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Daniel Gatica-Perez

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Related publications (110)

Page 2 of 6

A Thousand Words in a Scene

Daniel Gatica-Perez, Jean-Marc Odobez, Pedro Manuel Da Silva Quelhas

This paper presents a novel approach for visual scene modeling and classification, investigating the combined use of text modeling methods and local invariant features. Our work attempts to elucidate (1) whether a text-like \emph{bag-of-visterms} represent ...

2007

Audio-visual probabilistic tracking of multiple speakers in meetings

Daniel Gatica-Perez, Jean-Marc Odobez, Guillaume Lathoud

Tracking speakers in multiparty conversations constitutes a fundamental task for automatic meeting analysis. In this paper, we present a probabilistic approach to jointly track the location and speaking activity of multiple speakers in a multisensor meetin ...

2006

GAP: Differentially Private Graph Neural Networks with Aggregation Perturbation

Daniel Gatica-Perez, Sina Sajadmanesh

In this paper, we study the problem of learning Graph Neural Networks (GNNs) with Differential Privacy (DP). We propose a novel differentially private GNN based on Aggregation Perturbation (GAP), which adds stochastic noise to the GNN's aggregation functio ...

Usenix Assoc2023

Inferring competitive role patterns in reality TV show through nonverbal analysis

Daniel Gatica-Perez

This paper introduces a new facet of social media, namely that depicting social interaction. More concretely, we address this problem from the perspective of nonverbal behavior-based analysis of competitive meetings. For our study, we made use of "The Appr ...

2012

Privacy-sensitive recognition of group conversational context with sociometers

Daniel Gatica-Perez, Dinesh Babu Jayagopi

Recognizing the conversational context in which group interactions unfold has applications in machines that support collaborative work and perform automatic social inference using contextual knowledge. This paper addresses the task of discriminating one co ...

2011

Examining European Press Coverage of the Covid-19 No-Vax Movement: An NLP Framework

Daniel Gatica-Perez

This paper examines how the European press dealt with the no-vax reactions against the Covid-19 vaccine and the dis- and misinformation associated with this movement. Using a curated dataset of 1786 articles from 19 European newspapers on the anti-vaccine ...

ASSOC COMPUTING MACHINERY2023

Estimating Cohesion in Small Groups Using Audio-Visual Nonverbal Behavior

Daniel Gatica-Perez

Cohesiveness in teams is an essential part of ensuring the smooth running of task-oriented groups. Research in social psychology and management has shown that good cohesion in groups can be correlated with team effectiveness or productivity, so automatical ...

2010

Let Your Body Speak: Communicative Cue Extraction on Natural Interaction Using RGBD Data

Daniel Gatica-Perez

Employment interviews are relevant scenarios for the study of social interaction. In this setting, social skills play an important role, even though the interactions between potential employers and candidates are often limited. One fundamental aspect of so ...

Ieee-Inst Electrical Electronics Engineers Inc2015

Vlogging Over Time: Longitudinal Impressions and Behavior in YouTube

Daniel Gatica-Perez, Dinesh Babu Jayagopi

YouTube vlogging, as a popular genre of ubiquitous social video, engages people in entertainment, civic, and social activities. Although several aspects of vlogging have been studied in media studies and multimedia analysis, the longitudinal angle of vlogg ...

ASSOC COMPUTING MACHINERY2018

The impact of personality in using technology to ask and offer help: the experience of the Chatbot "UC - Paraguay"

Daniel Gatica-Perez

In the context of the project "WeNet: Internet of us" we are studying the role of diversity in relation to Internet-mediated social interactions. In this paper, in particular, we analyze a possible relationship between personality aspects and social intera ...

IEEE2021

Understanding Heavy Drinking at Night through Smartphone Sensing and Active Human Engagement

Daniel Gatica-Perez, Skanda Muralidhar, Thanh Trung Phan

Heavy alcohol consumption can lead to many severe consequences. In this paper, we study the phenomenon of heavy drinking at night (4+ drinks for women or 5+ for men on a single evening), using a smartphone sensing dataset depicting about nightlife and drin ...

ACM2020

Mining Large-Scale Smartphone Data for Personality Studies

Daniel Gatica-Perez

In this paper, we investigate the relationship between automatically extracted behavioral characteristics derived from rich smartphone data and self-reported Big-Five personality traits (Extraversion, Agreeableness, Conscientiousness, Emotional Stability a ...

2013

Referencing in YouTube Knowledge Communication Videos

Daniel Gatica-Perez

In recent years, there has been widespread concern about misinformation and hateful content on social media that are damaging societies. Being one of the most influential social media that practically serves as a newsearch engine, YouTube has accepted crit ...

Assoc Computing Machinery2023

Learning Urban Nightlife Routines from Mobile Data

Daniel Gatica-Perez, Thanh Trung Phan

The use of smartphone sensing for public health studies is appealing to understand routines. We present an approach to learn nightlife routines in a smartphone sensing dataset volunteered by 184 young people (1586 weekend nights with location data captured ...

ACM2020

The YouTube Lens: Crowdsourced Personality Impressions and Audiovisual Analysis of Vlogs

Daniel Gatica-Perez, Joan Isaac Biel Tres

Despite an increasing interest in understanding human perception in social media through the automatic analysis of users' personality, existing attempts have explored user profiles and text blog data only. We approach the study of personality impressions i ...

Ieee-Inst Electrical Electronics Engineers Inc2013

Assessing Sparse Coding Methods for Contextual Shape Indexing of Maya Hieroglyphs

Daniel Gatica-Perez, Jean-Marc Odobez, Edgar Roman Rangel

Bag-of-visual-words or bag-of-visterms (bov) is a common technique used to index Multimedia information with the purposes of retrieval and classification. In this work we address the problem of constructing efficient bov representations of complex shapes a ...

2012

The Theory, Practice, and Ethical Challenges of Designing a Diversity-Aware Platform for Social Relations

Daniel Gatica-Perez, Lakmal Buddika Meegahapola

Diversity-aware platform design is a paradigm that responds to the ethical challenges of existing social media platforms. Available platforms have been criticized for minimizing users' autonomy, marginalizing minorities, and exploiting users' data for prof ...

ASSOC COMPUTING MACHINERY2021

Locally Private Graph Neural Networks

Daniel Gatica-Perez

Graph Neural Networks (GNNs) have demonstrated superior performance in learning node representations for various graph inference tasks. However, learning over graph data can raise privacy concerns when nodes represent people or human-related variables that ...

ASSOC COMPUTING MACHINERY2021

Loud and Trendy: Crowdsourcing Impressions of Social Ambiance in Popular Indoor Urban Places

Daniel Gatica-Perez, Darshan Santani

New research cutting across architecture, urban studies, and psychology is contextualizing the understanding of urban spaces according to the perceptions of their inhabitants. One fundamental construct that relates place and experience is ambiance, which i ...

ACM2015

Check Out This Place: Inferring Ambiance from Airbnb Photos

Daniel Gatica-Perez, Laurent Son Nguyen

Airbnb is changing the landscape of the hospitality industry. For guests, the process of selecting a place to stay is a type of zero-acquaintance situation, and to this day little is known about the inferences that guests make about Airbnb listings. Enviro ...

2018