=Paper= {{Paper |id=Vol-1441/recsys2015_poster6 |storemode=property |title= |pdfUrl=https://ceur-ws.org/Vol-1441/recsys2015_poster6.pdf |volume=Vol-1441 |dblpUrl=https://dblp.org/rec/conf/recsys/ChenCLTY15 }} ==== https://ceur-ws.org/Vol-1441/recsys2015_poster6.pdf
      Exploiting Latent Social Listening Representations for
                    Music Recommendations

       Chih-Ming Chen1,2 , Po-Chuan Chien1 , Yu-Ching Lin3 , Ming-Feng Tsai1 , Yi-Hsuan Yang2
         1                                                  2                                                 3
         Department of Computer                              Research Center for Information                  Research Center
                  Science                                       Technology Innovation                           KKBOX Inc.
       National Chengchi University                                Academia Sinica                          Taipei 11501, Taiwan
           Taipei 11605, Taiwan                                  Taipei 11564, Taiwan                       aaronlin@kkbox.com
     {99303052, mftsai}@nccu.edu.tw                        {cmchen, yang}@citi.sinica.edu.tw

ABSTRACT                                                                      methods [1, 8] fuse the idea of topic modeling with the prob-
Music listening can be regarded as a social activity, in which                abilistic matrix factorization on social networks, in order to
people can listen together and make friends with one other.                   infer useful latent topics for collaborative filtering.
Therefore, social relationships may imply multiple facets
of the users, such as their listening behaviors and tastes.                   2.    METHODOLOGY
In this light, it is considered that social relationships hold                  Figure 1 illustrates the framework of the proposed method.
abundant valuable information that can be utilized for mu-                    We transfer the listening history and friends relationship into
sic recommendation. However, utilizing the information for                    a social listening graph. Given the social listening graph,
recommendation could be difficult, because such information                   DeepWalk is used to learn the implicit representation by seek-
is usually sparse. To address this issue, we propose to learn                 ing the possible path on the graph. The idea is to maximize
the latent social listening representations by the DeepWalk                   the co-occurrence patterns in each generated path so that the
method, and then integrate the learned representations into                   potential distance is modeled. The representation, usually
Factorization Machines to construct better recommendation                     presented as a vector, can encode the context information
models. With the DeepWalk method, user social relation-                       for further processing [7]. From theoretical perspective, the
ships can be transformed from the sparse and independent                      social representation learning is a technique of combining the
and identically distributed (i.i.d.) form into a dense and non-               recent developments of language modeling and unsupervised
i.i.d. form. In addition, the latent representations can also                 representation learning. In this work, we use the technique
capture the spatial locality among users and items, therefore                 to learn the representations on a social listening graph, and
benefiting the constructed recommendation models.                             then feed the learned representations into Factorization Ma-
                                                                              chines (FM) [9]. After being processed by DeepWalk, the
Keywords                                                                      sparse social relations will become dense and in a non-i.i.d.
                                                                              form, which can be helpful for increasing the connections
Representation Learning, Factorization Machine, Recom-
                                                                              among users and items. To our best knowledge, this work is
mender System, Social Network, Graph
                                                                              the first attempt to use deepwalk for music recommendation.
                                                                                To find the possible path, we utilize random walk to uni-
1.     BACKGROUND                                                             formly sample a series of random vertex from a graph. The
                                                                              primitive graph is constructed on the sole social network.
   Underlying almost all recommendation algorithms is an                      For the specific application of music recommendation, we
attempt to model the interaction among users and items.                       propose 3 different ways to construct such a social graph:
There have been some studies working on utilizing auxiliary                        • Social graph: Build the graph only based on users’ friends,
information for improving recommendations. In [2, 5], social                         which will enable DeepWalk to detect local community.
relationships are utilized to densify the ratings of users to
                                                                                   • Listening graph: Build the graph only based on user-item
improve the similarity computation behind the Collabora-                             listening matrix, which will enable DeepWalk to identify
tive Filtering-based (CF-based) methods. For the Matrix                              the association patterns about users and items.
Factorization-based (MF-based) methods, some studies focus
                                                                                   • Social Listening graph: Build the graph based on the
on how to incorporate social relations with other attributes                         above two relations including the user-user and user-item
of users [3, 4, 10] and how to affect the regularization term [6,                    matrices, which may hopefully fuse the merits of the pre-
11]. In addition, the Collaborative Topic Regression (CTR)                           ceding two approaches.


