\input zb-basic \input zb-ioport \iteman{io-port 05977413} \itemau{Edlund, Jens; Al Moubayed, Samer; Beskow, Jonas} \itemti{The Mona Lisa gaze effect as an objective metric for perceived cospatiality.} \itemso{Vilhj\'almsson, Hannes H\"ogni (ed.) et al., Intelligent virtual agents. 11th international conference, IVA 2011, Reykjavik, Iceland, September 15--17, 2011. Proceedings. Berlin: Springer (ISBN 978-3-642-23973-1/pbk). Lecture Notes in Computer Science 6895. Lecture Notes in Artificial Intelligence, 439-440 (2011).} \itemab Summary: We propose to utilize the Mona Lisa gaze effect for an objective and repeatable measure of the extent to which a viewer perceives an object as cospatial. Preliminary results suggest that the metric behaves as expected. \itemrv{~} \itemcc{} \itemut{copresence; face-to-face interaction} \itemli{doi:10.1007/978-3-642-23974-8\_52} \end