Shin and Mill (2021) propose four steps children go through when learning "variable form use." Although I applaud Shin and Miller's focus on morphosyntactic variation, their accrual of evidence is post hoc and selective. Fortunately, Shin and Miller recognize this and encourage tests of their ideas. In support of their work, I share data…

When acquiring the English plural, children correctly produce plural words long before they develop an understanding of morphological structure. When acquiring Sesotho noun prefixes, children are aware of the multiple constraints governing variation from a young age. Both of these cases raise questions about the Shin and Miller (2022) account of…

Languages exhibit variation at all linguistic levels, from phonology, to the lexicon, to syntax. Importantly, that variation tends to be (at least partially) conditioned on some aspect of the social or linguistic context. When variation is unconditioned, language learners regularize it -- removing some or all variants, or conditioning variant use…

In a variety of domains, adults who are given input that is only partially consistent do not discard the inconsistent portion (regularize) but rather maintain the probability of consistent and inconsistent portions in their behavior (probability match). This research investigates the possibility that adults probability match, at least in part,…

In this paper we investigate the effect of variable input on the acquisition of grammar. More specifically, we examine the acquisition of the third person singular marker -s on the auxiliary "do" in comprehension and production in two groups of children who are exposed to similar varieties of English but that differ with respect to adult…