1. A computer-implemented method comprising: receiving sensor data for a person, the sensor data passively sensed during presentation of a media program to the person; determining, based on the sensor data, a state of the person during the media program, the state being a sad, a related talking, an unrelated talking, a disgusted, an afraid, a smiling, a scowling, a placid, a surprised, an angry, a laughing, a screaming, a clapping, a waving, a cheering, a looking-away, a looking-toward, a leaning-away, a leaning-toward, an asleep, or a departed state; and providing the state of the person effective to enable measurement of a value of the media program, assessment of a potential value of a similar media program or portion thereof, control of presentation of the media program, or automatic rating, for the person, of the media program.