1 Improving Source Code Lexicon via Traceability and Information Retrieval Andrea De Lucia ∗ , Massimiliano Di Penta † , Rocco Oliveto ∗ ∗ Department of Mathematics and Informatics - University of Salerno, Via Ponte don Melillo - 84084 Fisciano (SA), Italy † Department of Engineering, University of Sannio, Viale Traiano - 82100 Benevento, Italy adelucia@unisa.it, dipenta@unisannio.it, roliveto@unisa.it April 9, 2010 DRAFT Digital Object Indentifier 10.1109/TSE.2010.89 0098-5589/10/$26.00 © 2010 IEEE IEEE TRANSACTIONS ON SOFTWARE ENGINEERING This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication.