A Hybrid Approach to Music Playlist Continuation Based on Playlist-Song Membership

Automated music playlist continuation is a common task of music recommender systems, that generally consists in providing a fitting extension to a given playlist. Collaborative filtering models, that extract abstract patterns from curated music playlists, tend to provide better playlist continuations than content-based approaches. However, pure collaborative filtering models have at least one of the following limitations: (1) they can only extend playlists profiled at training time; (2) they misrepresent songs that occur in very few playlists. We introduce a novel hybrid playlist continuation model based on what we name "playlist-song membership", that is, whether a given playlist and a given song fit together. The proposed model regards any playlist-song pair exclusively in terms of feature vectors. In light of this information, and after having been trained on a collection of labeled playlist-song pairs, the proposed model decides whether a playlist-song pair fits together or not. Experimental results on two datasets of curated music playlists show that the proposed playlist continuation model compares to a state-of-the-art collaborative filtering model in the ideal situation of extending playlists profiled at training time and where songs occurred frequently in training playlists. In contrast to the collaborative filtering model, and as a result of its general understanding of the playlist-song pairs in terms of feature vectors, the proposed model is additionally able to (1) extend non-profiled playlists and (2) recommend songs that occurred seldom or never in training~playlists

Parsing consumption preferences of music streaming audiences

As demands for insights on music streaming listeners continue to grow, scientists and industry analysts face the challenge to comprehend a mutated consumption behavior, which demands a renewed approach to listener typologies. This study aims to determine how audience segmentation can be performed in a time-relevant and replicable manner. Thus, it interrogates which parameters best serve as indicators of preferences to ultimately assist in delimiting listener segments. Accordingly, the primary objective of this research is to develop a revised typology that classifies music streaming listeners in the light of the progressive phenomenology of music listening. The hypothesis assumes that this could be solved by positioning listeners – rather than products – at the center of streaming analysis and supplementing sales- with user-centered metrics. The empirical research of this paper was based on grounded theories, enriched by analytical case studies. For this purpose, behavioral and psychological research results were interconnected with market analysis and streaming platform usage data. Analysis of the results demonstrates that a concatenation of multi-dimensional data streams facilitates the derivation of a typology that is applicable to varying audience pools. The findings indicate that for the delimitation of listener types, the motivation, and listening context are essential key constituents. Since these variables demand insights that reach beyond existing metrics, descriptive data points relating to the listening process are subjoined. Ultimately, parameter indexation results in listener profiles that offer novel access points for investigations, which make imperceptible, interdisciplinary correlations tangible. The framework of the typology can be consulted in analytical and creational processes. In this respect, the results of the derived analytical approach contribute to better determine and ultimately satisfy listener preferences.Während die Nachfrage nach Erkenntnissen über Musik-Streaming-Hörer kontinuierlich steigt, stehen Wissenschaftler sowie Industrieanalysten einem geänderten Konsumptions- verhalten gegenüber, das eine überarbeitete Hörertypologie fordert. Die vorliegende Studie erörtert, wie eine Hörersegmentierung auf zeitgemäße und replizierbare Weise umgesetzt werden kann. Demnach beschäftigt sie sich mit der Frage, welche Parameter am besten als Indikatoren für Hörerpräferenzen dienen und wie diese zur Abgrenzung der Publikumsseg- mente beitragen können. Dementsprechend ist es das primäre Ziel dieser Forschung, eine überarbeitete Typologie aufzustellen, die Musik-Streaming-Hörer in Anbetracht der progressiven Erscheinungsform des Musikhörens klassifiziert. Die Hypothese nimmt an, dass dies realisierbar ist, wenn der Hörer – anstelle von Produkten – im Zentrum der Streaming-Analyse steht und absatzzen- trierte durch hörerzentrierte Messungen ergänzt werden. Die empirische Forschung basiert auf systematischen Theorien, untermauert durch analytische Fallbeispiele. Hierfür werden psychologische und verhaltenswissenschaftliche Forschungserkenntnisse mit Marktanalysen und Nutzerdaten von Musikstreaming-Portalen fusioniert. Die Analyse der Ergebnisse verdeutlicht, dass eine Verkettung von multidimensionalen Rohdaten die Erhebung einer Typologie ermöglicht, die auf mehrere Hörergruppen anwend- bar ist. Die Befunde signalisieren, dass die Hörmotivation und der Hörkontext bei der Abgrenzung der Publikumstypen Schlüsselelemente darstellen. Da diese Variablen spezifis- che Kenntnisse fordern, die über vorliegende Kennzahlen hinausgehen, werden deskriptive Datenpunkte über den Hörvorgang ergänzt. Letztlich, resultiert die Indexierung der Pa- rameter in Hörerprofilen, die neue Zugangspunkte für Untersuchungen bieten, die nicht ersichtliche, interdisziplinäre Korrelationen greifbar machen. Das Gerüst der Hörertypologie kann sowohl in Erstellungs- als auch in Analyseprozessen herangezogen werden. Somit tragen die Ergebnisse der entwickelten Analysemethode zum Verständnis und letztlich zur Erfüllung von Hörerpräferenzen bei

