Methods and apparatus to determine audience viewing of video-on-demand programs

A tangible article of manufacture storing machine readable instructions that, when executed, cause a machine to at least:

• obtain server metering data determined using a server metering device in communication with a video-on-demand (VOD) server, the VOD server to provide VOD content specifically to a first subscriber site among a plurality of subscriber sites, the VOD content comprising a plurality of VOD content streams, the server metering data including session information describing a VOD session established with the first subscriber site to provide the VOD content and different stream information describing different VOD content streams provided to the first subscriber site during the VOD session;
• obtain subscriber metering data corresponding to media content presented at the first subscriber site, the subscriber metering data determined using a site metering device different from the server metering device;
• and
• combine the subscriber metering data and the server metering data to monitor the VOD content provided specifically to the first subscriber site, the subscriber metering data indicating whether VOD content was selected for presentation at the first subscriber site and including a first identifier to uniquely identify the first subscriber site, the server metering data determined independently of the subscriber metering data and including a second identifier to identify the first subscriber site and to identify a first portion of the server metering data associated with the first subscriber site, the first portion of the server metering data to be combined with the subscriber metering data based on the first identifier.

A system to monitor presentation of video-on-demand (VOD) content, the system comprising:

• a server metering device in communication with a VOD server to determine server metering data corresponding to the VOD server, the VOD server to provide the VOD content specifically to a first subscriber site among a plurality of subscriber sites;
• a site metering device to determine subscriber metering data corresponding to media content presented at the first subscriber site, the server metering device different from the site metering device;
• and
• a facility to replace a portion of the subscriber metering data with a portion of the server metering data to combine the subscriber metering data and the server metering data to monitor the VOD content provided specifically to the first subscriber site, the subscriber metering data including a site metering device identifier to uniquely identify the first subscriber site, the portion of the subscriber metering data determined independently of the subscriber metering data and indicating that VOD content was selected for presentation at the first subscriber site, the portion of the server metering data including a set-top box identifier to identify the first subscriber site and to indicate that the portion of the server metering data is associated with the first subscriber site, the site metering device identifier being different from the set-top box identifier, the portion of the server metering data to be selected for replacing the portion of the subscriber metering data based on the set-top box identifier and the site metering device identifier.