers 994 Following Causal Inference & ML | Head of Causal Inference Research Lab @spotifyresearch & Honorary Associate Professor @ucl | Ex @CompSciOxford & @Perimeter
Mehdi Elahi @mehdielaahi
349 Followers 617 Following Professor in 🇳🇴 Social Science Faculty @UiB WP-Leader @SFIMediaFutures Co-founder of https://t.co/KE0FEhivwO Group Former member of @Polimi @UniBz
ACM Transactions on t... @TWebACM
203 Followers 346 Following ACM Transactions on the Web (TWeb) publishes refereed articles on Web-related research. Accepted articles may be presented at @TheWebConf.
Gabriel Moreira @gspmoreira
1K Followers 1K Following Scientist passionate about solving problems with AI. Researcher @ NVIDIA, Phd. in ML, GDE in ML, Data Scientist, Seventh Day Adventist, Vegetarian, Father
Masoud Mansoury @MansouryMasoud
283 Followers 167 Following Assistant Professor at @tudelft | Previously Postdoc @AmlabUva
Yaxiong Wu @yashonwu
260 Followers 302 Following AI Researcher | Ex @Huawei (Singapore) | PhD @UofGlasgow (Scotland) | Opinions are my own
Ryen White @ryen_white
431 Followers 73 Following @Microsoft VP | @UW Prof (CSE & iSchool) | @TWebACM EiC | @TheOfficialACM Fellow | @BCS Fellow | SIGIR & SIGCHI Academy | @CHIIR 2026 GC | @Mariners 🔱
Negar Arabzadeh @NegarEmpr
1K Followers 1K Following Postdoc @UCBerkeley @BerkeleySky |👩🏻💻Prev @google, @MSFTResearch, @SpotifyResearch | 📚@UWaterloo | Interested in Information Retrieval
Mete Sertkan @m_sertkan
254 Followers 639 Following Research assistant and PhD student @tu_wien; working on user-modeling, recommender systems, and personalization
Pavel Kordík @pavelkordik
1K Followers 483 Following Data scientist interested in data mining automation, meta-learning, artificial intelligence and optimization @FIT_CTU, @DataLab_CTU, @recombee @prg_ai
Vojtěch Vančura @zombadin
98 Followers 437 Following Coding since 1988. RecSys research @recombee @matfyz
Maria Vlachou @mvlacho1
170 Followers 137 Following Postdoctoral Researcher at @uni_copenhagen Language and Multimodal Processing Group. Previously PhD @TerrierTeam & @Social__AI, @UofGlasgow
Arushi Prakash (She/H... @arushiuw
491 Followers 2K Following Applied Scientist @Apple (RecSys, Knowledge graphs, NLP). Building models and communities PhD from @UWChemE
Aleksandr V. Petrov @asash
686 Followers 265 Following Senior Scientist (IR/RecSys/ML) @Tripadvisor | PhD @ University of Glasgow | Ex. Senior Software Engineer @Amazon | The opinions are mine
Sachin Ahuja @elderofkrikkit
18 Followers 324 Following
Eugene Yan @eugeneyan
27K Followers 662 Following MTS @AnthropicAI. Prev: Principal Applied Scientist @Amazon, led ML @ Alibaba, Lazada, Healthtech startup.
ECIR 2023 @ecir2023
513 Followers 331 Following The 45th European Conference on Information Retrieval, From 2nd to 6th of April 2023
Radek Osmulski @radekosmulski
30K Followers 614 Following LLMs and retrieval by day and other genres of AI when I get the chance 🧪 Senior AI Eng @NVIDIAAI 🏫 @fastdotai trained DL Eng 📝 https://t.co/By87iXx5Pu
Yashar Deldjoo @yashardel
860 Followers 2K Following Associate Professor @polibaofficial; #RecSys #GenerativeAI #FairML #TrustworthyAI #Risks #Harm #Evaluation
Felice Antonio Merra @merrafelice
492 Followers 410 Following Ph.D. in ML | Data Science Manager at Cognism | Ex Applied Scientist at Amazon | RecSys & GenAI Enthusiast

























