Embed Size (px)
Citation preview
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Evaluating the Effectiveness of Automatic PVR ManagementKetan Mayer-PatelWesley Miaw
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Personal Video Recorders• Time-shifted viewing• Show archiving• Hundreds of hours worth of storage• “TV Guide” integration• Recommendations
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
PVR Recommendation
• Pros:♦ Total awareness♦ Learned viewing preferences
• Cons:♦ Inaccurate
PVR: Total awareness + Errorvs.
Human: Limited awareness + No error
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Simulation
• 180 days• PVR capacity: 100 half-hour
shows• Each half hour, save show of
highest utility.• Delete programs of lowest utility
as necessary.• End of day, compute total utility
and delete consumed shows.• First week ignored.
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
PVR Model
• Number of Channels• Viewer Consumption Rate• Content Utility Distribution
[0,1]• Utility Decay Rate• Selection Policy (Automatic or
Manual)
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
The Tradeoff
• 200 channels• 8 half-hour shows
viewed each day
• CUD gaussian z=10• 0.975 decay factor
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Channels
• X channels• 8 half-hour shows
viewed each day
• CUD gaussian z=10• 0.975 decay factor
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Consumption Rate
• 200 channels• X half-hour shows
viewed each day
• CUD gaussian z=10• 0.975 decay factor
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Content Utility Distribution
• 200 channels• 8 half-hour shows
viewed each day
• CUD gaussian z=X• 0.975 decay factor
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Decay Rate
• 200 channels• 8 half-hour shows
viewed each day
• CUD gaussian z=10• X decay factor
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Conclusion
• Margin of error has very little effect on automatic policy performance.
• Even if the automatic policy has very small error, a human with sufficiently high awareness will beat it.
• The automatic policy is useful to very unaware or very picky people.
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Looking Ahead
• Available content is overwhelming♦ Hundreds of channels♦ Thousands of program hours each day
• Broadcast is necessary♦ Video requires ~1GB/hour
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Recommendation Silliness• “I recorded an episode of Oprah…it
started recording all kinds of BET and hip-hop shows.” – Rapunzel
• “I taped a few Spanish-language soccer games…a year later stuff in Spanish is constantly being suggested to me.” – Matt
http://www.pvrblog.com/pvr/2003/07/pvrs_and_the_ga.html
The UNIVERSITY of NORTH CAROLINA at CHAPEL HILL
Resources
• http://www.wesman.net/~wesley/presentations/pvr.ppt
• http://www.wesman.net/~wesley/papers/pvr.pdf
