1. 1
DATA MODELING IN IPTV AND OTT RECOMMENDER SYSTEMS –
INFORMATION FLOW FROM INTERACTION TO PERSONALIZED
RECOMMENDATIONS
Dávid Zibriczky, ImpressTV
Neo4j Meetup 2016-02-18
3. 3
Who we are?
• Acquisition of IPTV, OTT and media business line of Gravity R&D (July 2014)
• Technical Centre in Budapest, sales and management from the UK
What we are doing?
• Providing personalized recommendations, data analytics, targeted advertising and audience
measurement for corporate clients
• Main domains: Video-On-Demand, Linear TV, OTT, Advertisements
About ImpressTV
4. 4
• More time spent watching media contents than ever
• Hundreds of channels, ten thousands of movies, millions of user uploaded videos
• Heterogeneous mixture of devices and items
• Massive consumption information
• Cloudization and centralization
Then and Now
7. 7
• For the consumers
› Content discovery (relevance, time, information filtering)
› Exploring new preferences (habits, engagement)
• For the business
› Improving KPIs, balancing consumption (long tail contents)
› Promotions, targeting, campaign, analytics, reporting
• For the recommender system vendors
› Data integration/modeling, insights, data science, optimization, research
› Technology challenges, deployment, maintenance
What does a Recommender System mean in TV business?
13. Friends S01E01
Friends S02E05
Consumers
Friends S01E02
News 2016-02-
18 07:00
(Mary)
(John)
(Mark)
Contents
Star Wars IV.
VOD (SD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
News
BBC HD 07:00
Items
Inception
(HD)
VOD/SVOD
Linear (EPG items)
CatchUp
14. Friends S01E01
Friends S02E05
Consumers
Friends S01E02
News 2016-02-
18 07:00
(Mary)
(John)
(Mark)
Contents
Star Wars IV.
VOD (SD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
News
BBC HD 07:00
Items
HBO SD
HBO 2 SD
BBC HD
Inception
(HD)
TV Channels
15. Friends S01E01
Friends S02E05
Consumers
Friends S01E02
News 2016-02-
18 07:00
(Mary)
(John)
(Mark)
Contents
Star Wars IV.
VOD (SD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
News
BBC HD 07:00
Items
HBO SD
HBO 2 SD
BBC HD
Friends Series
Movie
Channels
Products
Inception
(HD)
Star Wars
Package
Inception
TVOD
($11.99)
($9.99)
($2.99)
VOD/SVOD/Channel products
16. Friends S01E01
Friends S02E05
Consumers
Friends S01E02
News 2016-02-
18 07:00
(Mary)
(John)
(Mark)
Contents
Star Wars IV.
VOD (SD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
News
BBC HD 07:00
Items
HBO SD
HBO 2 SD
Friends Series
Movie
Channels
Products
Inception
(HD)
Star Wars
Package
($11.99)
($9.99)
($2.99)
Inception
TVOD
Interface
BBC HD
Devices
(remote controller,
mouse, touch pad)
17. Friends S01E01
Friends S02E05
Consumers
Friends S01E02
News 2016-02-
18 07:00
(Mary)
(John)
(Mark)
Contents
Star Wars IV.
VOD (SD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
News
BBC HD 07:00
Items
HBO SD
HBO 2 SD
Friends Series
Movie
Channels
Products
Inception
(HD)
Star Wars
Package
($11.99)
($9.99)
($2.99)
Inception
TVOD
(19:25; 1136s)
(19:00)
(16:13; 3715s)
(20:10; 1135s)
Interface
BBC HD
(21:11; 3651s; 5*)
Implicit/Explicit
feedbacks + context
18. Friends S01E01
Friends S02E05
Consumers
Friends S01E02
News 2016-02-
18 07:00
(Mary)
(John)
(Mark)
Contents
Star Wars IV.
VOD (SD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
News
BBC HD 07:00
Items
HBO SD
HBO 2 SD
Friends Series
Movie
Channels
Products
Inception
(HD)
Star Wars
Package
($11.99)
($9.99)
($2.99)
Inception
TVOD
(19:25; 1136s)
(19:00)
(21:11; 3651s; 5*)
(16:13; 3715s)
(20:10; 1135s)
Interface
TV provider related space
BBC HD
19. Friends S01E01
Friends S02E05
Consumers
Friends S01E02
News 2016-02-
18 07:00
(Mary)
(John)
(Mark)
Contents
Star Wars IV.
