Ana Cristina Garcia

Ana Cristina Garcia


Research Focus & Metrics

Academic Career Length

36Years (1991-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 January 2015 in Sensors
Verified
Journal Article
Open access
PDF file
LMLuis Martí
Luis Martí
NSNayat Sánchez-Pi
Nayat Sánchez-Pi
Jose M. MolinaJose M. Molina
Jose M. Molina
AGAna Cristina Garcia
Ana Cristina Garcia
Anomaly detection is the problem of finding patterns in data that do not conform to an a priori expected behavior. This is related to the problem in which some samples are distant, in terms of a given metric, from the rest of the dataset, where these anomalous samples are indicated as outliers. Anomaly detection has recently attracted the attention of the research community, because of its relevance in real-world applications, like intrusion detection, fraud detection, fault detection and system health monitoring, among many others. Anomalies themselves can have a positive or negative nature, depending on their context and interpretation. However, in either case, it is important for decision makers to be able to detect them in order to take appropriate actions. The petroleum industry is one of the application contexts where these problems are present. The correct detection of such types of unusual information empowers the decision maker with the capacity to act on the system in order to correctly avoid, correct or react to the situations associated with them. In that application context, heavy extraction machines for pumping and generation operations, like turbomachines, are intensively monitored by hundreds of sensors each that send measurements with a high frequency for damage prevention. In this paper, we propose a combination of yet another segmentation algorithm (YASA), a novel fast and high quality segmentation algorithm, with a one-class support vector machine approach for efficient anomaly detection in turbomachines. The proposal is meant for dealing with the aforementioned task and to cope with the lack of labeled training data. As a result, we perform a series of empirical studies comparing our approach to other methods applied to benchmark problems and a real-life application related to oil platform turbomachinery anomaly detection.

24 February 2021 in Artificial Intelligence Review
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Journal Article
Closed access
PDF file
JPJulliano Trindade Pintas
Julliano Trindade Pintas
Leandro A. F. FernandesLeandro A. F. Fernandes
Leandro A. F. Fernandes
AGAna Cristina Garcia
Ana Cristina Garcia

17 May 2023 in AI & SOCIETY
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Journal Article
Open access
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AGAna Cristina Garcia
Ana Cristina Garcia
MGMarcio Gomes Pinto Garcia
Marcio Gomes Pinto Garcia
RRRoberto Rigobon
Roberto Rigobon
The widespread usage of machine learning systems and econometric methods in the credit domain has transformed the decision-making process for evaluating loan applications. Automated analysis of credit applications diminishes the subjectivity of the decision-making process. On the other hand, since machine learning is based on past decisions recorded in the financial institutions’ datasets, the process very often consolidates existing bias and prejudice against groups defined by race, sex, sexual orientation, and other attributes. Therefore, the interest in identifying, preventing, and mitigating algorithmic discrimination has grown exponentially in many areas, such as Computer Science, Economics, Law, and Social Science. We conducted a comprehensive systematic literature review to understand (1) the research settings, including the discrimination theory foundation, the legal framework, and the applicable fairness metric; (2) the addressed issues and solutions; and (3) the open challenges for potential future research. We explored five sources: ACM Digital Library, Google Scholar, IEEE Digital Library, Springer Link, and Scopus. Following inclusion and exclusion criteria, we selected 78 papers written in English and published between 2017 and 2022. According to the meta-analysis of this literature survey, algorithmic discrimination has been addressed mainly by looking at the CS, Law, and Economics perspectives. There has been great interest in this topic in the financial area, especially the discrimination in providing access to the mortgage market and differential treatment (different fees, number of parcels, and interest rates). Most attention has been devoted to the potential discrimination due to bias in the dataset. Researchers are still only dealing with direct discrimination, addressed by algorithmic fairness, while indirect discrimination (structural discrimination) has not received the same attention.

1 October 2015 in Decision Support Systems
Verified
Journal Article
Open access
MKMark Klein
Mark Klein
AGAna Cristina Garcia
Ana Cristina Garcia
Open innovation platforms (web sites where crowds post ideas in a shared space) enable us to elicit huge volumes of potentially valuable solutions for problems we care about, but identifying the best ideas in these collections can be prohibitively expensive and time-consuming. This paper presents an approach, called the \"bag of lemons\", which enables crowd to filter ideas with accuracy superior to conventional (Likert scale) rating approaches, but in only a fraction of the time. The key insight behind this approach is that crowds are much better at eliminating bad ideas than at identifying good ones. an approach for using the crowd to filter ideas submitted in open innovation engagementsincreases filtering accuracy and reduces rater time compared to conventional (5-point Likert scale) approachkey insight: crowds are better at eliminating bad ideas than identifying good ones.

1 January 2005 in Lecture Notes in Computer Science
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Book Chapter
Closed access
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AGAna Cristina Garcia
Ana Cristina Garcia
CMCristiano Maciel
Cristiano Maciel
FPFernando Bicharra Pinto
Fernando Bicharra Pinto

1 April 2004 in Advanced Engineering Informatics
Verified
Journal Article
Closed access
AGAna Cristina Garcia
Ana Cristina Garcia
JKJohn Kunz
John Kunz
MEMartin Ekstrom
Martin Ekstrom
AKArto Kiviniemi
Arto Kiviniemi