Home

Person

Daniel Gatica-Perez

About
Privacy
Disclaimer

Graph Chatbot

Related publications (110)

Page 5 of 6

Special Section on Social Media as Sensors

Daniel Gatica-Perez, Jie Luo

Social media have transformed the Web into an interactive sharing platform where users upload data and media, comment on, and share this content within their social circles. Each content item is associated with an abundance of metadata and related informat ...

Ieee-Inst Electrical Electronics Engineers Inc2013

ProGAP: Progressive Graph Neural Networks with Differential Privacy Guarantees

Daniel Gatica-Perez, Sina Sajadmanesh

Graph Neural Networks (GNNs) have become a popular tool for learning on graphs, but their widespread use raises privacy concerns as graph data can contain personal or sensitive information. Differentially private GNN models have been recently proposed to p ...

Assoc Computing Machinery2024

Estimating Dominance in Multi-Party Meetings Using Speaker Diarization

Daniel Gatica-Perez

With the increase in cheap commercially available sensors, recording meetings is becoming an increasingly practical option. With this trend comes the need to summarize the recorded data in semantically meaningful ways. Here, we investigate the task of auto ...

2011

Tracking the visual focus of attention for a varying number of wandering people

Daniel Gatica-Perez, Jean-Marc Odobez, Kevin Smith, Silèye Oumar Ba

In this article, we define and address the problem of finding the visual focus of attention for a varying number of wandering people (VFOA-W) -- determining where a person is looking when their movement is unconstrained. VFOA-W estimation is a new and impo ...

2008

Keep Sensors in Check: Disentangling Country-Level Generalization Issues in Mobile Sensor-Based Models with Diversity Scores

Daniel Gatica-Perez, Lakmal Buddika Meegahapola

Machine learning models trained with passive sensor data from mobile devices can be used to perform various inferences pertaining to activity recognition, context awareness, and health and well-being. Prior work has improved inference performance through t ...

Assoc Computing Machinery2023

A Tale of Two Interactions: Inferring Performance in Hospitality Encounters from Cross-Situation Social Sensing

Daniel Gatica-Perez, Skanda Muralidhar

2018

Development of the Geographical Proportional-to-size Street-Intercept Sampling (GPSIS) method for recruiting urban nightlife-goers in an entire city

Daniel Gatica-Perez, Darshan Santani

We developed the Geographical Proportional-to-size Street-Intercept Sampling (GPSIS) method in order to obtain a sample of nightlife-goers which accounted for the diversity of spaces, patrons and locations within two Swiss cities. Popular nightlife zones w ...

2017

Trust Indicators and Explainable AI: A Study on User Perceptions

Hélène Michelle Portier, Daniel Gatica-Perez, Nicolas Henchoz, Delphine Ribes Lemay, Andreas Sonderegger, Lara Jacqueline Défayes, Thanh Trung Phan

Nowadays, search engines, social media or news aggregators are the preferred services for news access. Aggregation is mostly based on artificial intelligence technologies raising a new challenge: Trust has been ranked as the most important factor for media ...

Springer2021

DiversityOne: A Multi-Country Smartphone Sensor Dataset for Everyday Life Behavior Modeling

Daniel Gatica-Perez

Understanding everyday life behavior of young adults through personal devices, e.g., smartphones and smartwatches, is key for various applications, from enhancing the user experience in mobile apps to enabling appropriate interventions in digital health ap ...

ASSOC COMPUTING MACHINERY2025

Modeling and Understanding Flickr Communities through Topic-based Analysis

Daniel Gatica-Perez, Radu Andrei Negoescu

With the increased presence of digital imaging devices there also came an explosion in the amount of multimedia content available online. Users have transformed from passive consumers of media into content creators and have started organizing themselves in ...

2010

Shooting shots: Estimating alcoholic drink sizes in real life using event-level reports and annotations of close-up pictures

Daniel Gatica-Perez, Thanh Trung Phan

Introduction and Aims Drinks consumed in real life are diverse, in terms of beverage type, container size and alcohol by volume. To date, most ecological momentary assessment studies have assessed drinking amounts with 'standard' drinks, although their eve ...

WILEY2021

Smartphone Sensing for the Well-being of Young Adults: A Review

Daniel Gatica-Perez, Lakmal Buddika Meegahapola

Over the years, mobile phones have become versatile devices with a multitude of capabilities due to the plethora of embedded sensors that enable them to capture rich data unobtrusively. In a world where people are more conscious regarding their health and ...

2021

From big smartphone data to worldwide research: The Mobile Data Challenge

Daniel Gatica-Perez, Olivier Dousse, Imad Aad, Julien Eberle

This paper presents an overview of the Mobile Data Challenge (MDC), a large-scale research initiative aimed at generating innovations around smartphone-based research, as well as community-based evaluation of mobile data analysis methodologies. First, we r ...

Elsevier Science Bv2013

Mining group nonverbal conversational patterns using probabilistic topic models

Daniel Gatica-Perez, Dinesh Babu Jayagopi

The automatic discovery of group conversational behavior is a relevant problem in social computing. In this paper, we present an approach to address this problem by defining a novel group descriptor called bag of group-nonverbal-patterns defined on brief o ...

2010

Insiders and Outsiders: Comparing Urban Impressions between Population Groups

Daniel Gatica-Perez, Darshan Santani

There is a growing interest in social and urban computing to employ crowdsourcing as means to gather impressions of urban perception for indoor and outdoor environments. Previous studies have established that reliable estimates of urban perception can be o ...

ACM2017

Declarative Variables in Online Dating: A Mixed-Method Analysis of a Mimetic-Distinctive Mechanism

Daniel Gatica-Perez, Jessica Carolina Pidoux

Declarative variables of self-description have a long-standing tradition in matchmaking media. With the advent of online dating platforms and their brand positioning, the volume and semantics of variables vary greatly across apps. However, a variable lands ...

2021

Generative AI Literacy: Twelve Defining Competencies

Ravinithesh Reddy Annapureddy, Daniel Gatica-Perez

This article introduces a competency-based model for generative artificial intelligence (AI) literacy covering essential skills and knowledge areas necessary to interact with generative AI. The competencies range from foundational AI literacy to prompt eng ...

2025

Contextual classification of image patches with latent aspect models

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

We present a novel approach for contextual classification of image patches in complex visual scenes, based on the use of histograms of quantized features and probabilistic aspect models. Our approach uses context in two ways: (1) by using the fact that spe ...

2009

Framing the News: From Human Perception to Large Language Model Inferences

Daniel Gatica-Perez

Identifying the frames of news is important to understand the articles' vision, intention, message to be conveyed, and which aspects of the news are emphasized. Framing is a widely studied concept in journalism, and has emerged as a new topic in computing, ...

Assoc Computing Machinery2023

InnerView: Learning Place Ambiance from Social Media Images

Daniel Gatica-Perez, Darshan Santani, Rui Hu

In the recent past, there has been interest in characterizing the physical and social ambiance of urban spaces to understand how people perceive and form impressions of these environments based on physical and psychological constructs. Building on our earl ...

ACM2016