Benefits of reflex prediction: a case study of Western Kho-Bwa

While analysing lexical data of Western Kho-Bwa languages of the Sino-Tibetan or Trans-Himalayan family with the help of a computer-assisted approach for historical language comparison, we observed gaps in the data where one or more varieties lacked forms for certain concepts. We employed a new workflow, combining manual and automated steps, to predict the most likely phonetic realisations of the missing forms in our data, by making systematic use of the information on sound correspondences in words that were potentially cognate with the missing forms. This procedure yielded a list of hypothetical reflexes of previously identified cognate sets, which we first preregistered as an experiment on the prediction of unattested word forms and then compared with actual word forms elicited during secondary fieldwork. In this study we first describe the workflow which we used to predict hypothetical reflexes and the process of elicitation of actual word forms during fieldwork. We then present the results of our reflex prediction experiment. Based on this experiment, we identify four general benefits of reflex prediction in historical language comparison. These comprise (1) an increased transparency of linguistic research, (2) an increased efficiency of field and source work, (3) an educational aspect which offers teachers and learners a wide plethora of linguistic phenomena, including the regularity of sound change, and (4) the possibility of kindling speakers’ interest in their own linguistic heritage.