Crowd numbers are notoriously difficult to estimate, as I learnt when I worked as a political reporter in the 1990s. It is very easy to over-estimate the size of a political rally, especially if the organisers feed wildy inaccurate estimates to the media. When bloggers and Twitterers jump in, the inaccuracies are easily exaggerated, as Megan Garber persuasively demonstrates in an excellent article in the Columbia Journalism Review (“…the evolution of an error“). According to Garber, the organiser of the Freedomworks rally fed misinformation to his followers, who enthusiastically perpetuated and exaggerated the error in their blogs and Tweets.
Interestingly, as Garber points out, the saga confirms that trust in the mainstream media is at an all-time low. Ironically, the mainstream media in this case got the facts mostly right, unlike the bloggers!