Dear Colleagues,

Recommender Systems are software tools that aim at alleviating the information overload problem by generating personalized recommendations for users. They can support users by providing a shorter and more “personalized” item catalog in order to find items that are more suitable for users’ specific tastes and preferences. Today, most e-commerce and information search and retrieval systems incorporate a recommender system as an essential tool for supporting the user of the system.

Many recommendation approaches have been developed and deployed in a vast range of application domains in the last two decades. The families of algorithms are content-based recommender systems, which suggest items of interest based on the associated content features, collaborative filtering systems, which predict the user ratings based on the previous ratings, demographic recommender systems, which build recommendations by identifying similar users based on demographic information, utility-based recommender systems, which match a user’s need and a set of options available, knowledge-based recommender systems, which attempt to suggest items that are inferred by a reasoning process and form a relationship between a user’s need and possible recommendations, and hybrid recommender systems, which aggregate a number of approaches in order to tackle the specific limitations of an individual approach.

In recent years, however, algorithms that go beyond the matrix completion paradigm have arisen. Examples are (i) algorithms that address specific scenarios, such as sequential recommendations, conversational recommendations, and recommendations in social networks, (ii) user-centric algorithms that take into account explanations, cognitive models, biases, trust, or transparency, (iii) algorithms that take into consideration multiple perspectives, such as multi-stakeholder approaches, cross-domain recommendations, and multisignal recommendations, (iv) and totally novel algorithmic approaches, such as the usage of deep learning.

This Special Issue on “Algorithms for Personalization Techniques and Recommender Systems” aims to form a reference point in this research area, i.e., the models and algorithms for the (more generic) goal of “personalization” and the (more specific) goal of “recommendations”. We invite works that present their latest findings in the state-of-the-art of the related theory and practice, and to contribute to the advancement of this research area. In particular, we would welcome original and unpublished submissions related to the following topics:

• Content-based filtering;
• Trust and transparency;
• Large scale recommendation;
• Multi-stakeholder approaches;
• Multisignal recommendations;
• Cross-domain recommendations;
• Sequential recommender systems;
• Collaborative filtering techniques;
• Side-information for recommendation;
• Adaptive recommendation algorithms;
• Visually-aware recommender systems;
• Conversational recommender systems;
• Algorithms for group recommendation;
• Semantic-aware recommender systems;
• Novel similarity-based recommendation;
• Recommendation based on deep learning;
• Recommender systems in social networks;
• Active learning for recommender systems;
• Transfer learning in recommender systems;
• Cross-domain algorithms for recommendation;
• Exploiting user cognition for recommendation;
• Recommendation based on matrix factorization;
• Recommendation based on audiovisual signals;
• Explanations methods for recommender systems;
• Generic recommendation models and algorithms;
• Algorithms for using implicit and explicit preferences;
• Ranking algorithms for personalization and adaptation;
• Novelty, diversity, or serendipity in recommender systems;
• Algorithms for context-aware recommender systems (CARS);
• Scalability and performance measures in recommender systems;
• Novel applications areas for recommender systems (e.g., health, education, and fashion);
• Further relevant topics.

Dr. Mehdi Elahi
Dr. Marko Tkalcic
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Algorithms is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• recommender systems
• collaborative filtering
• content-based filtering
• rating prediction
• ranking prediction
• active learning
• cold start