Development of Music Recommendation System based on Customer Sentiment Analysis

Music is one of the most creative act that can express human sentiment with sound. Also, since music invoke people's sentiment to get empathized with it easily, it can either encourage or discourage people's sentiment with music what they are listening. Thus, sentiment is the primary factor when it comes to searching or recommending music to people. Regard to the music recommendation system, there are still lack of recommendation systems that are based on customer sentiment. An algorithm's that were used in previous music recommendation systems are mostly user based, for example, user's play history and playlists etc. Based on play history or playlists between multiple users, distance between music were calculated refer to basic information such as genre, singer, beat etc. It can filter out similar music to the users as a recommendation system. However those methodology have limitations like filter bubble. For example, if user listen to rock music only, it would be hard to get hip-hop or R&B music which have similar sentiment as a recommendation. In this study, we have focused on sentiment of music itself, and finally developed methodology of defining new index for music recommendation system. Concretely, we are proposing "SWEMS" index and using this index, we also extracted "Sentiment Pattern" for each music which was used for this research. Using this "SWEMS" index and "Sentiment Pattern", we expect that it can be used for a variety of purposes not only the music recommendation system but also as an algorithm which used for buildup predicting model etc. In this study, we had to develop the music recommendation system based on emotional adjectives which people generally feel when they listening to music. For that reason, it was necessary to collect a large amount of emotional adjectives as we can. Emotional adjectives were collected via previous study which is related to them. Also more emotional adjectives has collected via social metrics and qualitative interview. Finally, we could collect 134 individual adjectives. Through several steps, the collected adjectives were selected as the final 60 adjectives. Based on the final adjectives, music survey has taken as each item to evaluated the sentiment of a song. Surveys were taken by expert panels who like to listen to music. During the survey, all survey questions were based on emotional adjectives, no other information were collected. The music which evaluated from the previous step is divided into popular and unpopular songs, and the most relevant variables were derived from the popularity of music. The derived variables were reclassified through factor analysis and assigned a weight to the adjectives which belongs to the factor. We define the extracted factors as "SWEMS" index, which describes sentiment score of music in numeric value. In this study, we attempted to apply Case Based Reasoning method to implement an algorithm. Compare to other methodology, we used Case Based Reasoning because it shows similar problem solving method as what human do. Using "SWEMS" index of each music, an algorithm will be implemented based on the Euclidean distance to recommend a song similar to the emotion value which given by the factor for each music. Also, using "SWEMS" index, we can also draw "Sentiment Pattern" for each song. In this study, we found that the song which gives a similar emotion shows similar "Sentiment Pattern" each other. Through "Sentiment Pattern", we could also suggest a new group of music, which is different from the previous format of genre. This research would help people to quantify qualitative data. Also the algorithms can be used to quantify the content itself, which would help users to search the similar content more quickly.

소비자 감성 분석 기반의 음악 추천 알고리즘 개발

음악은 인간의 감성을 소리로 표현하는 창조적 예술 행위이다. 음악은 사람들의 기분을 우울하게 혹은 기쁘게 변화시킬 수 있다. 따라서 음악을 감상하는 데 있어 감성은 소비자에게 적합한 음악을 찾고 들려주는 데 매우 중요한 요소인데, 다양한 음원 서비스에서 제공하는 추천 알고리즘은 사용자의 기본적인 정보(성별, 나이, 감상 횟수 등)와 사용자의 플레이 기록에 기반한 음악 추천 방식을 주로 사용하고 있다. 본 연구에서는 음악을 감상하는 개인의 감성을 고려하여 각 음원이 가지는 고유의 감성을 기본으로 한 음악 추천 알고리즘을 제안해 보고자 한다. 구체적으로, 사용자들이 자주 듣는 음악과 그렇지 않은 음악을 기준으로 '감정 패턴'을 추출 후 상관관계를 확인하고자 하며, 앞선 결과를 기반으로 사용자들이 원하는 노래에 대한 검색과 사용자 감성 기반 추천 방법을 도출해내보고자 한다. 이를 위해 본 연구에서는 사례기반추론 기법을 이용하여 사람들이 주로 듣는 음악과 비슷한 '감성 패턴'을 갖는 특정한 곡을 추천해주는 알고리즘을 개발하였다. 먼저, 분석에 필요한 감정 형용사를 정리하여 변수화 시키고, 의미 있는 것끼리 묶어 음악 감성지수를 개발하였고, 분석의 대상이 될 음원에 대해 고유의 감성지수 점수를 측정하였다. 마지막으로 도출된 점수의 결과를 통해 유사한 감정 패턴이 나오는 곡들을 유사 곡 리스트로 분류하고 사용자들에게 추천하는 과정을 거친다. 앞선 일련의 과정을 거처 도출된 결과는 음원 추천 시스템뿐만 아니라, 인기 있는 곡과 아닌 곡에 영향을 미치는 변수 도출 및 음원 출시 전, 해당 곡의 스트리밍 수 예측 모형 구축 등 다양한 용도로 사용될 수 있을 것으로 기대한다.