Recommender systems based on methods such as collaborative and content-based filtering rely on extensive user profiles and item descriptors as well as on an extensive history of user preferences. Such methods face a number of challenges; including the cold-start problem in systems characterized by irregular usage, privacy concerns, and contexts where the range of indicators representing user interests is limited. We describe a recommender algorithm that builds a model of collective preferences independently of personal user interests and does not require a complex system of ratings. The performance of the algorithm is analyzed on a large transactional data set generated by a real-world dietary intake recall system.

Despite the divisive nature of abortion within the Republic of Ireland and Northern Ireland, where access to safe, legal abortion is severely restricted, effecting legislative reform demands widespread public support. In light of a building pro-choice counter-voice, this work contributes to a growing body of HCI research that takes an activist approach to design. We report findings from four design workshops with 31 pro-choice stakeholders across Ireland in which we positioned an exploratory protosite, HerStoryTold, to engender critical conversations around the use of sensitive abortion narratives as a tool for engagement. Our analysis shows how digital storytelling can help reject false narratives and raise awareness of the realities of abortion laws. It suggests design directions to curate narratives that provoke empathy, foster polyvocality, and ultimately expand the engaged community. Furthermore, this research calls for designers to actively support community mobilization through providing 'stepping stones' to activism.

Group Spinner is a digital visual tool intended to help teachers observe and reflect on children's collaborative technology-enhanced learning activities in the classroom. We describe the design of Group Spinner, which was informed by activity theory, previous work and teachers' focus group feedback. Based on a radar chart and a set of indicators, Group Spinner allows teachers to record in-class observations as to different aspects of group learning and learning behaviors, beyond the limited knowledge acquisition measures. Our exploratory study involved 6 teachers who used the tool for a total of 23 classes in subjects ranging from Maths and Geography to Sociology and Art. Semi-structured interviews with these teachers revealed a number of different uses of the tool. Depending on their experience and pedagogy, teachers considered Group Spinner to be a valuable tool to support awareness, reflection, communication, and/or planning.