近年來,最受歡迎的推薦系統莫過於基於社群網路的個人化景點推薦系統,因為這類的系統會利用使用者自願在社群網路上留下的個人資訊,及個人的生活經驗及軌跡,推薦使用者可能喜愛的旅遊景點.如此便能省去行前進行旅遊規劃的時間,然而我們發現這類的服務往往都是針對個人去做推薦,而這個狀況並不符合大多數人的旅遊情況,因為旅遊時通常會與多人一起參加,鮮少單獨前往,像是和家人一起去野餐,或是和朋友一起去看電影.再者近年來目前各大的社群網站(Facebook、Meetup、Foursquare),在記錄打卡資料的同時也紀錄一同出遊的成員已成為一種趨勢.因此,本論文提出了HMUR( Hybrid Method with Users Rating)演算法,針對一群共同出遊的使用者(團體),進行旅遊景點的推薦.這個方法透過分析團體打卡資料及成員的個人資訊,以及根據使用者的評分來調整其推薦結果.最後,實驗部分則證明了我們所提出演算法能有效地進行團體推薦.

In recent years, the most popular recommender systems are none other than the personalized tourist attraction recommender systems on social networks, which use the personal profiles willingly provided by users on the social network and then recommend tourist attractions that the users may like based on their life experiences and trajectories. With such recommender systems, users can save time used to plan their travels ahead of time. We have found that most of these services focus on the individual when making recommendations. However, most people have company when they travel and are not alone. e.g., going picnics with family and watching movies with friends. Furthermore, looking at existing social websites (i.e. Facebook、Meetup、Foursquare), it has become a trend for check-in data to also include the accompanying members. This motivates the studies on group recommendation, which aims to recommend tourist attractions for a group of users. In this paper, we propose an algorithm named HMUR (Hybrid Method with Users Rating) to analyze the group information and user ratings, and make group recommendations. We conduct an experiments and the results show that the proposed algorithm is effective in making group recommendations, and outperforms baseline methods significantly.

Chinese Abstract i
Abstract ii
Acknowledgements iii
List of Contents iv
List of Figures v
List of Tables vi
Chapter 1 Introduction 1
Chapter 2 Related work 9
2.1 Recommender systems 9
2.1.1 Collaborative filtering recommender systems 9
2.1.2 Content-based recommender systems 10
2.1.3 Knowledge-based recommender systems 11
2.2 Group recommender systems 11
2.3 POI recommender systems 12
2.4 Technics related to our work 13
Chapter 3 Problem definition 14
Chapter 4 Algorithm 22
4.1 System framework 22
4.2 Offline processing 23
4.2.1 Analysis of group profiles 23
4.2.2 Clustering based on group check-in data 26
4.2.3 Adjustment of ratings 32
4.3 Online processing 35
4.3.1 Bit Similarity Checking (BSC) 35
4.3.2 Evaluation of POI scores 37
4.3.2.1 Calculation of similarity between two groups 38
4.3.2.1.1 Calculation of social-related similarity 38
4.3.2.1.2 Calculation of social POI-related similarity 40
4.3.2.2 Calculation of the POI scores 40
Chapter 5 Performance 42
5.1 Evaluation metrics 43
5.2 Setting an appropriate number of cluster 44
5.3 Comparison between k-means and k-kedoids clustering 45
5.3.1 Comparing the average number of categories 45
5.3.2 Comparing the query comparison of proportion between two methods 46
5.4 Baseline comparisons 47
5.5 Performance of algorithm with different relationship combinations 49
5.6 Analysis of group size 51
5.7 Influence of ratings 51
Chapter 6 Conclusions and future work 53
References 54

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