Multi-player online battle arena games (MOBAs) are large virtual environments requiring complex problem-solving and social interaction. We asked whether these games generate psychologically interesting data about the players themselves. Specifically, we asked whether user names, which are chosen by players outside of the game itself, predicted in-game behaviour. To examine this, we analysed a large anonymized dataset from a popular MOBA (‘League of Legends’) – by some measures the most popular game in the world. We find that user names contain two pieces of information that correlate with in-game social behaviour. Both player age (estimated from numerical sequences within name) and the presence of highly anti-social words are correlated with the valences of player/player interactions within the game. Our findings suggest that players' real-world characteristics influence behaviour and interpersonal interactions within online games. Anonymized statistics derived from such games may therefore be a valuable tool for studying psychological traits across global populations. 
What's in a name? Ages and names predict the valence of social interactions in a massive online game