The symbols included single strokes, geometric figures, printed English alphabet letters, and simple Chinese characters, each of which contained one or two designated target characteristics. The results showed that the threshold superimposability for tracing was about 50 percent, above which ceiling the probability that a questioned sample had been traced was high. The subjects were also asked to sign their signatures on a piece of white paper placed on the pressure plate of a writing pressure meter. The writing pressure variation patterns between written and traced signatures showed that tracings featured slow, measured strokes accompanied by hesitation, pen pauses, and the absence of spontaneity. While the participants could trace the general shape and effect of the targeted symbols, they ignored the writing details. 3 figures, 12 tables, and 6 references