Social networking sites such as Twitter and Facebook should not be used to study human behaviour or trends as they are too subjective.
The warning comes from researchers at McGill University in Montreal and Carnegie Mellon University in Pittsburgh as use of sites by social researchers and media organisations to gather data about public views and interests increases.
Researchers said the gathered information would not reflect the opinion of the majority of individuals who are either under-represented, or those not connected in social media.
"Different social media platforms attract different users – Pinterest, for example, is dominated by females aged 25-34 – yet researchers rarely correct for the distorted picture these populations can produce. Publicly available data feeds used in social media research don’t always provide an accurate representation of the platform’s overall data – and researchers are generally in the dark about when and how social media providers filter their data streams," a report said.
"The design of social media platforms can dictate how users behave and, therefore, what behaviour can be measured. For instance, on Facebook the absence of a "dislike" button makes negative responses to content harder to detect than positive "likes"."
One recent report on Twitter users said just 5% of users are aged over 65 than 35% are aged between 18 and 29.
Men are higher users of social networking sites than women.
"Large numbers of spammers and bots, which masquerade as normal users on social media get mistakenly incorporated into many measurements and predictions of human behaviour. Researchers often report results for groups of easy-to-classify users, topics, and events, making new methods seem more accurate than they actually are.
"For instance, efforts to infer political orientation of Twitter users achieve barely 65% accuracy for typical users – even though studies (focusing on politically active users) have claimed 90% accuracy."