Parsing consumption preferences of music streaming audiences

As demands for insights on music streaming listeners continue to grow, scientists and industry analysts face the challenge to comprehend a mutated consumption behavior, which demands a renewed approach to listener typologies. This study aims to determine how audience segmentation can be performed in a time-relevant and replicable manner. Thus, it interrogates which parameters best serve as indicators of preferences to ultimately assist in delimiting listener segments. Accordingly, the primary objective of this research is to develop a revised typology that classifies music streaming listeners in the light of the progressive phenomenology of music listening. The hypothesis assumes that this could be solved by positioning listeners – rather than products – at the center of streaming analysis and supplementing sales- with user-centered metrics. The empirical research of this paper was based on grounded theories, enriched by analytical case studies. For this purpose, behavioral and psychological research results were interconnected with market analysis and streaming platform usage data. Analysis of the results demonstrates that a concatenation of multi-dimensional data streams facilitates the derivation of a typology that is applicable to varying audience pools. The findings indicate that for the delimitation of listener types, the motivation, and listening context are essential key constituents. Since these variables demand insights that reach beyond existing metrics, descriptive data points relating to the listening process are subjoined. Ultimately, parameter indexation results in listener profiles that offer novel access points for investigations, which make imperceptible, interdisciplinary correlations tangible. The framework of the typology can be consulted in analytical and creational processes. In this respect, the results of the derived analytical approach contribute to better determine and ultimately satisfy listener preferences.Während die Nachfrage nach Erkenntnissen über Musik-Streaming-Hörer kontinuierlich steigt, stehen Wissenschaftler sowie Industrieanalysten einem geänderten Konsumptions- verhalten gegenüber, das eine überarbeitete Hörertypologie fordert. Die vorliegende Studie erörtert, wie eine Hörersegmentierung auf zeitgemäße und replizierbare Weise umgesetzt werden kann. Demnach beschäftigt sie sich mit der Frage, welche Parameter am besten als Indikatoren für Hörerpräferenzen dienen und wie diese zur Abgrenzung der Publikumsseg- mente beitragen können. Dementsprechend ist es das primäre Ziel dieser Forschung, eine überarbeitete Typologie aufzustellen, die Musik-Streaming-Hörer in Anbetracht der progressiven Erscheinungsform des Musikhörens klassifiziert. Die Hypothese nimmt an, dass dies realisierbar ist, wenn der Hörer – anstelle von Produkten – im Zentrum der Streaming-Analyse steht und absatzzen- trierte durch hörerzentrierte Messungen ergänzt werden. Die empirische Forschung basiert auf systematischen Theorien, untermauert durch analytische Fallbeispiele. Hierfür werden psychologische und verhaltenswissenschaftliche Forschungserkenntnisse mit Marktanalysen und Nutzerdaten von Musikstreaming-Portalen fusioniert. Die Analyse der Ergebnisse verdeutlicht, dass eine Verkettung von multidimensionalen Rohdaten die Erhebung einer Typologie ermöglicht, die auf mehrere Hörergruppen anwend- bar ist. Die Befunde signalisieren, dass die Hörmotivation und der Hörkontext bei der Abgrenzung der Publikumstypen Schlüsselelemente darstellen. Da diese Variablen spezifis- che Kenntnisse fordern, die über vorliegende Kennzahlen hinausgehen, werden deskriptive Datenpunkte über den Hörvorgang ergänzt. Letztlich, resultiert die Indexierung der Pa- rameter in Hörerprofilen, die neue Zugangspunkte für Untersuchungen bieten, die nicht ersichtliche, interdisziplinäre Korrelationen greifbar machen. Das Gerüst der Hörertypologie kann sowohl in Erstellungs- als auch in Analyseprozessen herangezogen werden. Somit tragen die Ergebnisse der entwickelten Analysemethode zum Verständnis und letztlich zur Erfüllung von Hörerpräferenzen bei

