Examining relationships between input and language development: some statistical issues

Abstract

With various descriptions of adults' speech to children in hand, investigators have turned their attention to questions concerning the specific nature and extent of relationships between aspects of input and language development. Answering such questions requires some conceptualization of the potential relationships that may exist. Equally important, though, are the statistical and design issues surrounding the inference of these relationships. An exhaustive discussion of these issues is beyond the scope of this Note. Consequently, we will focus on three specific topics: (1) the use of gain scores; (2) aspects of correlation and alternative procedures that have an impact on the validity and interpretability of statistical findings; and (3) passive observation versus experimental manipulation.