The Chinese version of Twitter is a microblogging service called
Weibo which launched in 2010. This allows users to post 140
character messages with @usernames and #hashtags, just like
Twitter– although 140 characters in Chinese contain
significantly more information content than in English. In just
three years, Weibo has picked up some 300 million users who
between them send 100 million messages each day at the rate of
70,000 per minute. That makes the inevitable process of
censorship a tricky task for the Chinese authorities. So an
interesting question is how they do it. Today,Dan Wallach at
Rice University in Houston, Texas, and a few pals reveal the
results of a detailed study of censorship on Weibo. Their method
has allowed them to reconstruct the censorship techniques used
by the government, to calculate the number of workers who must
be involved and even to discover their daily work schedules. The
work is possible because at least some of the content on Weibo
is not censored prior to publication, only