We studied handwriting recognition in an X-AB task, by asking participants to discriminate if a handwritten target word was produced by the same writer as one of two comparison words, shown in left/right positions. Three types of writers have been considered: self, best friend, stranger. We collected a large sample of handwritten words by 10 pairs of best-friend children, attending 3rd and 5th primary school classes, and tested every child individually after 1 and 2 months, using the following AB pairs: self vs. best friend; self vs. stranger; best friend vs. stranger; stranger vs. another stranger. Therefore, discrimination could benefit from three factors: agency (present only in self handwritings), familiarity (present in self and best-friend, but not stranger, handwritings), and form similarity (differentiating various handwritings). Agency and familiarity effects were revealed by the superiority of performance in trials in which self and best-friend handwritings were compared to stranger handwritings, over those involving the handwritings of two different strangers. Taking discrimination accuracy by stranger participants as a dissimilarity value, we used a multidimensional scaling approach to find the relative distances of the 20 handwritings. Such distances were significantly distorted by agency and familiarity (i.e.; distances were modified when AB pairs involving self and best-friend handwritings were considered). Children data confirmed previous results obtained in our lab with university students, using a similar paradigm, as well as conclusions by Chen et al. (2008) in their study on the identification of Chinese handwritings.
