Recommender systems are increasingly used in high-risk application domains, including healthcare. It has been shown that explanations are crucial in this context to support decision-making. This paper explores how to explain call recommendations to nursing home staff, providing insights into call priority, notifications, and resident information. We present the design and implementation of a recommender engine and a mobile application designed to support call recommendations and explain these recommendations that may contribute to residents’ safety and quality of care. More specifically, we report on the results of a user-centered design approach with residents (N=12) and healthcare professionals (N=4), and a final evaluation (N=12) after four months of deployment. The results show that our design approach provides a valuable tool for more accurate and efficient decision-making. The overall system encourages nursing home staff to provide feedback and annotate, resulting in more confidence in the system. We discuss usability issues, challenges, and reflections to be considered in future health recommender systems.

Systems involving artificial intelligence (AI) are protagonists in many everyday activities. Moreover, designers are increasingly implementing these systems for groups of users in various social and cooperative domains. Unfortunately, research on personalized recommendation systems often reports negative experiences due to a lack of diversity, control, or transparency. Providing a meta-analysis of the interaction design strategies for group recommendation systems (GRS) offers designers and practitioners a departure to address these issues and imagine new interaction possibilities for this context. Therefore, we systematically reviewed the ACM, IEEE, and Scopus digital libraries to identify GRS interface designs, resulting in a final corpus of 142 academic papers. After a systematic coding process, we used descriptive statistics and thematic analysis to uncover the current state of the art regarding interaction design strategies for GRS in six areas: (1) application domains; (2) devices chosen to implement the systems; (3) prototype fidelity; (4) strategies for profile transparency, justification, control, and diversity; (5) strategies for group formation and final group consensus; and, (6) evaluation methods applied in user studies during the design process. Based on our findings, we present an exhaustive typology of interaction design strategies for GRS and a set of research opportunities to foster human-centered interfaces for personalized recommendations in cooperative and social computing contexts.

Fairness is an important aspect in group recommender systems (GRSs). They must ensure that potentially diverse preferences of all group members are taken into consideration when providing recommendations. Previous work has proposed a number of conflict elicitation and merging techniques to produce preferable recommendations for group members. However, we have yet to understand the influence of user personality on the perception of fairness in GRSs. To examine this gap, we use music recommendation as an example domain. We have developed a web-based group music recommender system using the Spotify API and two simple ranking algorithms: one based on the time the songs were voted by users (time-based) and the other based on a dissimilarity score (dissimilarity-based). A within-subjects experiment was conducted with 45 participants divided into groups of 3 (15 groups). Results showed that openness personality has a negative correlation with the perception that fairness is important in groups.

We have become increasingly reliant on recommender systems to help us make decisions in our daily live. As such, it is becoming essential to explain to users how these systems reason to enable them to correct system assumptions and to trust the system. The advantages of explaining the recommendation process has been shown by a vast amount of research. Additionally, previous studies showed that personality affects users' attitudes, tastes and information processing. However, it is still unclear whether personality has an impact on the way users process and perceive explanations. In this paper, we report the results of a study that investigated differences between personal characteristics of the perception and the gaze pattern of a music recommender interface in the presence and absence of explanations. We investigated the differences between Need For Cognition, Musical Sophistication and the Big Five personality traits. Results show empirical evidence of the differences between Musical Sophistication and Openness on both perception and gaze pattern. We found that users with a high Musical Sophistication and a low Openness score benefit the most from explanations.

Critiquing-based recommender systems aim to elicit more accurate user preferences from users' feedback toward recommendations. However, systems using a graphical user interface (GUI) limit the way that users can critique the recommendation. With the rise of chatbots in many application domains, they have been regarded as an ideal platform to build critiquing-based recommender systems. Therefore, we present MusicBot, a chatbot for music recommendations, featured with two typical critiquing techniques, user-initiated critiquing (UC) and system-suggested critiquing (SC). By conducting a within-subjects (N=45) study with two typical scenarios of music listening, we compared a system of only having UC with a hybrid critiquing system that combines SC with UC. Furthermore, we analyzed the effects of four personal characteristics,musical sophistication (MS), desire for control (DFC), chatbot experience (CE), and tech savviness (TS), on the user's perception and interaction of the recommendation in MusicBot. In general, compared with UC, SC yields higher perceived diversity and efficiency in looking for songs; combining UC and SC tends to increase user engagement. Both MS and DFC positively influence several key user experience (UX) metrics of MusicBot such as interest matching, perceived controllability, and intent to provide feedback.

Recommender systems have been increasingly used in online services that we consume daily, such as Facebook, Netflix, YouTube, and Spotify. However, these systems are often presented to users as a "black box", i.e. the rationale for providing individual recommendations remains unexplained to users. In recent years, various attempts have been made to address this black box issue by providing textual explanations or interactive visualisations that enable users to explore the provenance of recommendations. Among other things, results demonstrated benefits in terms of precision and user satisfaction. Previous research had also indicated that personal characteristics such as domain knowledge, trust propensity and persistence may also play an important role on such perceived benefits. Yet, to date, little is known about the effects of personal characteristics on explaining recommendations. To address this gap, we developed a music recommender system with explanations and conducted an online study using a within-subject design. We captured various personal characteristics of participants and administered both qualitative and quantitative evaluation methods. Results indicate that personal characteristics have significant influence on the interaction and perception of recommender systems, and that this influence changes by adding explanations. For people with a low need for cognition are the explained recommendations the most beneficial. For people with a high need for cognition, we observed that explanations could create a lack of confidence. Based on these results, we present some design implications for explaining recommendations.

