Juan Domingo Velasquez

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Verified

Juan verified their affiliation via an institutional email.

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• PhD
• Professor (Full) at University of Chile

Understanding how demographic factors influence visual attention is crucial for the development of adaptive and user-centered web interfaces. This paper presents a gender-aware saliency prediction system based on fine-tuned deep learning models and demographic-specific gaze behavior. We introduce the WIC640 dataset, which includes 640 web page scre...

Artificial intelligence (AI) techniques are increasingly employed in mental health for remote patient monitoring, enabling the prediction of vital signs and classification of physical activities, which are essential for proactive patient care. However, the black-box nature of deep learning models limits their explainability, a critical factor in cl...

Published paper: https://aging.jmir.org/2025/1/e71936 Accepted Pre-print available at: https://preprints.jmir.org/preprint/71936/accepted

The classification of job postings into standardized occupational categories is a challenging task due to the unstructured, heterogeneous, and noisy nature of labor market data. This process is particularly relevant for labor market analysis conducted by government agencies and employment services, which require accurate and consistent occupational...

Rankability differs fundamentally from ranking: while ranking produces a deterministic ordering that may vary slightly based on data feature importance, rankability serves as a measurement function that quantifies the confidence in an obtained ranking. Evaluating a ranking method is inherently challenging, and assessing rankability is even more com...

Antecedentes: En Chile el proceso de envejecimiento acelerado sin un adecuado control de los factores de riesgo de salud ha provocado un aumento de las enfermedades crónicas y de los años vividos con discapacidad entre las personas mayores. En Chile, el impacto de los programas para la prevención y manejo de estas condiciones ha sido limitado, posi...

Multimodal medical data fusion has emerged as a transformative approach in smart healthcare, enabling a comprehensive understanding of patient health and personalized treatment plans. In this paper, a journey from data, information, and knowledge to wisdom (DIKW) is explored through multimodal fusion for smart healthcare. A comprehensive review of...

Nowadays, there is a broad range of methods for detecting and evaluating executive dysfunction ranging from clinical interview to neuropsychological evaluation. Nevertheless, a critical issue of these assessments is the lack of correspondence of the neuropsychological test's results with real-world functioning. This paper proposes serious games as...

Digital face manipulation has become a concern in the last few years due to its harmful impacts on society. It is especially concerning for high-profile celebrities because their identities can be easily manipulated using mobile or web applications such as FaceSwap and FaceApp. These manipulated faces are so close to real ones that it becomes reall...

Machine translation is a popular automation approach for translating texts between different languages. Although traditionally it has a strong focus on natural language, images can potentially provide an additional source of information in machine translation. However, there are presently two challenges: (i) the lack of an effective fusion method t...

Since its origins, medicine has been more linked to the cure of diseases than to their prevention. This is due to multiple factors, training of health professionals aimed at curing diseases, lack of quality data, processing capacity, poor multidisciplinary approach, etc. However, this paradigm is changing, focusing on maintaining the health of indi...

Disease prediction from diagnostic reports and pathological images using artificial intelligence (AI) and machine learning (ML) is one of the fastest emerging applications in recent days. Researchers are striving to achieve near-perfect results using advanced hardware technologies in amalgamation with AI and ML based approaches. As a result, a larg...

Compared to other features of the human body, voice is quite complex and dynamic, in a sense that a speech can be spoken in various languages with different accents and in different emotional states. Recognizing the gender, i.e. male or female from the voice of an individual, is by all accounts a minor errand for human beings. Similar goes for spea...

The rapid developments in Artificial Intelligence present an opportunity for the research community to provide and advance Smart Health for the well-being of our society. By considering the availability of multi-source information and heterogeneous data in the era of Big Data, this Special Issue explores the theories, methodologies and possible bre...

Millions of women, worldwide, suffer from breast cancer and a large number of them succumb to death. In recent years, computer-aided diagnosis (CAD) systems are being developed for the detection of Breast Cancer. A number of fusion techniques have been proposed in this domain, but none of them take into consideration the decisions taken by a subset...

The outbreak of a global pandemic called coronavirus has created unprecedented circumstances resulting into a large number of deaths and risk of community spreading throughout the world. Desperate times have called for desperate measures to detect the disease at an early stage via various medically proven methods like chest computed tomography (CT)...

The ongoing pandemic due to coronavirus disease, commonly abbreviated as COVID-19, has unleashed a major health crisis across the world. Although multiple vaccines have emerged, large scale vaccination remains a major challenge, especially in developing nations. As a result, early detection still remains a crucial aspect of containing the spread of...