                                                                              3.    EXPERIMENTS
                                                                                Our experiments involve two real-world music datasets –
                                                                              hetrec2011-lastfm-2k and KKBOX-50K. The first one is a
                                                                              public benchmark dataset derived Last.fm. The second one is
                                                                              collected from a music streaming company KKBOX. Table 2
                                                                              shows some statistics of the datasets.
Copyright is held by the author(s).
                                                                                We randomly hold out 80% records for each user as the
RecSys 2015 Poster Proceedings, September 16-20, 2015, Austria, Vienna.       training data. The remaining 20% records of all users are
                              I1 I2 I3 I4 I5 I6                                                                                    Y
                                                                                                                                                         I3
                                                                                                                                                                             I6
                        U1 1        1   1    -       -    -                                                                                                        I5   U2
                                                                           I1                        I2         U4                                                             U3
                        U2 -        -   1    -       1    1                                                                                   U1
                                                                                                                                                   I2
                                                                                      U1
                                                                     U1                                                                     U4
                        U3 -        -   1    1       1    1
                                                                           I2                                              I5
                                                                                                                                                   I1         I4
                        U4 -        1   1    -       -    -                                                     U2
                                                                     U2                         I3
                                                                                                                                                                                    X
                              User-Item Matrix                             I3
                                                                                                                                         (d) Latent Representations
                                                                                                                      U4
                               U1       U2   U3          U4          U3                                    U3
                                                                           I4
                         U1     -       0        0       1                                                                        User     User Feature        Item     Item Feature
                         U2     -       -        0       0                                 I2
                                                                                                           U3                      1:1           (U1 )          1:1             (I1 )
                                                                     U4
                         U3     -       -        -       1                 I5         U1                                           1:1           (U1 )          2:1             (I2 )
                                                                                                                      I3
                                                                                                                                   1:1           (U1 )          3:1             (I3 )
                         U4     -       -        -       -                                            U4                           2:1           (U2 )          3:1             (I3 )
                           Relationship Matrix                             I6                                                      2:1           (U2 )          5:1             (I5 )
                                                                                                                 I6
                                                                                                                                   …             …               …              …

                        (a) Given Matrices                       (b) Built Graphs    (c) Random Walks                                  (e) Designed Matrix for FM
             Figure 1: Exploring latent social listening representations for music recommendation.

                                                                             hetrec2011-lastfm-2k                                                                        KKBOX-50K
      Approach                               DeepWalk                  MAP      Recall@100 Recall@200                                               MAP                  Recall@100 Recall@200
      Sole User-to-Item                          7                    4.993%     29.554%       40.308%                                             5.167%                 4.498%     8.143%
      Friendship Indexes                         7                    5.204%     32.275%       39.111%                                             2.764%                 2.031%     3.971%
      Random Social Graph                       3                     4.993%     30.479%       41.089%                                             0.311%                 0.004%     0.004%
      Social Graph                              3                     5.646%     33.328%       45.153%                                             5.155%                 4.494%     8.038%
      Listening Graph                           3                     8.423%     46.285%       60.486%                                             6.094%                 5.376%     9.658%
      Social Listening Graph                    3                     8.807%     47.962%       62.113%                                             6.157%                 5.446%     9.708%

                                                                Table 1: Recommendation Performance

 Dataset          #User          #Item                         #Record          #Relations                       for building the graph, integrating the latent representation
 lastfm-2k         1,892         17,632                           92,834           12,717                        learned from the social listening graph achieves the best
 KKBOX-50K        50,000        200,000                       50,000,000           80,000                        improvement in both MAP and recall measurements.
                                                                                                                    In current work, all the connections are considered to have
                 Table 2: Data Statistics                                                                        the same weight (i.e. the binary response) and some types of
                                                                                                                 connections are omitted (i.e. the item-to-item connections).
                                                                                                                 Hence, it is possible to earn better performance by, for exam-
treated as the testing item pool. Instead of using pure                                                          ple, assigning numeric weights to the connections or adding
precision, we use recall and mean average precision (MAP)                                                        item-to-item connections. We leave these as future work.
as the performance measurements. We repeat the evaluation
process 5 times with different randomly selected training sets
and report the average performance.                                                                              5.             REFERENCES
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