TABLE 6.

The definition and calculation of the metrics of interest.

Metric	Definition	Calculated as
Total Fixation Duration (TFD)	The accumulated duration of fixations on a stimulus or an AOI	The sum of the durations of all fixations located on an object or an AOI
Time to First Fixation (TTFF)	The time it takes before a stimulus or AOI is seen	The time that it takes measured from the moment that 50% of the feed post enters the screen until the first fixation lands on that AOI
Percent Seen	The percentage of participants that have at least 1 fixation (= “seen”) on a stimulus or an Area of Interest (AOI)	On a participant level for each AOI, a binary score (SEEN) is assigned (1 or 0, indicating “seen” and “not seen” respectively). This is then aggregated as the percentage of participants that had a minimum of a single fixation on the AOI. This is done by compiling all subjects and taking the percentage of participants who had at least one fixation. For example, if 10 participants were exposed to an AOI and 8 participants saw it for at least one fixation, then %seen would equal 80%, regardless of how long participants viewed the ad for.