Organ shortage for transplantation is one of the most challenging problems for modern medicine that affects all the world. While Spain, organ donation leader, registered 48.9 donors per million population on 2019, Chile only registered 10.4,which is less that the globe’s average. While Spain has put its efforts in improving procurement process, Chi...

Computational Social Science (CSS) is the use of Web Intelligence and the tools and technology capable of monitoring, analyzing, diagnosing, and resolving day-to-day problems of society. CSS is the development of intelligent systems and solutions to address the critical problems of the society such as poverty and hunger, slavery and torture, diseas...

Background: non-pharmacological interventions to prevent delirium are useful in hospitalised older adults. However, they are poorly implemented in clinical practice. We aimed to develop a software for bedside use by hospitalised older adults and to improve their access to these interventions. Methods: a transdisciplinary team composed of healthc...

The impact that connected community have on precision health or medicine and vice versa offers opportunities for any type of research and survey information, e. g, to predict trends in health-related issues, specifically people behavior towards drug use. Here, precision medicine influences the way to treat the information and get a better outcome t...

Plagiarism is turning in someone else’s work as yourown. Though tools exist for checking the originality of texts,those do not work with images, which can be plagiarized as well.In previous works, we have developed the Docode plagiarismdetection system, which works with text, but, as commercialrequirements have evolved, it is necessary for it to be...

Plagiarism refers to the appropriation of someone else’s ideas and expression. Its ubiquity makes it necessary to counter it, and invites the development of commercial systems to do so. In this document we introduce Docode 5, a system for plagiarism detection that can perform analyses on the World Wide Web and on user-defined collections, and can b...

The assessment of functional status is a critical component of clinical neuropsychological evaluations used for both diagnostic and therapeutic purposes in patients with cognitive brain disorders. There are, however, no widely adopted neuropsychological tests that are both ecologically valid and easily administered in daily clinical practice. This...

Today online social networks seem to be good tools to quickly monitor what is going on with the population, since they provide environments where users can freely share large amounts of information related to their own lives. Due to well known limitations of surveys, this novel kind of data can be used to get additional real time insights from peop...

In this paper a novel approach for analyzing web user behavior and preferences on a web site is introduced, consisting of a physiological-based analysis for the assessment of a web users' click intention, by merging pupil dilation and electroencephalogram (EEG) responses. First, we conducted an empirical study using five real web sites from which t...

Throughout the years having knowledge of Web users’ interests, navigational actions and preferences has gained importance due to the objectives of organizations and companies. Traditionally this field has been studied from the Web Mining perspective, particularly through the Web Usage Mining (WUM) concept, which consists of the application of machi...

Given its complexity, understanding the behavior of users on the Web has been one of the most challenging tasks for data mining-related fields. Historically, most of the approaches have considered web logs as the main source of data. This has led to several successful cases, both in industry and academia, but has also presented several issues and l...

In this work, a new approach for analysing the Web user behavior is introduced, consisting of a physiological-based click intention assessment, based on pupil dilation and electroencephalogram (EEG) responses evaluation. For this, an empirical study was conducted, where the mentioned responses of 21 subjects were recorded while performing diverse i...

Identifying the salient zones from Web interfaces, namely the Website Key Objects, is an essential part of the personalization process that current Web systems perform to increase user engagement. While several techniques have been proposed, most of them are focused on the use of Web usage logs. Only recently has the use of data from users׳ biologi...

We propose a biological-based feature comparison for identifying salient Web objects. We compare several features extracted from eye tracking and EEG data with a baseline given by mean fixation impact introduced by Buscher. For this, we performed an experiment with 20 healthy subjects in which gaze position, pupil size and brain activity were recor...

Interest in Opinion Mining has been growing steadily in the last years, mainly because of its great number of applications and the scientific challenge it poses. Accordingly, the resources and techniques to help tackle the problem are many, and most of the latest work fuses them at some stage of the process. However, this combination is usually exe...

Plagiarism refers to the act of presenting external words, thoughts, or ideas as one’s own, without providing references to the sources from which they were taken. The exponential growth of different digital document sources available on the Web has facilitated the spread of this practice, making the accurate detection of it a crucial task for educ...

Resumen Se propone un nuevo enfoque para predecir la intención de click del usuario Web, usando datos de dilatación pupilar generados por un dispo-sitivo de eye-tracking. El objetivo es determinar si esta variable permite diferenciar estados de elección y no-elección de objetos Web, y de ser así, generar un modelo de clasificación para predecir la...

