2051	 A PL I Program to Assist the Comparative Linguist	 A practical PL I program is described which can assist comparative linguists to determine the regular sound correspondences between genetically related languages. The investigator must arrange data for input by aligning pairs of suspected cognates. The program tabulates the correspondences and uses list processing techniques to sort and count them. Each pair of words is then assigned a relative value that is a function of the total frequency in the data of each correspondence found in that pair of words. The output is a list of all correspondence types with their frequency of occurrence in the data and a separate listing of each correspondence with all word-pairs showing that correspondence unless their relative value is below an arbitrarily chosen cutoff point . The article explains the usefulness as well as the limitations of the programs and illustrates its use with a small portion of hypothetical data. comparative linguistics natural language processing comparative method historical linguistics diachronic linguistics genetic relationship sound change sound correspondence regular correspondence list processing
