Vibrotactile Similarity Perception in Crowdsourced and Lab Studies.

Crowdsourcing can enable rapid data collection for haptics research, yet little is known about its validity in comparison to controlled lab experiments. Furthermore, no data exists on how different smartphone platforms impact the crowdsourcing results. To answer these questions, we conducted four vibrotactile (VT) similarity perception studies on iOS and Android smartphones in the lab and through Amazon Mechanical Turk (MTurk). Participants rated the pairwise similarities of 14 rhythmic VT patterns on their smartphones or a lab device. The similarity ratings from the lab and MTurk experiments suggested a very strong correlation for iOS devices (r(s) = 0.9) and a lower but still strong correlation for Android phones (r(s) = 0.68). In addition, we found a stronger correlation between the crowdsourced iOS and Android ratings (r(s) = 0.78) compared to the correlation between the iOS and Android data in the lab (r(s) = 0.65). We provide further insights into these correlations using the perceptual spaces obtained from the four datasets. Our results provide preliminary evidence for the validity of crowdsourced VT similarity studies, especially on iOS devices.