Abstract—We propose a novel approach for predicting Web user click intention, using pupil dilation data generated by an eye-tracking device as input. Our goal is to determine if this variable is useful to differentiate choice and no-choice states, and if so, to generate a classification model for predicting choice understood as a click. For this, w...

This work proposes an extension of Bing Liu’s aspect-based opinion mining approach in order to apply it to the tourism domain. The extension concerns with the fact that users refer differently to different kinds of products when writing reviews on the Web. Since Liu’s approach is focused on physical product reviews, it could not be directly applied...

This paper introduces a framework for trend modeling and detection on the Web through the usage of Opinion Mining and Topic Modeling tools based on the fusion of freely available information. This framework consists of a four step model that runs periodically: crawl a set of predefined sources of documents; search for potential sources and extract...

In this paper, a novel approach is introduced to compare web sites by analysing their web page content. Each web page can be expressed as a set of entities called MicroGenres, which in turn are abstractions about design patterns and genres for representing the page content. This description is useful for web page and web site classification and for...

We propose a graph-based analysis framework to study the dynamics of visual gaze from web users. Our goal is to extract the main characteristics of the information foraging process from an attention-centric perspective. Our approach consists of modeling web objects, such as images and paragraphs, as nodes. The visual transitions are represented as...

The high penetration of Twitter in Chile has favored the use of this social network for companies and brands to get additional information on user opinions and feedback about their products and services. In recent years there have been many studies to determine the polarity of a comment on Twitter mainly considering three classes: positive, negativ...

In this paper we describe the algorithms and tools offered by DOCODE, a system for plagiarism detection in educational institutions, with a special focus on the task of external plagiarism detection using the Web as a source of information. In that context, although DOCODE is a full-featured system based on several algorithms, our main contribution...

Web usage mining has proven to be an important advance for e-business systems, both by finding web user buying patterns and suggesting ways to improve web user navigation. A primary input for web usage mining is web user sessions that must be constructed from web server logs called sessionization when such sessions are not otherwise identified. We...

This paper introduces a framework for trend modeling and detection on the Web through the usage of Opinion Mining and Topic Modeling tools based on the fusion of freely available information. This framework consists of a four step model that runs periodically: crawl a set of predefined sources of documents; search for potential sources and extract...

In this paper, we propose OpinionZoom, a modular software that helps users in an easy manner to understand the vast amount of tourism opinions disposed all over the Web. We also successfully implemented and tested OpinionZoom, encompassing the situation of the tourism industry in Los Lagos, also known as the Lake District, in Chile. Results showed...

Web mining is a concept that gathers all techniques, methods and algorithms used to extract information and knowledge from data originating on the web (web data). A part of this technique aims to analyze the behavior of users in order to continuously improve both the structure and content of visited web sites. Behind this quite altruistic belief –...

In this study we extend Bing Liu’s aspect-based opinion mining technique to apply it to the tourism domain. Using this extension, we also offer an approach for considering a new alternative to discover consumer preferences about tourism products, particularly hotels and restaurants, using opinions available on the Web as reviews. An experiment is a...

Delivery of efficient service through a web site makes it compulsory in the redesigning stage to take into account the behavior of the users, which can be studied by means of a web log file that partially records information about user visits. The reconstruction of all of the sequences of pages that are visited by users who browse a web site is kno...

This paper introduces a novel approach for collecting and processing data originated by web user ocular movements on a web page, which are captured by using an eye-tracking tool. These data allow knowing the exact web user's eye position on a computer screen, and by combining them with the sequence of web page visits registered in the web log, sign...

In this paper we give evidence that it is possible to characterize and detect those potential users of false invoices in a given year, depending on the information in their tax payment, their historical performance and characteristics, using different types of data mining techniques. First, clustering algorithms like SOM and neural gas are used to...

Web usage have been studied from the point of view of machine learning. Although web usage prediction are mostly restricted to an static web site structure, hence this results to be a hard restriction to accomplish in the practice. We propose a decision-making model that allow predicting web users’ navigation choices even in dynamics web sites. We...

The retrieval of similar documents in the Web from a given document is different in many aspects from information retrieval based on queries generated by regular search engine users. In this work, a new method is proposed for Web similarity document retrieval based on generative language models and meta search engines. Probabilistic language models...

End users leave traces of behavior all over the Web all times. From the explicit or implicit feedback of a multimedia document or a comment in an online social network, to a simple click in a relevant link in a search engine result, the information that we as users pour into the Web defines its actual representation, which is independent for each u...

