A Corpus-based Study of Productivity of Derivational Prefixes in the Written Variety of Contemporary Persian

One of the significant issues in morphology, generally and in word-formation processes, especially is productivity. Most researchers consider productivity as a gradient concept and define it in a continuum. The present research is about to answer three questions below: 1. what are the rankings of the studied prefixes in terms of productivity? 2. Which of the prefixes is category-preserving and which one is category-changing? 3. What is the prototypical input of each prefix? In order to answer the questions, first, 19 derivational prefixes of Persian were selected based on the works in which Persian derivational prefixes had been presented. Then, the data of the research were extracted from the 150 million words corpus of Hamshahri 2 by the AntConc software and after that they were transferred to Excel program to be tagged and analyzed based on Baayen's (2009) global productivity measure and Rosch's (1975, 1977, 1978) prototype theory. The results showed that /Gejr/ is the most and /bol/ is the least productive prefixes of Persian language. For answering the second and third questions, each prefix was studied independently by the chi-square statistical test in SPSS software and the category-changing or category-preserving features of each prefix were specified. Also, the prototypical lexical category of each prefix input were identified.