Rafael Ferreira

Ph.D. Student at Nova School of Science and Technology, Portugal
  rah [dot] ferreira [at] campus [dot] fct [dot] unl [dot] pt

Hello,

My name is Rafael Ferreira, and I am a Ph.D. student at NOVA School of Science and Technology in Portugal.
I finished my M.SC. in Computer Science in 2021 at NOVA with my thesis, where I approached the problem of conversational search using state-of-the-art models in query-rewriting, response re-ranking, and context tracking.

Currently, I am working on the subject of AI-based conversational assistants, specifically designed to help users efficiently complete complex manual tasks. My research aims to improve the robustness and behavior of conversational agents with the aim of developing next-generation systems that exhibit more human-like understanding and characteristics.

I also had the opportunity to be the team lead for the award-winning TWIZ team in both editions of the Alexa Prize TaskBot Challenge.

My interests include Conversational Agents, Natural Language Processing, Machine Learning, and Multimodal AI.

For more information about my work, please visit the links present in this page.

Academic Degrees

Ph.D. Student

Nova School of Science and Technology

Exploring the subject of dialogue policy for conversational task-oriented dialogue agents.
Under the supervision of Prof. João Magalhães and Prof. David Semedo.

2021 - Present

M.Sc. in Computer Science

Nova School of Science and Technology

M.Sc. Thesis: Context Tracking in Conversational Search: from Utterances to Neural Embeddings. [PDF] [Cite]
Under the supervision of Prof. João Magalhães and Prof. David Semedo.

2018 - 2021

B.Sc. in Computer Science

Nova School of Science and Technology

2015 - 2018

Preprints and Publications

For more information about my publications please visit my google scholar profile here.

Multi-trait User Simulation with Adaptive Decoding for Conversational Task Assistants
Rafael Ferreira, David Semedo and João Magalhães.
EMNLP, 2024. [PDF] [Cite]
2024

Plan-Grounded Large Language Models for Dual Goal Conversational Settings
Diogo Silva, Rafael Ferreira, Diogo Tavares, David Semedo and João Magalhães.
EACL, 2024. [PDF] [Cite]
2024

TWIZ-v2: The Wizard of Multimodal Conversational-stimulus
Rafael Ferreira, Diogo Tavares, Diogo Silva, Rodrigo Valério, João Bordalo, Inês Simões, Vasco Ramos, David Semedo and João Magalhães.
Alexa Prize TaskBot Challenge 2 Proceedings, 2023. [PDF] [Cite]
2023

Grounded Complex Task Segmentation for Conversational Assistants
Rafael Ferreira, David Semedo and João Magalhães.
SIGDIAL, 2023. [PDF] [Cite]
2023

The Wizard of Curiosities: Enriching Dialogues with Fun Facts
Frederico Vicente, Rafael Ferreira, David Semedo and João Magalhães.
SIGDIAL, 2023. [PDF] [Cite]
2023

Beyond Browser Online Shopping: Experience Attitude Towards Online 3D Shopping with Conversational Agents
Pedro Valente, Tiago Fornelos, Rafael Ferreira, Diogo Silva, Diogo Tavares, Nuno Correia, João Magalhães and Rui Nóbrega.
INTERACT, 2023. [PDF] [Cite]
2023

Rating Prediction in Conversational Task Assistants with Behavioral and Conversational-Flow Features
Rafael Ferreira, David Semedo and João Magalhães.
SIGIR, 2023. [PDF] [Cite]
2023

TWIZ: A Conversational Task Wizard with Multimodal Curiosity-Exploration
Rafael Ferreira, Diogo Tavares, Diogo Silva, Frederico Vicente, Mariana Bonito, Gustavo Gonçalves, Rui Margarido, Paula Figueiredo, Helder Rodrigues, David Semedo and João Magalhães.
Alexa Prize TaskBot Challenge Proceedings, 2022. [PDF] [Cite]
2022