VOD (SD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
News
BBC HD 07:00
Items
HBO SD
HBO 2 SD
Friends Series
Movie
Channels
Products
Inception
(HD)
Star Wars
Package
($11.99)
($9.99)
($2.99)
Inception
TVOD
(19:25; 1136s)
(19:00)
(21:11; 3651s; 5*)
(16:13; 3715s)
(20:10; 1135s)
Interface
TV provider related space
TopGear S01
Friends S01
Friends S02
Collections
BBC HD
20. Friends S01E01
Friends S02E05
Consumers
Friends S01E02
News 2016-02-
18 07:00
(Mary)
(John)
(Mark)
Contents
Star Wars IV.
VOD (SD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
News
BBC HD 07:00
Items
HBO SD
HBO 2 SD
Friends Series
Movie
Channels
Products
Inception
(HD)
Star Wars
Package
($11.99)
($9.99)
($2.99)
Inception
TVOD
(19:25; 1136s)
(19:00)
(21:11; 3651s; 5*)
(16:13; 3715s)
(20:10; 1135s)
Interface
TV provider related space
TopGear S01
Friends S01
Friends S02
Collections
Movies
Series
Shows
Domains
Domain dependent contents
BBC HD
21. Friends S01E01
Friends S02E05
Consumers
Friends S01E02
News 2016-02-
18 07:00
(Mary)
(John)
(Mark)
Contents
Star Wars IV.
VOD (SD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
News
BBC HD 07:00
Items
HBO SD
HBO 2 SD
Friends Series
Movie
Channels
Products
Inception
(HD)
Star Wars
Package
($11.99)
($9.99)
($2.99)
Inception
TVOD
(19:25; 1136s)
(19:00)
(21:11; 3651s; 5*)
(16:13; 3715s)
(20:10; 1135s)
Interface
TV provider related space
TopGear S01
Friends S01
Friends S02
Collections
Movies
Series
Shows
Domains
TV
Domain dependent contents
Musics
Books
BBC HD
22. Movies
Series
Shows
Friends S01E01
Friends S02E05
Star Wars IV.
VOD (SD)
Inception
(HD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Male
Action
Inception
HBO 20:00
Domain dependent contents
Collections Contents Items Products Interface Consumers
TV
Friends S01E02
Domains
TV provider related space
News 2016-02-
18 07:00
News
News
BBC HD 07:00
Harrison
Ford
Female
Comedy
HBO SD
HBO 2 SD
HD
SD
Friends Series
Star Wars
Package
TopGear S01
Friends S01
Friends S02
Musics
(19:25; 1136s)
(19:00)
(16:13; 3715s)
($11.99)
Movie
Channels
($9.99)
(8880s; 20:00-22:28)
(Mary)
(John)
(Mark)
(20:10; 1135s)
Inception
TVOD
($2.99)
(21:11; 3651s; 5*)
BBC HD
Meta data
Books
23. Movies
Series
Shows
Friends S01E01
Friends S02E05
Star Wars IV.
VOD (SD)
Inception
(HD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Male
Action
Inception
HBO 20:00
Domain dependent contents
Collections Contents Items Products Interface Consumers
TV
Friends S01E02
Domains
TV provider related space
News 2016-02-
18 07:00
News
News
BBC HD 07:00
Harrison
Ford
Female
Comedy
HBO SD
HBO 2 SD
HD
SD
Friends Series
Star Wars
Package
TopGear S01
Friends S01
Friends S02
Musics
(19:25; 1136s)
(19:00)
(16:13; 3715s)
($11.99)
Movie
Channels
($9.99)
(8880s; 20:00-22:28)
(Mary)
(John)
(Mark)
(20:10; 1135s)
Inception
TVOD
($2.99)
(21:11; 3651s; 5*)
BBC HD
Meta data
Books
24. 24
Graph representation
Nodes
• Entities: Users, items, contents, product, collections
• Metadata: Genres, actors, category tree nodes, gender, age group
• Node properties: Auxiliary meta data (e.g. descriptions)
Edges
• Interactions: Implicit/explicit feedbacks
• Metadata containment, relations
• Edge properties: Context, direction
30. Movies
Series
Shows
Friends S01E01
Friends S02E05
Star Wars IV.