Explainability in Music Recommender Systems

The most common way to listen to recorded music nowadays is via streaming platforms which provide access to tens of millions of tracks. To assist users in effectively browsing these large catalogs, the integration of Music Recommender Systems (MRSs) has become essential. Current real-world MRSs are often quite complex and optimized for recommendation accuracy. They combine several building blocks based on collaborative filtering and content-based recommendation. This complexity can hinder the ability to explain recommendations to end users, which is particularly important for recommendations perceived as unexpected or inappropriate. While pure recommendation performance often correlates with user satisfaction, explainability has a positive impact on other factors such as trust and forgiveness, which are ultimately essential to maintain user loyalty. In this article, we discuss how explainability can be addressed in the context of MRSs. We provide perspectives on how explainability could improve music recommendation algorithms and enhance user experience. First, we review common dimensions and goals of recommenders' explainability and in general of eXplainable Artificial Intelligence (XAI), and elaborate on the extent to which these apply -- or need to be adapted -- to the specific characteristics of music consumption and recommendation. Then, we show how explainability components can be integrated within a MRS and in what form explanations can be provided. Since the evaluation of explanation quality is decoupled from pure accuracy-based evaluation criteria, we also discuss requirements and strategies for evaluating explanations of music recommendations. Finally, we describe the current challenges for introducing explainability within a large-scale industrial music recommender system and provide research perspectives.Comment: To appear in AI Magazine, Special Topic on Recommender Systems 202

Tune in to your emotions: a robust personalized affective music player

The emotional power of music is exploited in a personalized affective music player (AMP) that selects music for mood enhancement. A biosignal approach is used to measure listeners’ personal emotional reactions to their own music as input for affective user models. Regression and kernel density estimation are applied to model the physiological changes the music elicits. Using these models, personalized music selections based on an affective goal state can be made. The AMP was validated in real-world trials over the course of several weeks. Results show that our models can cope with noisy situations and handle large inter-individual differences in the music domain. The AMP augments music listening where its techniques enable automated affect guidance. Our approach provides valuable insights for affective computing and user modeling, for which the AMP is a suitable carrier application

Social software for music

Tese de mestrado integrado. Engenharia Informática e Computação. Faculdade de Engenharia. Universidade do Porto. 200

Investigating bias in Music Recommender Systems

Music Recommender Systems (MRS) are software applications that provide personalized music recommendations based on user preferences and listening history. They analyze data to suggest music that aligns with individual tastes, enhancing the music discovery experience. This thesis aims to investigate the influence of record labels across different music recommendation datasets and evaluate their impact on recommender systems. Additionally, it seeks to expand the scope and experimentation of prior research on bias within feedback loops of MRS. To study their effect, the datasets are preprocessed and fed into a multi-stage web crawler that retrieves record label information for individual albums as well as an assignment to a major record company (Universal, Sony, Warner) or independent. This crawler is used to enrich our dataset collection. Based on the additional information, we can show different characteristics and identify particular biases in their user-generated music collections of playlists and listening profiles. Moreover, recommender system experiments are conducted, presenting results of feedback loop simulations, where the stability of record label distribution in longitudinal recommendations are studied. All findings and gathered record label information are made publicly available to the research community.Els Sistemes de Recomanació Musical (MRS) són aplicacions de software que proporcionen recomanacions de música personalitzades basades en les preferències i el històric d'escolta de l'usuari. Analitzen dades per suggerir música que s'ajusti als gustos individuals, millorant així l'experiència de descobriment musical. Aquesta tesi té com a objectiu investigar la influència de les discogràfiques en diferents conjunts de dades de recomanació musical i avaluar el seu impacte en els sistemes de recomanació. A més, busca ampliar l'abast i l'experimentació de recerques prèvies sobre biaixos en els bucles de retroalimentació dels MRS. Per estudiar el seu efecte, els conjunts de dades es pre-processen i s'insereixen a un rastrejador web de diverses etapes que recopila informació sobre les discogràfiques dels àlbums individuals, així com la seva classificació en una discogràfica principal (Universal, Sony, Warner) o independent. Aquest rastrejador s'utilitza per enriquir la nostra col·lecció de dades. Basant-nos en la informació addicional, podem mostrar diferents característiques i identificar biaixos particulars en les col·leccions de música generades pels usuaris, com ara llistes de reproducció i perfils d'escolta. A més, es fan experiments en un entorn simulat de recomanacions, presentant els primers resultats de la simulació de bucles de retroalimentació on s'estudia l'estabilitat de la distribució de segells discogràfics en recomanacions longitudinals. Totes les troballes i la informació recopilada de segells discogràfics es posa a la disposició del públic per a la comunitat investigadora

