Kids' speech errors: A UG perspective

What explanations does a UG-supporter have for the errors that kids make? Here's a classification I made (derived from a talk of Paola Crisma at the Università di Trieste) 1) The main divide is between Competence and Performance. The primary difference is that Performance errors are less likely to be systematic than the Competence errors. (Of course, probabilistic rules are not excluded.) 2) Some cues might require maturational changes. So, no amount of evidence before a certain age will convince the kids to set certain parameters. 3) ...which brings us to the most interesting (personally!) view, that errors are Competence errors, and they come about by mis-setting parameters. This is a consequence of the Continuity Hypothesis, a version of which we heard in much of Lila's talks. I suppose the Subset Principle of Wexler et al(*) goes under this mis-setting account. However, over the last year and this, I heard little bits of stuff from here and there, which suggest a nice sub-classification of such mis-setting errors

• Errors of omission. These are of the kind discussed by Nina Hyams, for example when you find pro-drop in a non-pro-drop language.
• Errors of commission. These are probably the nicest! We heard some of this last year when Anthony Kroch visited our lab. One example of this is the finding that some English kids do not invert the auxiliary and the subject in wh-questions (so they say "What John had done?")

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*Manzini, R. & Wexler (1987). Parameters, Binding Theory, and learnability. Linguistic Inquiry, 18, 413-444.