VOD (SD)
Inception
(HD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Male
Action
Inception
HBO 20:00
Domain dependent contents
Collections Contents Items Products Interface Consumers
TV
Friends S01E02
Domains
TV provider related space
News 2016-02-
18 07:00
News
News
BBC HD 07:00
Harrison
Ford
Female
Comedy
HBO SD
HBO 2 SD
HD
SD
Friends Series
Star Wars
Package
TopGear S01
Friends S01
Friends S02
Musics
(19:25; 1136s)
(19:00)
(16:13; 3715s)
($11.99)
Movie
Channels
($9.99)
(8880s; 20:00-22:28)
(Mary)
(John)
(Mark)
(20:10; 1135s)
Inception
TVOD
($2.99)
(21:11; 3651s; 5*)
BBC HD
Meta data
Books
31. Movies
Series
Shows
Friends S01E01
Friends S02E05
Star Wars IV.
VOD (SD)
Inception
(HD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Male
Action
Inception
HBO 20:00
Domain dependent contents
Collections Contents Items Products Interface Consumers
TV
Friends S01E02
Domains
TV provider related space
News 2016-02-
18 07:00
News
News
BBC HD 07:00
Harrison
Ford
Female
Comedy
HBO SD
HBO 2 SD
HD
SD
Friends Series
Star Wars
Package
TopGear S01
Friends S01
Friends S02
Musics
(19:25; 1136s)
(19:00)
(16:13; 3715s)
($11.99)
Movie
Channels
($9.99)
(8880s; 20:00-22:28)
(Mary)
(John)
(Mark)
(20:10; 1135s)
Inception
TVOD
($2.99)
(21:11; 3651s; 5*)
BBC HD
Meta data
Books
32. Star Wars IV.
VOD (SD)
Inception
(HD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
Items Products Interface Consumers
News
BBC HD 07:00
HBO SD
HBO 2 SD
Friends Series
Star Wars
Package
(19:25; 1136s)
(19:00)
(16:13; 3715s)
($11.99)
Movie
Channels
($9.99)
(8880s; 20:00-22:28)
(Mary)
(John)
(Mark)
(20:10; 1135s)
Inception
TVOD
($2.99)
(21:11; 3651s; 5*)
BBC HD
33. Star Wars IV.
VOD (SD)
Inception
(HD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Inception
HBO 20:00
Items Consumers
News
BBC HD 07:00
(8880s; 20:00-22:28)
(Mary)
(John)
(Mark)
35. 35
Collaborative Filtering / Matrix representation
The
Matrix
The
Matrix 2
The
Matrix 3
Twilight
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 1 1 ? ?
User 2 1 1 0 0
User 3 1 0 1 1
User 4 1 0 0 1
?
?
36. 36
Collaborative Filtering / Binary preference matrix
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 1 1 ? ?
User 2 1 1 0 0
User 3 1 0 1 1
User 4 1 0 0 1
37. 37
Collaborative Filtering / Implicit MF
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1
User 2 𝒓 𝑢𝑖
User 3
User 4
Q 𝒒𝑖
PT
𝒑 𝑢
𝑇
𝑹 𝑵𝒙𝑴: preference matrix
𝑷 𝑵𝒙𝑲: user feature matrix
𝑸 𝑴𝒙𝑲: item feature matrix
𝑵: #users
𝑴: #items
𝑲: #features
𝑲 ≪ 𝑴 , 𝑲 ≪ 𝑵
𝑹~𝑷 𝐓 𝑸 𝑟 𝑢𝑖 = 𝒑 𝑢
T 𝒒𝑖
38. 38
Collaborative Filtering / Implicit MF / Weighted Sum of Squared Errors
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 1 1 ? ?
