Dominance Weighted Social Choice Functions for Group Recommendations

In travel domains, decision support systems provide support to tourists in the planning of their vacation. In particular, when the number of possible Points of Interest (POI) to visit is large, the system should help tourists providing recommendations on the POI that could be more interesting for them. Since traveling is, usually, an activity that involves small groups of people, the system should take simultaneously into account the preferences of each group's member. At the same time, it also should model possible intra-group relationships, which can have an impact in the group decision-making process. In this paper, we model this problem as a multi-agent aggregation of preferences by using weighted social choice functions, whereas such weights are automatically evaluated by analyzing the interactions of the group's members on Online Social Networks

A Co-design Study for Multi-Stakeholder Job Recommender System Explanations

Recent legislation proposals have significantly increased the demand for eXplainable Artificial Intelligence (XAI) in many businesses, especially in so-called `high-risk' domains, such as recruitment. Within recruitment, AI has become commonplace, mainly in the form of job recommender systems (JRSs), which try to match candidates to vacancies, and vice versa. However, common XAI techniques often fall short in this domain due to the different levels and types of expertise of the individuals involved, making explanations difficult to generalize. To determine the explanation preferences of the different stakeholder types - candidates, recruiters, and companies - we created and validated a semi-structured interview guide. Using grounded theory, we structurally analyzed the results of these interviews and found that different stakeholder types indeed have strongly differing explanation preferences. Candidates indicated a preference for brief, textual explanations that allow them to quickly judge potential matches. On the other hand, hiring managers preferred visual graph-based explanations that provide a more technical and comprehensive overview at a glance. Recruiters found more exhaustive textual explanations preferable, as those provided them with more talking points to convince both parties of the match. Based on these findings, we describe guidelines on how to design an explanation interface that fulfills the requirements of all three stakeholder types. Furthermore, we provide the validated interview guide, which can assist future research in determining the explanation preferences of different stakeholder types

A Framework for Group Context Aware Recommendation Systems

This Ph.D. thesis addresses the problem of Group Recommendation Systems (GRSs) with the aim to define a general framework to integrate in the process of generation of the recommendations for a specific group social aspects related to the interactions between group's members, to the type and the status of the social relationship within the group, and even aspect related to the personality of the group's members. The objective is the realization of techniques that permit to better model the real interactions characterizing the group decision-making process and obtain most suitable recommendations

Towards a Collaborative Filtering Framework for Recommendation in Museums: From Preference Elicitation to Group's Visits

AbstractRecommendation systems based on collaborative filtering methods can be exploited in the context of providing personalized artworks tours within a museum. However, in order to be effectively used, several problems have to be addressed: user preferences are not expressed as rating, items to be suggested are located in a physical space, and users may be in a group. In this work, we present a general framework that, by using the Matrix Factorization (MF) approach and a graph representation of a museum, addresses the problem of generating and then recommending an artworks sequence for a group of visitors within a museum. To reach a high-quality initial personalization, the recommendation system uses a simple, but efficient, elicitation method that is inspired by the MF approach. Moreover, the proposed approach considers the individual or the aggregated artworks' ratings to build up a solution that takes into account the physical location of the artworks

An Introduction to the Viable Systems Approach and its Contribution to Marketing

Organizations are increasingly challenged by dynamism and turbulence that determine conditions of complexity in decision making. The aim of this paper is to highlight the need for a general frame of reference for management and marketing and to justify why adopting a systems approach is adequate at both theoretical and practical level. Specifically, the purpose of this paper is to explain why a systems approach is needed to understand business and market dynamics, and why the VSA may represent a good integrator of management and marketing theories and practices. The paper begins with a brief review of systems theories that have been proposed in the general context of management and marketing. It proceeds by illustrating the fundamental principles and concepts of the VSA and its contribution to marketing. The paper closes by discussing future research avenues and suggesting implications for researchers and practitioners

Reflections on Service Systems Boundaries: A Viable Systems Perspective. The case of the London Borough of Sutton

The aim of this paper is to propose a systems interpretation of the concept of complexity and its implications for a theoretical discussion of the concept of boundary in complex service systems. The proposal highlights the interpretative contribution of a dual perspective of observation that distinguishes between a structure-based view and a systems-based view. When dealing with complexity, the phenomenon under investigation cannot be addressed through management approaches that aim to measure and control it in a vain attempt to find the best solution. Due to the inner nature of complexity, a more rewarding approach to a full understanding of problematic situations should place consolidated management models within a more general interpretation framework that suggests preliminary insights about the real nature of the investigated phenomenon. First, this paper outlines the theoretical background of the literature on service, service systems and complex service systems, providing evidence of the contribution of recent service research advances such as service science and service-dominant logic. Next, the paper focuses on the basic principles of systems thinking to introduce the Viable Systems Approach (vSa) as a general framework of reference for both the investigation and the governance of social organisations. The vSa conceptual framework is adopted for proposing some reflections from a systems perspective in the investigation of the case of the London Borough of Sutton (LBS). The focus is on interpreting the paradoxical situation of an increased fear of crime among LBS residents despite the evidence of reduction in the crime rate. Although the incidence has fallen for most types of crimes, a recent poll confirmed that crime is still rated as the most important issue for residents. Therefore, improving safety and reducing crime remain the top priorities for the Safer Sutton Partnership Service. In short, this study proposes to consider ‘‘reducing the fear of crime in a community’’ as a complex service system

An Off-line Evaluation of Users' Ranking Metrics in Group Recommendation

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Magnetic resonance-guided focused ultrasound surgery treatment of non-spinal intra-articular osteoblastoma: feasibility, safety, and outcomes in a single-center retrospective analysis

Background: Interventional radiology, thanks to its low invasiveness and possibility to reduce the average time for the patients to come back to their normal activity, is becoming more and more promising and diffused in multiple fields. Employed without needles, MRgFUS is probably the less invasive techniques among the ones belonging to the field of interventional radiology. Purpose: To evaluate safety and effectiveness of MRgFUS in the treatment of a rare and benign, though disabling, bone lesion: intra-articular osteoblastoma. Materials and methods: A retrospective study was carried out on 6 patients (mean, 21 years) treated in the last 2 years with MRgFUS for symptomatic, histologically proved intra-articular osteoblastoma. The main inclusion criterion was the presence of a good acoustic window. The procedures consisted in MR-guided ablation, using high intensity ultrasound beams focused on the target lesion. Spinal anesthesia or peripheral nerve block was used. Clinical (based on pain and functional scales) and imaging follow-up studies were performed up to 1 year after treatment. Complications were recorded. Multiple linear regression and analysis of variance were used to assess correlations. Results: All the procedures were technically successful; no complications were observed. Painful symptomatology decreased of 88% at 6 months and 98% at 12 months (p < 0.0001), and was associated to functional improvement (p = 0.002). MRI and CT controls showed disappearance of all signs of disease and bone inflammation with a marked tendency to bone healing. Conclusion: This study shows the safety and effectiveness of MRgFUS in the treatment of intra-articular osteoblastoma with a good acoustic window