Limitations on Reliability: Regularity Rules in the English Plural and Past Tense


  • The research was supported by National Institute of Child Health and Human Development Grant HD-053403 to V.K.J. We thank the children, parents, and teachers who participated in these studies. Thanks also to Christin Chambers and Sarah Puckett for assistance in collecting and coding data and to Eve Clark for helpful comments on a previous draft.

concerning this article should be addressed to Vikram K. Jaswal, Department of Psychology, University of Virginia, 102 Gilmer Hall, P.O. Box 400400, Charlottesville, VA 22904-4400. Electronic mail may be sent to


Two studies investigated 3- to 5-year-olds’ trust in a reliable informant when judging novel labels and novel plural and past tense forms. In Study 1, children (N = 24) endorsed the names of new objects given by an informant who had earlier labeled familiar objects correctly over the names given by an informant who had labeled the same objects incorrectly. In Study 2, children (N = 24) endorsed novel names given by an informant who had earlier expressed the plural of familiar nouns correctly over one who had expressed the plural incorrectly. But children overwhelmingly endorsed the regular plural and past tense forms of new words provided by the formerly unreliable labeler (Study 1) or morphologist (Study 2) rather than irregular forms of those words provided by the formerly reliable informant.