User 2 1 1 0 0
User 3 1 0 1 1
User 4 1 0 0 1
C
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 c11 c12 1 1
User 2 c21 c22 1 1
User 3 c31 1 c33 c34
User 4 c41 1 1 1
𝒇 𝑷, 𝑸 = 𝑾𝑺𝑺𝑬 =
(𝒖,𝒊)
𝒄 𝒖𝒊 𝒓 𝒖𝒊 − 𝒓 𝒖𝒊
𝟐• Objective Function:
39. 39
Collaborative Filtering / Implicit MF / Alternating Least Squares
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1
User 2
User 3
User 4
Q
0.1 -0.4 0.8 0.3
0.6 0.7 -0.1 0.8
PT
-0.2 0.6
0.6 0.4
0.7 -0.2
0.5 -0.2
𝑹~𝑷 𝐓 𝑸 𝑟 𝑢𝑖 = 𝒑 𝑢
T 𝒒𝑖
Ridge Regression
• 𝑝 𝑢 = 𝑄𝐶 𝑢
𝑄T −1
𝑄𝐶 𝑢
𝑅 𝑟 𝑢
• 𝑞𝑖 = 𝑃𝐶 𝑖 𝑃T −1
𝑃𝐶 𝑖 𝑅 𝑐 𝑖
40. 40
Collaborative Filtering / Implicit MF / Alternating Least Squares
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1
User 2
User 3
User 4
Q
0.3 -0.3 0.6 0.2
0.7 0.8 0.2 0.7
PT
-0.2 0.6
0.6 0.4
0.7 -0.2
0.5 -0.2
Ridge Regression
• 𝑝 𝑢 = 𝑄𝐶 𝑢
𝑄T −1
𝑄𝐶 𝑢
𝑅 𝑟 𝑢
• 𝑞𝑖 = 𝑃𝐶 𝑖 𝑃T −1
𝑃𝐶 𝑖 𝑅 𝑐 𝑖
𝑹~𝑷 𝐓 𝑸 𝑟 𝑢𝑖 = 𝒑 𝑢
T 𝒒𝑖
41. 41
Collaborative Filtering / Implicit MF / Alternating Least Squares
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1
User 2
User 3
User 4
Q
0.3 -0.3 0.6 0.2
0.7 0.8 0.2 0.7
PT
-0.2 0.7
0.6 0.5
0.8 -0.2
0.6 -0.2
Ridge Regression
• 𝑝 𝑢 = 𝑄𝐶 𝑢
𝑄T −1
𝑄𝐶 𝑢
𝑅 𝑟 𝑢
• 𝑞𝑖 = 𝑃𝐶 𝑖 𝑃T −1
𝑃𝐶 𝑖 𝑅 𝑐 𝑖
𝑹~𝑷 𝐓 𝑸 𝑟 𝑢𝑖 = 𝒑 𝑢
T 𝒒𝑖
42. 42
Collaborative Filtering / Implicit MF / Alternating Least Squares
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 0.02 0.45
User 2
User 3
User 4
Q
0.3 -0.3 0.6 0.2
0.7 0.8 0.2 0.7
PT
-0.2 0.7
0.6 0.5
0.8 -0.2
0.6 -0.2
𝑹~𝑷 𝐓 𝑸 𝑟 𝑢𝑖 = 𝒑 𝑢
T 𝒒𝑖
44. Movies
Series
Shows
Friends S01E01
Friends S02E05
Star Wars IV.
VOD (SD)
Inception
(HD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Male
Action
Inception
HBO 20:00
Domain dependent contents
Collections Contents Items Products Interface Consumers
TV
Friends S01E02
Domains
TV provider related space
News 2016-02-
18 07:00
News
News
BBC HD 07:00
Harrison
Ford
Female
Comedy
HBO SD
HBO 2 SD
HD
SD
Friends Series
Star Wars
Package
TopGear S01
Friends S01
Friends S02
Musics
(19:25; 1136s)
(19:00)
(16:13; 3715s)
($11.99)
Movie
Channels
($9.99)
(8880s; 20:00-22:28)
(Mary)
(John)
(Mark)
(20:10; 1135s)
Inception
TVOD
($2.99)
(21:11; 3651s; 5*)
BBC HD
Meta data
Books
45. Star Wars IV.
VOD (SD)
Inception
(HD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Action
Inception
HBO 20:00
Contents Items Products Interface Consumers
News
News
BBC HD 07:00
Harrison
Ford
Comedy
HBO SD
HBO 2 SD
HD
SD
Friends Series
Star Wars
Package
(16:13; 3715s)
Movie
Channels
(8880s; 20:00-22:28)
(John)
(20:10; 1135s)
Inception
TVOD
BBC HD
46. Star Wars IV.
VOD (SD)
Inception
(HD)
Star Wars VII.
