But the real test is how does it stack up. Li and the team pitted the algorithm against lowly humans, having both watch videos of just micro expressions. Participants were instructed to identify which emotion went with which expression. Team human was about 72 percent accurate, and the computer's best accuracy was about 82 percent. The second task involved picking out micro expressions from a longer video. The researchers made it easier on humans (allowing them to replay the videos, and only having them note how many micro expressions they saw, not when they saw them), since they felt the task was "too difficult." Even with that advantage, humans scored an accuracy of about 50 percent, while the computer earned a comparable 42 percent.