Modeling Interdependent and Periodic Real-World Action Sequences

Mobile health applications, including those that track activities such as exercise, sleep, and diet, are becoming widely used. Accurately predicting human actions is essential for targeted recommendations that could improve our health and for personalization of these applications. However, making such predictions is extremely difficult due to the complexities of human behavior, which consists of a large number of potential actions that vary over time, depend on each other, and are periodic. Previous work has not jointly modeled these dynamics and has largely focused on item consumption patterns instead of broader types of behaviors such as eating, commuting or exercising. In this work, we develop a novel statistical model for Time-varying, Interdependent, and Periodic Action Sequences. Our approach is based on personalized, multivariate temporal point processes that model time-varying action propensities through a mixture of Gaussian intensities. Our model captures short-term and long-term periodic interdependencies between actions through Hawkes process-based self-excitations. We evaluate our approach on two activity logging datasets comprising 12 million actions taken by 20 thousand users over 17 months. We demonstrate that our approach allows us to make successful predictions of future user actions and their timing. Specifically, our model improves predictions of actions, and their timing, over existing methods across multiple datasets by up to 156%, and up to 37%, respectively. Performance improvements are particularly large for relatively rare and periodic actions such as walking and biking, improving over baselines by up to 256%. This demonstrates that explicit modeling of dependencies and periodicities in real-world behavior enables successful predictions of future actions, with implications for modeling human behavior, app personalization, and targeting of health interventions.Comment: Accepted at WWW 201

An International Study in Competency Education: Postcards from Abroad

Acknowledging that national borders need not constrain our thinking, we have examined a selection of alternative academic cultures and, in some cases, specific schools, in search of solutions to common challenges we face when we consider reorganizing American schools. A wide range of interviews and e-mail exchanges with international researchers, government officials and school principals has informed this research, which was supplemented with a literature review scanning international reports and journal articles. Providing a comprehensive global inventory of competency-based education is not within the scope of this study, but we are confident that this is a representative sampling. The report that follows first reviews the definition of competency-based learning. A brief lesson in the international vocabulary of competency education is followed by a review of global trends that complement our own efforts to improve performance and increase equitable outcomes. Next, we share an overview of competency education against a backdrop of global education trends (as seen in the international PISA exams), before embarking on an abbreviated world tour. We pause in Finland, British Columbia (Canada), New Zealand and Scotland, with interludes in Sweden, England, Singapore and Shanghai, all of which have embraced practices that can inform the further development of competency education in the United States

Evaluation of a personalized digital library based on cognitive styles: Adaptivity vs. adaptability

Personalization can be addressed by adaptability and adaptivity, which have different advantages and disadvantages. This study investigates how digital library users react to these two techniques. More specifically, we develop a personalized digital library to suit the needs of different cognitive styles based on the findings of our previous work (Frias-Martinez, et al., in press). The personalized digital library includes two versions: adaptive version and adaptable version. The results showed that users not only performed better in the adaptive version, but also they perceived more positively to the adaptive version. In addition, cognitive styles have great effects on users’ responses to adaptability and adaptivity. These results provide guidance for designers to select suitable techniques to develop personalized digital libraries

Personalization via collaboration in web retrieval systems: a context based approach

World Wide Web is a source of information, and searches on the Web can be analyzed to detect patterns in Web users' search behaviors and information needs to effectively handle the users' subsequent needs. The rationale is that the information need of a user at a particular time point occurs in a particular context, and queries are derived from that need. In this paper, we discuss an extension of our personalization approach that was originally developed for a traditional bibliographic retrieval system but has been adapted and extended with a collaborative model for the Web retrieval environment. We start with a brief introduction of our personalization approach in a traditional information retrieval system. Then, based on the differences in the nature of documents, users and search tasks between traditional and Web retrieval environments, we describe our extensions of integrating collaboration in personalization in the Web retrieval environment. The architecture for the extension integrates machine learning techniques for the purpose of better modeling users' search tasks. Finally, a user-oriented evaluation of Web-based adaptive retrieval systems is presented as an important aspect of the overall strategy for personalization

Investigation of behavior and perception of digital library users: A cognitive style perspective

Cognitive style is an influential factor in users’ information seeking. The study presented in this paper examines how users’ cognitive styles affect their behavior and perception in digital libraries. Fifty participants took part in this study. Two dimensions of cognitive styles were considered: (a) Field Dependence/Independence; (2) Verbalizer/Imager. The results showed that Intermediate users and Verbalizers have not only more positive perception, but they also complete the tasks in effective ways. Implications for the design of personalized digital libraries are also discussed

Towards a Re-Definition of Government Interpreters' Agency Against a Backdrop of Sociopolitical and Cultural Evolution: A Case of Premier's Press Conferences in China

The sociopolitical and cultural evolution as a result of the Reform and Opening up in 1978, facilitated not least by the inexorable juggernaut of globalization and technological advancement, has revolutionized the way China engages domestically and interacts with the outside world. The need for more proactive diplomacy and open engagement witnessed the institutionalization of the interpreter-mediated premier's press conferences. Such a discursive event provides a vital platform for China to articulate its discourse and rebrand its image in tandem with the profound changes signaled by the Dengist reform. This chapter investigates critically how political press conference interpreting and interpreters' agency in China are impacted in relation to such dramatic transformations. It is revealed that, while interpreters are confronted with seemingly conflicting expectations, in actual practice they are often able to negotiate a way as highly competent interpreting professionals with the additional missions of advancing China's global engagement and safeguarding China's national interests

Towards a Re-Definition of Government Interpreters' Agency Against a Backdrop of Sociopolitical and Cultural Evolution: A Case of Premier's Press Conferences in China

The sociopolitical and cultural evolution as a result of the Reform and Opening up in 1978, facilitated not least by the inexorable juggernaut of globalization and technological advancement, has revolutionized the way China engages domestically and interacts with the outside world. The need for more proactive diplomacy and open engagement witnessed the institutionalization of the interpreter-mediated premier's press conferences. Such a discursive event provides a vital platform for China to articulate its discourse and rebrand its image in tandem with the profound changes signaled by the Dengist reform. This chapter investigates critically how political press conference interpreting and interpreters' agency in China are impacted in relation to such dramatic transformations. It is revealed that, while interpreters are confronted with seemingly conflicting expectations, in actual practice they are often able to negotiate a way as highly competent interpreting professionals with the additional missions of advancing China's global engagement and safeguarding China's national interests