Nielsen Twitter TV Ratings - Weekly Top Ten 18th Nov - 24th Nov 2013 - best f y

Nielsen Twitter TV Ratings Weekly Top Ten list is ranked by Unique Audience and include four metrics for each of the top episodes.

Tweets - Tweets ascribed to a linear TV episode.
Unique Authors – Unique Twitter accounts that have sent at least one Tweet ascribed to a specific TV episode.
Impressions - The number of times any Tweets ascribed to a TV episode were seen.
Unique Audience – The total number of distinct Twitter accounts accruing at least one impression of one or more different Tweets ascribed to a TV episode.