I have also found 3 or 4 subjects suitable for using NRL game footage as stimulus. At this point I will have to start looking into how I will acquire footage for an entire match.
Currently the plan is to use a 40 minute video segment (half a game) followed by 40 minutes of annotation, with 10 minutes changeover and setup. 90 minutes seems reasonable, but there may not be enough data for all different classifier combinations.
If there aren't enough data points, I might see if I lengthen each experiment session or do physiological recording and self-annotation stages in separate sessions. There are issues with either decision:
- By lengthening the recording sessions, I will gain more data points, which will probably increase the experiment's accuracy. On the other hand, if the session is too long (as I experienced in the siento experiments I participated in earlier) the subject can lose interest/concentration which could yield varying results.
- By splitting two stages up, I gain more data points and the subject will be 'fresh' for each session. However, the subject's emotional state may change from each session, especially if they cannot remember their emotional response during the session when annotating footage.
I will finalise a decision after testing the video annotation software against half a match of an NRL game and seeing how many data points are recorded.