Web Opinion Mining (WOM) is a new concept in Web Intelligence. It embraces the problem of extracting, analyzing and aggregating web data about opinions. Studying users’ opinions is relevant because through them it is possible to determine how people feel about a product or service and know how it was received by the market. In this chapter, we show...

Web usage mining is the process of extracting patterns from web user's preferences and browsing behavior. Furthermore, the web user behavior refers to the user's activities in a web site. Cognitive science is a multi-disciplinary approach used for the understanding of human behavior, whose aims is to develop models of information processing in the...

This paper introduces the utilization of data originated in the web user ocular movement to improve the methodology for identifying Website Keyobjects that was designed by Velásquez and Dujovne through the use of eye tracking tools. Given a website, this methodology takes as input the request register (Web log) of the website, the pages that compos...

An ant colony optimization-based algorithm to predict web usage patterns is presented. Our methodology incorporates multiple data sources, such as web content and structure, as well as web usage. The model is based on a continuous learning strategy based on previous usage in which artificial ants try to fit their sessions with real usage through th...

The construction of a web site is a great challenge that integrates different elements such as the hyperlink structure, colors, pictures, movies and textual contents. In the latter, the correct textual content can be the key to attracting users to visit the site. In fact, many users visit a web site by using a web search engine such as, for example...

The present work describes a novel approach by applying a neurophysiological theory of decision making for describing web user browsing behavior. A dynamic stochastic model of the decision making process is proposed. Such a model is based on the Leaky Competing Accumulator (LCA) model of neurophysiology. It describes the neural activity of differen...

The analysis of human behaviour has been conducted within diverse disciplines, such as psychology, sociology, economics, linguistics, marketing and computer science. Hence, a broad theoretical framework is available, with a high potential for application into other areas, in particular to the analysis of web user browsing behaviour. The above menti...

Web Opinion Mining (WOM) is a new concept in Web Intelligence.It embraces the problem of extracting, analyzing and aggregating web data aboutopinions. Studying users’ opinions is relevant because through them it is possible todetermine how people feel about a product or service and know how it was receivedby the market. In this chapter, we show an...

Web mining has been traditionally used in different application domains in order to enhance the content that Web users are accessing. Likewise, Website administrators are interested in finding new approaches to improve their Website content according to their users preferences. Furthermore, the Semantic Web has been considered as an alternative to...

The retrieval of similar documents from the Web using documents as input instead of key-term queries is not currently supported by traditional Web search engines. One approach for solving the problem consists of fingerprint the document's content into a set of queries that are submitted to a list of Web search engines. Afterward, results are merged...

Plagiarism detection, one of the main problems that educational institutions have been dealing with since the massification of Internet, can be considered as a classification problem using both self-based information and text processing algorithms whose computational complexity is intractable without using space search reduction algorithms. First,...

Reading comprehension is one of the main concerns for educational institutions, as it forges the students' ability to comprehend and learn accurately a given information source (e.g. textbooks, articles, papers, etc.). However, there are few approaches that integrates digital sources of educational information with automated systems to detect wheth...

In this paper we propose a novel methodology for analyzing web user behavior based on session simulation by using an Ant Colony Optimization algorithm which incorporates usage, structure and content data originating from a real web site. In the first place, artificial ants learn from a clustered web user session set through the modification of a te...

Today and years to come, one of the most challenging problems of the global economy is to keep maintaining and developing the correct balance of the environment from which resources are extracted. For this, we believe that Information Systems and formal methodologies for sustainability measures definition are related to decision making and manageme...

Enhancing the content and structure of a web site is a very important task which can help to maintain people visiting a web site and gain new visits (or customers). Web mining area helps to enhance a web site organization and contents using data mining algorithms. In particular we may perform Web Mining using a Self Organizing Feature Map (SOFM or...

Plagiarism detection has been considered as a classification problemwhich can be approximated with intrinsic strategies, considering self-based infor-mation from a given document, and external strategies, considering comparisontechniques between a suspicious document and different sources. In this work,both intrinsic and external approaches for pla...

Abstract Plagiarism detection has been considered as a classification problem which can be approximated with intrinsic strategies, considering self-based infor-mation from a given document, and external strategies, considering comparisontechniques between a suspicious document and different sources. In this work,both intrinsic and external approach...

Nowadays, plagiarism has been presented as one of the main distresses that the information technology revolution has lead into our society for which using pattern matching algorithms and intelligent data analysis approaches, these practices could be identified. Furthermore, a fast document copy detection algorithm could be used in large scale appli...