They say you can tell a lot by a person’s friends, but when it comes to social media, it seems you can tell a lot by who you choose to follow.

New research shows that when it comes to Twitter, the people you follow can have a great impact on how you act online. According to researchers at the University of Southern Carolina, Twitter users are more likely to tweet in line with the people they follow. So if you follow a lot of angry, hateful or negative Twitter users, you might want to start ramping up the comedic, positive forces in your feed. Labelling the effect as “emotional contagion”, lead researcher Dr Emilio Ferrara explained: "What you tweet and share on social media outlets matters. Often, you're not just expressing yourself - you're influencing others.” Analysing the accounts of more than 3,800 Twitter users, the researchers monitored the sentiment of accounts from the language used in their posts. Among the negative tweets, expressions of anger and fear were predominant in the messages. So what is the average Twitter using posting? According to the team, the average feed is made up of 34.4 per cent positive, 48.3 per cent neutral and 17.3 per cent negative tweets. The study also found that very few people are not influenced by their Twitter feed at all – with just a fraction of samples from the study remaining uninfluenced by the sentiment of the feed around them. This was in contrast to 20 percent of users being ‘highly susceptible’ to the tweeting behaviour of their online companions. This could result in higher levels of negative tweets, if they follow feeds where the sentiment is shaped to this viewpoint. These highly susceptible users are far more likely to be influenced by positive feeds than negative ones, the researchers claimed.