The dynamics of the labor market and the tasks with which jobs are being composed are continuously evolving. Job mobility is not evident, and providing effective recommendations in this context has also been found to be particularly challenging. In this paper, we present Labor Market Explorer, an interactive dashboard that enables job seekers to explore the labor market in a personalized way based on their skills and competences. Through a user-centered design process involving job seekers and job mediators, we developed this dashboard to enable job seekers to explore job recommendations and their required competencies, as well as how these competencies map to their profile. Evaluation results indicate the dashboard empowers job seekers to explore, understand, and find relevant vacancies, mostly independent of their background and age.

Music preferences are likely to depend on contextual characteristics such as location and activity. However, most recommender systems do not allow users to adapt recommendations to their current context. We therefore built ContextPlay, a context-aware music recommender that enables user control for both contextual characteristics and music preferences. By conducting a mixed-design study (N=114) with four typical scenarios of music listening, we investigate the effect of controlling contextual characteristics in a music recommender system on four aspects: perceived quality, diversity, effectiveness, and cognitive load. Compared to our baseline which only allows to specify music preferences, having additional control for context leads to higher perceived quality and does not increase cognitive load. We also find that the contexts of mood, weather, and location tend to influence user perception of the system. Moreover, we found that users are more likely to modify contexts and their profile during relaxing activities.

Although gait/balance analysis methods have proven effective for assessing falls risk (FR), they are mostly confined to the laboratory and rely on expensive specialist equipment. Recent sensor technologies have made it possible to capture FR data accurately; however, no exploration has been done on how to effectively communicate these data to seniors in both healthcare and free-living settings. We describe IDA (Insole Device for Assessment of Falls Risk), comprising a relatively inexpensive insole and prototype application that provides feedback to stakeholders. To explore what level of FR data should best be communicated to different stakeholders, we conducted workshops with 26 seniors and interviewed 7 healthcare workers in the UK. We highlight stakeholder preferences on viewing FR data to foster greater understanding of outcomes and enhance communication between stakeholders. Finally, we identify opportunities for design on enhancing understanding of gait/balance outcomes; these have potential applications in other areas of physical rehabilitation.

The "black box'' nature of today's recommender systems raises a number of challenges for users, including a lack of trust and limited user control. Providing more user control is interesting to enable end-users to help steer the recommendation process with additional input and feedback. However, different users may have different preferences with regard to such control. To the best of our knowledge, no research has investigated the effect of personal characteristics on visual control techniques in the music recommendation domain. In this paper, we present results of a user study on the web using two different visualisation techniques (a radar chart and sliders) that allows users to control Spotify recommendations. A within-subject design withLatin Square counterbalancing measures was used for the study. Results indicate that the radar chart helped the participants discover a significantly higher number of new songs compared to the sliders. We also found that users' experience with Spotify had an influence on their interaction with different musical attributes. The participants who used Spotify frequently and users with a high individual musical sophistication interacted with the attributes significantly more with the radar chart compared to the sliders. Individual musical sophistication also had a significant impact on their interaction with the interaction techniques. The participants with high musical sophistication interacted significantly more with the radar chart in comparison to the sliders. Based on the feedback from our participants, we provide design suggestions to further improve user control in music recommendation.

A great deal of research into Collaborative Information Retrieval (CIR) has assumed that search team members have the same level of unrestricted access to information. However, case studies and observations from different domains including government, healthcare and legal, have suggested that CIR sometimes involves people with unequal access to information. This type of scenario has been referred to as Multi-Level CIR (MLCIR). In addition to supporting collaboration, MLCIR systems must ensure that there is no unintended disclosure of sensitive information, this is an under investigated area of research. In this paper we present results of an evaluation of an interface we have designed for MLCIR scenarios. Pairs of participants used the interface under 3 different information access scenarios for a variety of search tasks. These scenarios included 1 CIR and 2 MLCIR scenarios, namely: full access (FA), document removal (DR) and term blacklisting (TR). Design interviews were conducted post evaluation to obtain qualitative feedback from participants. Evaluation results showed that our interface performed well for both DR and FA scenarios but for TR, team members with less access had a negative influence on their partner's search performance, demonstrating insights into how different MLCIR scenarios should be supported. Design interview results showed that our interface helped the participants to reformulate their queries, understand their partner's performance, reduce duplicated work and review their team's search history without disclosing sensitive information.

The majority of research in Collaborative Information Retrieval (CIR) has assumed that collaborating team members have uniform information access. However, practice and research has shown that there may not always be uniform information access among team members, e.g. in healthcare, government, etc. To the best of our knowledge, there has not been a controlled user evaluation to measure the impact of non-uniform information access on CIR outcomes. To address this shortcoming, we conducted a controlled user evaluation using 2 non-uniform access scenarios (document removal and term blacklisting) and 1 full and uniform access scenario. Following this, a design interview was undertaken to provide interface design suggestions. Evaluation results show that neither of the 2 non-uniform access scenarios had a significant negative impact on collaborative and individual search outcomes. Design interview results suggested that awareness of team's query history and intersecting viewed/judged documents could potentially help users share their expertise without disclosing sensitive information. Based on our results we provide important design recommendations to better support users with non-uniform information access in CIR.

The majority of research into Collaborative Information Retrieval (CIR) has assumed a uniformity of information access and visibility between collaborators. However in a number of real world scenarios, information access is not uniform between all collaborators in a team e.g. security, health etc. This can be referred to as Multi-Level Collaborative Information Retrieval (MLCIR). To the best of our knowledge, there has not yet been any systematic investigation of the effect of MLCIR on search outcomes. To address this shortcoming, in this paper, we present the results of a simulated evaluation conducted over 4 different non-uniform information access scenarios and 3 different collaborative search strategies. Results indicate that there is some tolerance to removing access to the collection and that there may not always be a negative impact on performance. We also highlight how different access scenarios and search strategies impact on search outcomes.