VOD (HD)
Inception
CatchUp feb 17
Inception
HBO2 22:00
Friends S01E01
SVOD
Inception
PVR 20:00
Action
Inception
HBO 20:00
Contents Items Products Consumers
News
News
BBC HD 07:00
Harrison
Ford
Comedy
HD
SD
(8880s; 20:00-22:28)
(John)
47. 47
Content-based Filtering / Cosine Similarity (1/6)
Sci-Fi RomanceAdventure
The
Matrix
The
Matrix 2
The
Matrix 3
Twilight
48. 48
Content-based Filtering / Cosine Similarity (2/6)
Sci-Fi RomanceAdventure
The
Matrix
The
Matrix 2
The
Matrix 3
Twilight
?
?
MT Sci-Fi Adventure Romance
The
Matrix
1 1 0
The
Matrix 2
1 1 0
Twilight 0 1 1
The
Matrix 3
1 1 0
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 1 ? ?
49. 49
Content-based Filtering / Cosine Similarity (3/6)
MT Sci-Fi Adventure Romance
The
Matrix
1 1 0
The
Matrix 2
1 1 0
Twilight 0 1 1
The
Matrix 3
1 1 0
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 1 ? ?
50. 50
Content-based Filtering / Cosine Similarity (4/6)
M’T Sci-Fi Adventure Romance
The
Matrix
1/6 1/8 0
The
Matrix 2
1/6 1/8 0
Twilight 0 1/8 1/2
The
Matrix 3
1/6 1/8 0
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 1 ? ?
𝑚′𝑖𝑗 =
𝑚𝑖𝑗
𝑘 𝑚𝑖𝑘 𝑘 𝑚 𝑘𝑗
51. 51
Content-based Filtering / Cosine Similarity (5/6)
M’T Sci-Fi Adventure Romance
The
Matrix
1/6 1/8 0
The
Matrix 2
1/6 1/8 0
Twilight 0 1/8 1/2
The
Matrix 3
1/6 1/8 0
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 1 ? ?
PT Sci-Fi Adventure Romance
User 2/6 2/8 0
𝑃T = 𝑅𝑀′T
52. 52
Content-based Filtering / Cosine Similarity (6/6)
M’T Sci-Fi Adventure Romance
The
Matrix
1/6 1/8 0
The
Matrix 2
1/6 1/8 0
Twilight 0 1/8 1/2
The
Matrix 3
1/6 1/8 0
R
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 1 ? ?
PT Sci-Fi Adventure Romance
User 2/6 2/8 0
𝑹
The
Matrix
The
Matrix 2
Twilight
The
Matrix 3
User 1 1 0.268 1
𝑟𝑢𝑖 =
𝑘 𝑚′𝑖𝑘 𝑝 𝑢𝑘
𝑘 𝑚′𝑖𝑘
2
𝑘 𝑝 𝑢𝑘
2
𝑃T = 𝑅𝑀′T
54. 54
• Who is the front of the TV? (watching behavior pattern recognition)
• Cold-start problem, opt-out users (metadata enrichment, hybrid filtering)
• Noise filtering, lack of explicit data (filtering and weighting method, implicit feedbacks)
• Context-dependency (device, time, mood)
• Cross-domain recommendation, content centralization
• Time-dependent recommendable set (model-based methods)
• Popularity effect (diversification)
• Upselling, subscription (Live VOD)
• Offline vs. Online KPIs
Data Science Challenges
55. 55
• Heterogeneous external data sources (data unification)
• Big data (scalable algorithms, distributed databases)
• Latency in data transfer, streaming service
• Responsivity, load, SLA (distributed systems, load balancer)
• Maintenance, service, follow-up
• Open source vs. self-development
• Distributed systems vs. single server
• Software-as-a-service vs. on-site deployment
Technology Challenges