"In terms of the methods that we implement, we have a very broad research methodology toolkit," said Tammy Snow, Expedia's director of user experience research. That toolkit includes EMG, "something unique to the way Expedia builds our experiences," Snow said. "We care very much about the emotional impact of experiences." Emotional impact is what EMG measures. Eye-tracking glasses enable a researcher to see what a test subject is looking at, whether it's on a desktop computer or a mobile phone. Sensors placed on the forehead, where one might furrow one's brow, help read feelings of confusion or tension. Sensors placed on the cheeks to read muscles that form smiles enable researchers to recognize when a user is positively responding to something. Get the full story at Travel Weekly