http://globalvoicesonline.org/2015/04/02/analyzing-kremlin-twitter-bots/
All four groups were merged into a single data set, resulting in a total of 17,590 Twitter accounts. As with those producing the anti-Nemtsov tweets, the metadata confirmed that the vast majority were indeed bots. 93% showed no location on their profile, 96% had no time zone information and 97% had no Twitter favorites saved. Also, despite having produced an average of 2,830 tweets, the accounts almost never interacted with other Twitter users through @replies or @mentions.