5.1.1 Introduction

  • Scope: Hundreds of millions of people upload billions of videos.

  • Core Goal of SNA on YouTube: To visualize connected landscapes of videos and users to highlight patterns of producers, commentators, and consumers.

  • Significance: Online video sharing has shifted from a solitary, technical task to a mainstream social practice. Popularity is not uniform; different types of content generate different network structures.


5.1.2 What Is YouTube?

  • History: Created in 2005; acquired by Google in 2006.

  • Statistics (as of Oct 2009):

    • Over 1 billion videos watched daily.

    • Between 21% and 23% of all internet users visit YouTube monthly.

    • 24 hours of video uploaded every minute.

  • Success Factors:

    1. Ease of Use: Simple uploading and instant playback (no proprietary player installations).

    2. Strategic Collaborations: Partners with studios, networks, and political parties.

    3. Social Integration: Code embedding allows videos to be shared across blogs, wikis, and social media, driving “viral” growth via electronic word-of-mouth.


5.1.3 YouTube’s Structure

YouTube maintains a clear distinction between Videos (Content) and Users (Community), though they are closely linked.

5.1.3.1 Videos

Every video has a standardized page containing:

  • Metadata: Title, author, description, tags, and category.

  • Statistics: View counts, ratings, and geographical popularity maps.

  • Interaction Tools:

    • Textual Comments: Can be threaded or flagged as spam.

    • Video Responses: A video directly linked to the original.

    • Ratings: Like/Dislike buttons.

  • Related Videos: Generated by YouTube’s algorithm based on commonalities and user paths.

5.1.3.2 Users’ Channels

User profiles (“channels”) act as hubs for:

  • Personal Info: Name, age, location, and social media links.

  • Explicit Networks:

    1. Subscribers: Directed, asymmetric ties (following a channel).

    2. Friends: Bilateral, symmetric ties (requires mutual approval).

  • Widgets: Customizable boxes for activity logs, playlists, and “favorited” videos.


5.1.4 Networks in YouTube

5.1.4.1 Video Networks

  • Shared Descriptors: Edges connect videos sharing the same tags or categories.

  • Video Responses: Direct links between a response video and the source.

  • Comment Networks: Edges connect videos commented on by the same user.

5.1.4.2 Users’ Networks

  • Explicit: Subscription and friendship lists.

  • Implicit: Created via interactions like commenting on a channel profile, rating, or favoriting.


5.1.5 Key Analytical Questions

  • Centrality: Which videos/users lead a category? Who are the “rising stars”?

  • Groups: Do videos form dense hubs based on niche interests (e.g., Japanese anime, makeup)?

  • Temporal: How does a viral video disrupt or reinforce existing networks?

  • Structural: What are the differences between a user’s subscription network (fans) and friendship network (peers)?


5.1.6 Importing YouTube Data into NodeXL

5.1.6.1 Video Data

  • Import Method: Search by keywords (e.g., “makeup”).

  • Edge Types: Tags, shared commenters, or video responses.

  • Limitation: Searches titles/metadata, but not the actual audio/video content.

5.1.6.2 User Data

  • Import Method: Search by exact channel name.

  • Levels:

    • 1.0: Direct neighbors.

    • 1.5: Direct neighbors and the ties between them.

    • 2.0: Includes friends-of-friends.

5.1.6.3 - 5.1.6.4 Technical & Ethical Issues

  • Privacy: If a user marks lists as private, NodeXL cannot retrieve them.

  • API Reliability: Web requests may time out, leading to inconsistent data.

  • Ethics: Researchers must handle personally identifiable info (faces + names + opinions) with care to avoid embarrassment or disclosure of sensitive data.


5.1.8 Case Studies: Analyzing YouTube Networks

5.1.8.1 User Networks: Celebrity vs. Community

The text compares two different types of prominence:

  1. Rihanna (Celebrity): * Structure: A “star” network.

    • Metrics: Extremely sparse (Density: 0.008).

    • Behavior: The channel is a promotional showcase; fans connect to Rihanna but not to each other.

  2. Leesha Harvey (Folk Singer):

    • Structure: A cohesive community.

    • Metrics: High density (0.166).

    • Behavior: Features multiple hubs of mutual friends and folk-genre enthusiasts who support one another.

5.1.8.3 The “Makeup” Video Network

  • Finding: shared-tag networks are very dense. Filtering by Edge Weight (frequency of shared tags) is necessary to see patterns.

  • Boundary Objects: The “Natural makeup” video had the highest Betweenness Centrality. It acted as a “bridge” between everyday makeup users and theatrical/alternative makeup communities.

  • Note: The most central videos (pivotal to the community) were not necessarily the most popular (most viewed) in the global YouTube population.

5.1.8.4 Healthcare Reform Networks

  • Controversy vs. Popularity: High comment counts did not correlate with high ratings. Controversial videos sparked “heated discussions” but received lower ratings from dissenters.

  • Central Players: Satirical news (e.g., The Young Turks) and snippets of politicians (e.g., Mike Rogers) generated more prolonged and lively discussion than informational or personal vlogs.


5.1.9 - 5.1.10 Summary & Agenda

  • Practitioners: SNA helps gauge public trends and decide which “creative routes” maximize outcome while avoiding backlash.

  • Researchers: YouTube research is in early stages compared to Twitter/Facebook. The key is the interplay between content and structure—how the web of social ties determines what becomes popular.


Exam Tip: Be prepared to define Boundary Objects and explain why Rihanna’s network is a “star” structure (low density) while a niche community like folk music has high density.