Despite many media outlets increasingly referring to Twitter ‘outrage’ to support current affairs stories, the social network is not an indicator of overall public opinion.

According to a year-long study by the Pew Research Center, “the reaction on Twitter to major political events and policy decisions often differs a great deal from public opinion as measured by surveys”.

This, the research claims, is down to both the “narrow sliver” of the public represented on Twitter, as well as who among that group choose to take part in any one conversation.

The study finds that Twitter reactions are frequently more pro-Democratic or liberal than the balance of public opinion. For example, when Obama was re-elected, positivity on Twitter measured 77%, compared to ‘happy public opinion’, which measured 52%. Similarly, when a law was passed allowing same-sex marriage in California, favourable opinion on Twitter measured 46% compared to 33% within public opinion.

However, the study did find cases where Twitter reactions were more conservative than public opinion. During Obama’s second inaugural speech for example, where Twitter positivity measured just 13% compared to public opinion with 48%.

Pew attributes this disconnect between public opinion and Twitter opinion to the fact that “those who get news on Twitter – and particularly those who tweet news – are very different demographically from the public”. Accordingly, just 13% of adults say they ever use Twitter and only 3% said they regularly or sometimes tweet or retweet news items.

Furthermore, Twitter users are not representative of the public overall. Users are generally considerably younger than the general public, and more likely to lean towards the Democratic Party.

Finally, the Twitter users that choose to share their opinion on events vary with the topics in the news. For example, those who tweeted about the California same-sex ruling were not likely to be the same group that tweeted about Romney and Paul Ryan.

Strong evidence then, that just because Twitter says it doesn’t mean it’s true!