"Maybe it was a joke": emotion detection in text-only communication by non-native english speakers

Previous studies have shown that people can effectively detect emotions in text-only messages written in their native languages. But is this the same for non-native speakers' In this paper, we conduct an experiment where native English speakers (NS) and Japanese non-native English speakers (NNS) rate the emotional valence in text-only messages written by native English-speaking authors. They also annotate all emotional cues (words, symbols and emoticons) that affected their rating. Accuracy of NS and NNS ratings and annotations are calculated by comparing their average correlations with author ratings and annotations used as a gold standard. Our results conclude that NNS are significantly less accurate at detecting the emotional valence of messages, especially when the messages include highly negative words. Although NNS are as accurate as NS at detecting emotional cues, they are not able to make use of symbols (exclamation marks) and emoticons to detect the emotional valence of text-only messages.