Segmentation task
EVENTS, EVENT
We used the unitization task originally reported by NewtsonThe number of meaningful boundaries identified by a participant (i.e., segmentation count), operationalized as the number of times they pressed the keyboard’s spacebar during a video, was recorded. This value was used as a predictor variable, to evaluate whether the number of perceived events influenced participants’ segmentation agreement and memory performance.Segmentation agreement is the degree to which one participant’s identified event boundaries align with those identified by others. In our analyses, we used each activity’s knowledgeable group at post-test (those who went through the related workshop) as the reference group to which all other segmentation similarity values would be compared. This is because the knowledgeable groups for each activity should have the most informed normative event boundaries. In other words, for the Tai chi video, each participant’s event boundaries at pre- and post-test were compared with the boundaries identified in the post-test by those who completed the Tai chi workshop. For the gyoza video, individual’s event boundaries at pre- and post-test were compared to the boundaries identified by the Gyoza group at post-test. This was done so that all segmentation agreement values would be calculated in terms of the same reference point.Segmentation agreement was calculated by fitting a one-second Gaussian Kernel function around each participant’s button press (i.e., each perceived event boundary). By doing so, each frame of the video receives a smoothed likelihood (on a scale of zero to one) that the participant perceived an event boundary on that frame. Normative event boundaries were identified by averaging the event boundary probabilities from each “knowledgeable” participant on the post-test segmentation task. The correlation between each participant’s event boundary probabilities and the knowledgeable group’s normative boundaries was then calculated. Importantly, this was calculated for each video using a leave-one-out procedure––i.e., a participant’s own post-test segmentation responses were not included in the normative boundaries calculated for their comparison. For more on this segmentation agreement calculation, see Pitts et al.