(Ph.D. University of California, Berkeley) is Gerhard Helbig Professor of German as a Foreign Language and Applied Linguistics at the University of Leipzig and President of the Institute for Test Research and Test Development in Leipzig, Germany. Before joining the University of Leipzig, he taught at the University of Iowa, Iowa City (1990-1998) and at the University of Michigan, Ann Arbor (1988 1990). His main research areas are: second language acquisition, corpus linguistics, language testing and assessment, and language policy. He is (co-) author of over 150 books, book chapters, and journ...