Evaluating the Effectiveness of Automatic PVR Management

1
Evaluating the Effectiveness of Automatic PVR
Management

• Ketan Mayer-Patel
• Wesley Miaw

2
Personal Video Recorders

• Time-shifted viewing
• Show archiving
• Hundreds of hours worth of storage
• TV Guide integration
• Recommendations

3
PVR Recommendation

• Pros
• Total awareness
• Learned viewing preferences
• Cons
• Inaccurate
• PVR Total awareness Error
• vs.
• Human Limited awareness No error

4
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.

5
PVR Model

• Number of Channels
• Viewer Consumption Rate
• Content Utility Distribution 0,1
• Utility Decay Rate
• Selection Policy (Automatic or Manual)

6
The Tradeoff

• 200 channels
• 8 half-hour shows viewed each day

• CUD gaussian z10
• 0.975 decay factor

7
Channels

• X channels
• 8 half-hour shows viewed each day

• CUD gaussian z10
• 0.975 decay factor

8
Consumption Rate

• 200 channels
• X half-hour shows viewed each day

• CUD gaussian z10
• 0.975 decay factor

9
Content Utility Distribution

• 200 channels
• 8 half-hour shows viewed each day

• CUD gaussian zX
• 0.975 decay factor

10
Decay Rate

• 200 channels
• 8 half-hour shows viewed each day

• CUD gaussian z10
• X decay factor

11
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.

12
Looking Ahead

• Available content is overwhelming
• Hundreds of channels
• Thousands of program hours each day
• Broadcast is necessary
• Video requires 1GB/hour

13
Recommendation Silliness

• I recorded an episode of Oprahit started
  recording all kinds of BET and hip-hop shows.
  Rapunzel
• I taped a few Spanish-language soccer gamesa
  year later stuff in Spanish is constantly being
  suggested to me. Matt
• http//www.pvrblog.com/pvr/2003/07/pvrs_and_the_ga
  .html

14
Resources

• http//www.wesman.net/wesley/presentations/pvr.pp
  t
• http//www.wesman.net/wesley/papers/pvr.pdf
• wesley_at_wesman.net