Glívia Angélica Rodrigues Barbosa

Privacy for Children and Teenagers on Social Networks from a Usability Perspective: A Case Study on Facebook

Children and teenagers comprise a user group particularly susceptible to privacy infringement risks in Online Social Networks (OSNs). In this sense, the usability of privacy controls should be appropriate to such users. This study aims to characterize, through a case study on Facebook, how children and teenagers deal with privacy features on OSNs and whether the available privacy controls help this user group to manage the privacy levels of their personal data. The case study considered children and teenagers in Brazil, the top-3 country on the number of Facebook users. The results indicated that there are usability violations that hinder this group from adjusting privacy settings, compromising its privacy and security on OSNs. These results are relevant and not limited to the context of Brazil, because they warn us about the vulnerability of children and teenagers on OSNs, as well as they evince the role of usability in privacy controls.

Beyond the Stars: Towards a Novel Sentiment Rating to Evaluate Applications in Web Stores of Mobile Apps

This paper proposes an approach to evaluate mobile applications which complements the information provided by the number of stars and downloads in app stores. The goal is to provide novel information to assist users in the decision-making process regarding the choice of applications. In this sense, we conducted experiments to verify the relationship between the number of stars and the content of review comments. Results indicated that there is information in reviews not properly represented by stars. Thus, we present a sentiment rating generated automatically by aggregating opinions reported in the reviews related to each application. We evaluated this new rating using 26,996 reviews related to six applications present on the Google Play Store. The obtained results allow us to demonstrate that: (1) it is possible and feasible to generate a sentiment rating automatically and (2) the rating is useful for web stores of mobile applications to improve their mechanisms of ranking and recommendation as well as to assist users and developers to evaluate the quality and/or acceptance of the offered mobile applications.

Game accessibility guidelines for people with sequelae from macular chorioretinitis

Abstract Macular chorioretinitis is an ocular inflammation that may cause the permanent loss of the central vision. Researches indicate that the formation of macular scars, the potential sequela of that inflammation, is the leading cause of low vision in children. As we found no game accessibility guidelines in the literature that were specific to users with central vision loss in a preliminary review, this study thus aimed at surveying guidelines targeted at players with low vision. They were extracted through a systematic literature review conducted on digital libraries. There were some known guidelines that were not in the results of the systematic literature review and therefore we made a manual selection of other relevant sources. We also proposed a new guideline related to the sharpness of images because it was deemed important to improve game accessibility to the public concerned and it had not been presented in the literature. In total, we identified 25 general game accessibility guidelines for people with low vision, plus the one we proposed, and 20 of them were considered applicable to people with macular scars. Afterwards, based on classifications available in the literature and on the experience of the authors as developers, we assessed the feasibility of each guideline according to their impact, reach and an estimation of their implementation cost. The survey also confirmed that no guideline existed that was specific to players with central vision loss. In order to evaluate the new guideline and one of those identified in the literature from the player perspective, we developed a game prototype which implemented both. A qualitative analysis conducted with the game prototype indicated that the evaluated guidelines are applicable to the public concerned. We expect the results of this research to serve as a step towards determining how to make games more accessible to players with sequelae from macular chorioretinitis.

Characterization of Public Opinion on Political Events in Brazil Based on Twitter Data

In this work we characterize Brazilian online population sentiment on different political events using data from Twitter and we also discuss the advantages of the usage of this social media as data source. The results demonstrated that the Brazilian population uses Twitter to manifest their political view, expressing both positive and negative sentiments regarding political events. This kind of characterization may contribute to build a critical opinion of Brazilian people, once they would not be limited by what is being divulgated by typical media, such as television and newspapers. Additionally, we reinforced the applicability of social media, as Twitter, to make this kind of characterization.

Characterizing gamification strategies in educational mobile applications: a case study of duolingo

The increasing use of mobile devices has favored the use of mobile apps as a learning tool. With this popularity, one of the concerns of Human Computer Interaction area (HCI) is how to motivate users through the interface and interaction model, to make the continued use of these applications. Consequently, new design strategies have been explored to meet the needs of these users. In this sense, the adoption of gamification strategies has contributed positively to the continued use of mobile applications in the educational domain. Motivated by this scenario, this study aims to evaluate and characterize as Duolingo application, considered one of the best applications for teaching languages, has adopted the gamification strategies and, in fact, these strategies contribute as a motivational factor for application use. The results obtained allowed to observe how the strategies adopted by the designer interface have helped to motivate the continued use of this application and, complementarily, may assist in developing and evaluation of applications that make use of gamification as a motivational factor.