analyzing physiological data from a plurality of viewers exposed to {TAIL ~ media} to define a plurality of {HEAD ~ events} in the media and to derive a plurality of physiological response dimensions from the physiological data for the plurality events 
analyzing physiological data from a plurality of viewers exposed to { TAIL ~ media } to define a plurality of { HEAD ~ events } in the media and to derive a plurality of physiological response dimensions from the physiological data for the plurality events
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH