4. The computer-implemented method as recited in claim 3 , wherein providing one or more cues, receiving image data responsive to the one or more cues, sending requests for ratings corresponding to the image data, and receiving ratings corresponding to the image data are performed by a computer-based system over a network coupling the computer-based system to the first plurality and second plurality of provider devices.
7. The computer-implemented method as recited in claim 4 , wherein using the classifier comprises programming an electronic device to evaluate images depicting human facial expressions.