A Comparison of Two Linguistic Sign Identification Methods

This paper employs two linguistic sign identification methods - a manual one focusing on the dominant hand and a nonmanual one focusing on the mouth - and compares the kinds of sequences they classify as signs from a video containing continuous signing. The study is motivated by two projects, of which one investigates the ontological nature of the sign and the other aims to develop an automatic sign recognition tool. In the study, both methods were able to associate all the free semantic-functional elements in the data with signs. However, in the nonmanual method the overall number of identified signs was lower because the stretching of the mouth movement of the semantic element over the following pointing meant that the combinations of semantic elements and pointings were counted as single signs. Moreover, signs identified by the nonmanual method were longer than those identified by the manual method. The results from the nonmanual method agree with the claim that phrase internal sequences of semantic elements and pointings are lexical head plus clitic combinations. Consequently, it is suggested that pointings in such contexts do not need to be independently detected by the automatic sign recognition tool.