Publications

2026

  1. Agentic Search in the Wild: Intents and Trajectory Dynamics from 14M+ Real Search Requests
    Ning*, Jingjie, Coelho*, João, Kong*, Yibo, Long, Yunfan, Martins, Bruno, Magalhães, João, Callan, Jamie, and Xiong, Chenyan
    Proceedings of the International ACM SIGIR Conference on Research and Development in Information Retrieval 2026
    arXiv HTML
  2. DeepResearchGym: A Free, Transparent, and Reproducible Sandbox for Deep Research
    Coelho, João, Ning, Jingjie, He, Jingyuan, Mao, Kangrui, Paladugu, Abhijay Sai, Setlur, Pranav, Jin, Jiahe, Callan, Jamie, Magalhães, João, Martins, Bruno, and Xiong, Chenyan
    Proceedings of the ACM SIGIR Conference on Innovative Concepts and Theories in Information Retrieval 2026
    arXiv
  3. Effective Reinforcement Learning for Agentic Search by Recycling Zero-Variance Queries During Training
    Coelho, João, Magalhães, João, Martins, Bruno, and Xiong, Chenyan
    arXiv preprint (under review) 2026
    arXiv
  4. Beyond Parallel Sampling: Diverse Query Initialization for Agentic Search
    Murali, Sidhaarth, Coelho, João, Ning, Jingjie, Magalhães, João, Martins, Bruno, and Xiong, Chenyan
    arXiv preprint (under review) 2026
    arXiv

2025

  1. Aligning Web Query Generation with Ranking Objectives via Direct Preference Optimization
    Coelho, João, Martins, Bruno, Magalhães, João, and Xiong, Chenyan
    Proceedings of the International ACM SIGIR Conference on Research and Development in Information Retrieval 2025
    arXiv HTML

2024

  1. Dwell in the Beginning: How Language Models Embed Long Documents for Dense Retrieval
    Coelho, João, Martins, Bruno, Magalhães, João, Callan, Jamie, and Xiong, Chenyan
    Proceedings of the Annual Meeting of the Association for Computational Linguistics 2024
    HTML

2023

  1. Semantic Similarity for Mobile Application Recommendation under Scarce User Data
    Coelho, João, Paula, Beatriz, Mano, Diogo, Coutinho, Carlos, Oliveira, João, Ribeiro, Ricardo, and Batista, Fernando
    Engineering Applications of Artificial Intelligence 2023
    HTML

2022

  1. Collaborative filtering for mobile application recommendation with implicit feedback
    Paula, Beatriz, Coelho, João, Mano, Diogo, Coutinho, Carlos, Oliveira, João, Ribeiro, Ricardo, and Batista, Fernando
    Proceedings of the IEEE ICE/ITMC Conference 2022

2021

  1. Semantic Search of Mobile Applications using Word Embeddings
    Coelho, João, Neto, António, Tavares, Miguel, Coutinho, Carlos, Oliveira, João, Ribeiro, Ricardo, and Batista, Fernando
    Proceedings of the Symposium on Languages, Applications and Technologies 2021
  2. Transformer-based Language Models for Semantic Search and Mobile Applications Retrieval
    Coelho, João, Neto, António, Tavares, Miguel, Coutinho, Carlos, Oliveira, João, Ribeiro, Ricardo, and Batista, Fernando
    Proceedings of the International Joint Conference on Knowledge Discovery and Information Retrieval 2021
  3. Improving Neural Models for the Retrieval of Relevant Passages to Geographical Queries
    Coelho, João, Magalhães, João, and Martins, Bruno
    Proceedings of the ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems 2021
    HTML