Sequential decision making in artificial musical intelligence

Over the past 60 years, artificial intelligence has grown from a largely academic field of research to a ubiquitous array of tools and approaches used in everyday technology. Despite its many recent successes and growing prevalence, certain meaningful facets of computational intelligence have not been as thoroughly explored. Such additional facets cover a wide array of complex mental tasks which humans carry out easily, yet are difficult for computers to mimic. A prime example of a domain in which human intelligence thrives, but machine understanding is still fairly limited, is music. Over the last decade, many researchers have applied computational tools to carry out tasks such as genre identification, music summarization, music database querying, and melodic segmentation. While these are all useful algorithmic solutions, we are still a long way from constructing complete music agents, able to mimic (at least partially) the complexity with which humans approach music. One key aspect which hasn't been sufficiently studied is that of sequential decision making in musical intelligence. This thesis strives to answer the following question: Can a sequential decision making perspective guide us in the creation of better music agents, and social agents in general? And if so, how? More specifically, this thesis focuses on two aspects of musical intelligence: music recommendation and human-agent (and more generally agent-agent) interaction in the context of music. The key contributions of this thesis are the design of better music playlist recommendation algorithms; the design of algorithms for tracking user preferences over time; new approaches for modeling people's behavior in situations that involve music; and the design of agents capable of meaningful interaction with humans and other agents in a setting where music plays a roll (either directly or indirectly). Though motivated primarily by music-related tasks, and focusing largely on people's musical preferences, this thesis also establishes that insights from music-specific case studies can also be applicable in other concrete social domains, such as different types of content recommendation. Showing the generality of insights from musical data in other contexts serves as evidence for the utility of music domains as testbeds for the development of general artificial intelligence techniques. Ultimately, this thesis demonstrates the overall usefulness of taking a sequential decision making approach in settings previously unexplored from this perspectiveComputer Science

Recommending Structured Objects: Paths and Sets

Recommender systems have been widely adopted in industry to help people find the most appropriate items to purchase or consume from the increasingly large collection of available resources (e.g., books, songs and movies). Conventional recommendation techniques follow the approach of ``ranking all possible options and pick the top'', which can work effectively for single item recommendation but fall short when the item in question has internal structures. For example, a travel trajectory with a sequence of points-of-interest or a music playlist with a set of songs. Such structured objects pose critical challenges to recommender systems due to the intractability of ranking all possible candidates. This thesis study the problem of recommending structured objects, in particular, the recommendation of path (a sequence of unique elements) and set (a collection of distinct elements). We study the problem of recommending travel trajectories in a city, which is a typical instance of path recommendation. We propose methods that combine learning to rank and route planning techniques for efficient trajectory recommendation. Another contribution of this thesis is to develop the structured recommendation approach for path recommendation by substantially modifying the loss function, the learning and inference procedures of structured support vector machines. A novel application of path decoding techniques helps us achieve efficient learning and recommendation. Additionally, we investigate the problem of recommending a set of songs to form a playlist as an example of the set recommendation problem. We propose to jointly learn user representations by employing the multi-task learning paradigm, and a key result of equivalence between bipartite ranking and binary classification enables efficient learning of our set recommendation method. Extensive evaluations on real world datasets demonstrate the effectiveness of our proposed approaches for path and set recommendation

Matchmakers or tastemakers? Platformization of cultural intermediation & social media’s engines for ‘making up taste’

There are long-standing practices and processes that have traditionally mediated between the processes of production and consumption of cultural content. The prominent instances of these are: curating content by identifying and selecting cultural content in order to promote to a particular set of audiences; measuring audience behaviours to construct knowledge about their tastes; and guiding audiences through recommendations from cultural experts. These cultural intermediation processes are currently being transformed, and social media platforms play important roles in this transformation. However, their role is often attributed to the work of users and/or recommendation algorithms. Thus, the processes through which data about users’ taste are aggregated and made ready for algorithmic processing are largely neglected. This study takes this problematic as an important gap in our understanding of social media platforms’ role in the transformation of cultural intermediation. To address this gap, the notion of platformization is used as a theoretical lens to examine the role of users and algorithms as part of social media’s distinct data-based sociotechnical configuration, which is built on the so-called ‘platform-logic’. Based on a set of conceptual ideas and the findings derived through a single case study on a music discovery platform, this thesis developed a framework to explain ‘platformization of cultural intermediation’. This framework outlines how curation, guidance, and measurement processes are ‘plat-formed’ in the course of development and optimisation of a social media platform. This is the main contribution of the thesis. The study also contributes to the literature by developing the concept of social media’s engines for ‘making up taste’. This concept illuminates how social media operate as sociotechnical cultural intermediaries and participates in tastemaking in ways that acquire legitimacy from the long-standing trust in the objectivity of classification, quantification, and measurement processes