Aspects of the disclosure provide for tracking and analyzing data for user engagement of a library of content. Aspects of the disclosure provide for utilizing the tracked data more accurately to generate content rankings and recommendations, thereby improving the functionality of a system configured to provide the same. The platform can improve the reliability of metrics quantifying user engagement of hosted content, through the use of an approximate reasoning system tuned for analyzing user consumption of content with a length on the order of minutes and hours, not seconds. Current online video "viewability" standards do not address the vagueness and uncertainty of hot fraud; video viewed to completion; audio on while video viewed to completion; verifying user identity; verifying viewer legal drinking age if alcohol is involved; and a time-date stamped signature from the tagged video to provide trust, transparency, and auditable accountability.