Open-domain conversational search assistants: the Transformer is all you need
Rafael Ferreira, Mariana Leite, David Semedo and João Magalhães.
Information Retrieval Journal, 2022 [PDF] [Cite]
2022

iFetch: Multimodal Conversational Agents for the Online Fashion Marketplace
Ricardo Gamelas Sousa, Pedro Miguel Ferreira, Pedro Moreira Costa, Pedro Azevedo, João Paulo Costeira, Carlos Santiago, João Magalhães, David Semedo, Rafael Ferreira, Alexander I Rudnicky and Alexander Georg Hauptmann.
ACM Multimedia, MuCAI Workshop, Virtual Event/Chengdu 2021. [PDF] [Cite]
2021

Knowledge-driven Answer Generation for Conversational Search
Mariana Leite, Rafael Ferreira, David Semedo and João Magalhães. [PDF] [Cite]
2021

BERT Embeddings Can Track Context in Conversational Search
Rafael Ferreira, David Semedo and João Magalhães. [PDF] [Cite]
2021

Open-Domain Conversational Search Assistant with Transformers
Rafael Ferreira, Mariana Leite, David Semedo and João Magalhães.
ECIR 2021, Lucca, Italy, March 2021.
Selected as one of the top-8 best papers of the conference. [PDF] [Cite]
2021

Tracking Context in Conversational Search: From Utterances to Neural Embeddings
Rafael Ferreira, João Magalhães and David Semedo. M.Sc.
Thesis in Computer Science. [PDF] [Cite]
2021

NOVA at TREC 2020 Conversational Assistance Track
Rafael Ferreira, David Semedo and João Magalhães.
TREC CAsT 2020, Virtual Event, November 2020. [PDF] [Cite]
2020

Projects and Others

Silicium Sailor (Grumete Silicio)

Project Manager for the development of Silicium Sailor (Grume Silicio), an advanced on-premises Conversational Retrieval-Augmented Generation (RAG) system featuring multimodal question-answering capabilities tailored for Navy and NATO operational protocols. Successfully showcased at the REPMUS 2024 military innovation event.

2024

TWIZ - Alexa Prize TaskBot Challenge 2nd Edition

Team Lead of team TWIZ (Task WIZard) and winner of the 2nd edition of the Alexa Prize TaskBot Challenge. Competition sponsored by Amazon where 10 universities compete to develop agents that assist customers in completing tasks.
Conversational AI challenge that incorporates multimodal (voice and vision) customer experiences.

2022 - 2023

iFetch

Multimodal conversational agents for online marketplaces. iFetch is composed of a multidisciplinary team with strong competence in key areas such as multimedia, computer vision, AI, and language understanding from both universities and Farfetch.

2021 - 2023

TWIZ - Alexa Prize TaskBot Challenge 1st Edition

Team Lead of team TWIZ (Task WIZard) on the 1st edition of the Alexa Prize TaskBot Challenge, which finished in 2nd place. Competition sponsored by Amazon where 10 universities compete to develop agents that assist customers in completing tasks.

2021 - 2022

NOVASearch

Member of the research group NOVASearch at Nova School of Science and Technology focused on information retrieval, natural language processing, and multimodal applications.

2019 - Present

GoLocal

Project (CMUP-ERI/TIC/0046/2014) - From Monitoring Global Data Streams to Context-aware Recommendation where the main research areas are Information and Communications Technologies.

2019-2020

Honours and Awards

Achieved 1st place in the the Alexa Prize TaskBot Challenge 2022
Team Lead of team TWIZ (Task WIZard) on the 2nd edition of the Alexa Prize TaskBot Challenge, finishing in 1st place.
2023

Achieved 2nd place in the the Alexa Prize TaskBot Challenge 2021
Team Lead of team TWIZ (Task WIZard) on the 1st edition of the Alexa Prize TaskBot Challenge, finishing in 2nd place.
2022

Academic Merit Scholarship
Received a scholarship due to academic merit by having one of the top-3 highest average grades for students in the 5th year of the university.
2020