CMU study analyzes what China deletes

Salt is one word bitter to censors
March 8, 2012 12:01 am

Share with others:

Iodized salt isn't typically considered a dangerous chemical compound, but to Chinese social media censors hoping to squash rumors that the substance could prevent radiation poisoning following last year's nuclear disaster in Japan, the term became downright unspeakable.

"The Chinese government came in, put their foot down and said don't believe these rumors. After that, iodized salt became a sensitive topic and it was highly likely a message would be deleted if it discussed salt," said David Bamman, a Ph.D. candidate at Carnegie Mellon University's Language Technology Institute and co-author of the study, "Censorship and Deletion Practices in Chinese Social Media."

"Iodized salt," "brainwash" and "Falun Gong," a religion declared a cult and banned by the Chinese government in 1999, were among thousands of terms that triggered censorship when used in social media last year, according to the CMU study.

Mr. Bamman, along with Brendan O'Connor, a Ph.D. student in CMU's Machine Learning Department, and CMU Professor Noah Smith focused on content from Chinese micro-blogging service Sina Weibo to gauge the likelihood that messages with politically charged words, names and phrases will be deleted by either private or public censors.

Sina Weibo is one of the most popular microblogging sites in China and one of the most active in the world, surpassing Twitter's usership with more than 200 million accounts. In 2009, the Chinese government blocked citizens' access to Twitter and Facebook.

"A lot of studies have focused on censorship that blocks access to Internet sites, but the practice of deleting individual messages is not yet well understood," Mr. Smith said. "The rise of domestic Chinese micro-blogging sites has provided a unique opportunity to systematically study content censorship in detail."

The team studied approximately 57 million messages sent on Sina Weibo between June 27 and Sept. 30 last year, using a programming application the company provides to developers to create related content.

Three months later, through the same application, the researchers checked a random set of "Weibos," as well as a set that included politically charged messages, to see if any had been deleted.

First Published 2012-03-07 23:36:10

Join the conversation:

Commenting policy | How to report abuse
Commenting policy | How to report abuse
To report inappropriate comments, abuse and/or repeat offenders, please send an email to and include a link to the article and a copy of the comment. Your report will be reviewed in a timely manner. Thank you.
PG Products