Person

Manoel Horta Ribeiro

Related publications (13)

Post Guidance for Online Communities

Effective content moderation in online communities is often a delicate balance between maintaining content quality and fostering user participation. In this paper, we introduce post guidance, a novel approach to community moderation that proactively guides ...

Association for Computing Machinery (ACM)2025

Deplatforming Norm-Violating Influencers on Social Media Reduces Overall Online Attention Toward Them

Robert West, Manoel Horta Ribeiro

From politicians to podcast hosts, online platforms have systematically banned (''deplatformed'') influential users for breaking platform guidelines. Previous inquiries on the effectiveness of this intervention are inconclusive because 1) they consider onl ...

Association for Computing Machinery (ACM)2025

Community-Driven Models for Research on Social Platforms

Manoel Horta Ribeiro

This SIG will engage CSCW researchers in a collaborative discussion on the use of UGC from social platforms for academic research. In recent years, both the importance and difficulty of accessing such data for scientific inquiry have increased. Drawing on ...

Association for Computing Machinery2024

Content Moderation in Online Platforms

Manoel Horta Ribeiro

A critical role of online platforms like Facebook, Wikipedia, YouTube, Amazon, Doordash, and Tinder is to moderate content. Interventions like banning users or deleting comments are carried out thousands of times daily and can potentially improve our onlin ...

EPFL2024

Causally estimating the effect of YouTube's recommender system using counterfactual bots

Robert West, Manoel Horta Ribeiro

the effects of the algorithm from a user's intentions. Here we propose a method that we call "counterfactual bots" to causally estimate the role of algorithmic recommendations on the consumption of highly partisan content on YouTube. By comparing bots that ...

National Academy of Sciences2024

Understanding Online Migration Decisions Following the Banning of Radical Communities

Manoel Horta Ribeiro

The proliferation of radical online communities and their violent offshoots has sparked great societal concern. However, the current practice of banning such communities from mainstream platforms has unintended consequences: (i) the further radicalization ...

New York2023

Deplatforming did not decrease Parler users' activity on fringe social media

Robert West, Manoel Horta Ribeiro

Online platforms have banned ("deplatformed") influencers, communities, and even entire websites to reduce content deemed harmful. Deplatformed users often migrate to alternative platforms, which raises concerns about the effectiveness of deplatforming. He ...

OXFORD UNIV PRESS2023

Analyzing the "Sleeping Giants" Activism Model in Brazil

Manoel Horta Ribeiro

In 2020, amidst the COVID pandemic and a polarized political climate, the Sleeping Giants online activist movement gained traction in Brazil. Its rationale was simple: to curb the spread of disinformation by harming the advertising revenue of sources that ...

New York2022

Deep neural network-estimated electrocardiographic age as a mortality predictor

Manoel Horta Ribeiro

The electrocardiogram (ECG) is the most commonly used exam for the screening and evaluation of cardiovascular diseases. Here, the authors propose that the age predicted by artificial intelligence from the raw ECG tracing can be a measure of cardiovascular ...

Nature Portfolio2021

Volunteer contributions to Wikipedia increased during COVID-19 mobility restrictions

Robert West, Manoel Horta Ribeiro

Wikipedia, the largest encyclopedia ever created, is a global initiative driven by volunteer contributions. When the COVID-19 pandemic broke out and mobility restrictions ensued across the globe, it was unclear whether contributions to Wikipedia would decr ...

Nature Portfolio2021

Auditing Radicalization Pathways on YouTube

Robert West, Manoel Horta Ribeiro

Non-profits, as well as the media, have hypothesized the existence of a radicalization pipeline on YouTube, claiming that users systematically progress towards more extreme content on the platform. Yet, there is to date no substantial quantitative evidence ...

ASSOC COMPUTING MACHINERY2020

Automatic 12-lead ECG Classification Using a Convolutional Network Ensemble

Manoel Horta Ribeiro

The 12-lead electrocardiogram (ECG) is a major diagnostic test for cardiovascular diseases and enhanced automated analysis tools might lead to more reliable diagnosis and improved clinical practice. Deep neural networks are models composed of stacked trans ...

IEEE2020

Message Distortion in Information Cascades

Robert West, Kristina Gligoric, Manoel Horta Ribeiro

Information diffusion is usually modeled as a process in which immutable pieces of information propagate over a network. In reality, however, messages are not immutable, but may be morphed with every step, potentially entailing large cumulative distortions ...

ASSOC COMPUTING MACHINERY2019