DELV™ Author Team

Tom Roeper is a linguist at UMass who works in the generative tradition both at the theoretical and experimental level. Over the past 50 years his primary focus has been articulating both the theory and facts to give us an understanding of the acquisition path as part of Universal grammar, exploring phenomena like recursion and movement. His extensive cross-linguistic work falls within the larger quest to explore the foundations and implications of Cognitive Science. These projects have led to applied work in Communication Disorders, second language acquisition, and heritage languages. He contributed to the DELV assessment that seeks to respect dialect variation, especially African-American English, in evaluation of disorders. He also pursues the pedagogical implications for education about grammar and in second language acquisition. His goal is to discover how we can directly apply experimental insights in nursery and elementary curricula, as well as enriching our language interactions with children.

Harry N. Seymour earned his Ph.D. from the Ohio State University, and is now Professor Emeritus and former Chairman of the Department of Communication Disorders at the University of Massachusetts Amherst. Author of over 40 articles and 100 presentations, he is lead author of the Diagnostic Evaluation of Language Variation (DELV). A Fellow of the American Speech-Language Hearing Association (ASHA) and the Kellogg National Fellowship Program he is also the recipient of the Distinguished Alumni Award, School of Communications, Howard University; the Honors of the National Black Association of Speech, Language and Hearing; the Multicultural Service Award, (ASHA); the editor’s Award: Language, Speech and Hearing Services in Schools; and in 2003, he was presented the highest recognition from his professional association—the Honors of the ASHA.
In 2018, he was inducted into the HistoryMakers, a repository for the nation’s largest African American video oral history collection.

Jill de Villiers is a Professor Emerita at Smith College in Psychology and Philosophy. Though she trained in Experimental Psychology at Harvard, her work has also contributed to Linguistics by testing theoretical ideas with experimental work with children. Dr. de Villiers’ specialty is language acquisition, including several books on language acquisition as well as over a hundred articles on many varied topics within the field. She has an abiding interest in the path that preschool children take to learn complex grammar, and its relationship to “theory of mind”, namely how children understand what other people know, think, believe and feel. She has designed language assessments in several languages, and is passionate about inventing interesting interventions for children having problems. She has lectured and given week-long workshops on language acquisition and assessment all over the world, including Brazil, Japan, China, France, Germany, Spain, South Africa, the Netherlands, Uzbekistan and the UK.

Peter de Villiers studied Psychology and Philosophy at Oxford University on a Rhodes Scholarship from South Africa. After a BA at Oxford in 1970, he earned a Ph.D. in Experimental Psychology in 1974, and then spent five years on the faculty at Harvard. He has been at Smith College since 1979, and is now the Sophia and Austin Smith Professor Emeritus of Psychology.
de Villiers’ research has focused on first language acquisition, especially pragmatics knowledge, in both typically-developing and deaf children, on the relationship between language acquisition and reading, and on the effects of language on theory of mind development. He is the co-author of two textbooks and a film on first language acquisition and of a hands-on science and language arts curriculum for deaf children. He developed the pragmatics subtests for the Diagnostic Evaluation of Language Variation Norm-referenced test (DELV-NR, Seymour, Roeper, & de Villiers, 2005). His current projects include the study of various aspects of pragmatics and communication in high-functioning children with autism spectrum disorders.

Barbara Zurer Pearson received a B.A. in French from Middlebury College (including a year in France at the Sorbonne), a Masters in TESOL (Teaching English to Speakers of Other Languages) from Florida International, and the Ph.D. in Applied Linguistics from the University of Miami (FL). She taught and did research with the University of Miami Bilingualism Study Group for 20 years before moving to the University of Massachusetts Amherst, where she has been a Research Associate in Linguistics and Communication Disorders.
In addition to many scholarly publications on bilingual and bi-dialectal child language acquisition, she participates in “Language Science for Everyone” activities, and wrote a book for parents, Raising a Bilingual Child (Random House, 2008), which is also published in Spanish, Polish and Chinese (2010, 2013, 2015). She was Project Manager, and now a co-author, of the Diagnostic Evaluation of Language Variation tests.