These are behavioural data from experiments on children's word learning. The experiments typically assessed children from age 2 to age 4 or 5. Specifically, the projects herein assessed three questions. (1) How do children learn new senses for known words? These studies examined whether knowing one sense of a word supports 3- and 4-year-old children in learning additional senses. Specifically, we examined whether known senses constrain the guesses that children make about new word senses. (2) How do children understand the relations between word senses? for instance, do young children understand that a polysemous word like "chicken" has two meanings (animal versus meat)? Or do they mistakenly infer that "chicken" has a single vague meaning? (3) How do children learn to coin new senses? Many polysemous words can be extended in predictable ways. For example, if you know that a "wuggle" is a type of tool, then you can guess that the action of using the wuggle is called "wuggling". How does this creativity develop? We examined whether children learn rules for coining word senses by analogizing from the polysemous words that they already know.One of the most striking features of human communication is our ability to use words in flexible and creative ways: We often use the same sound to mean multiple different things. For instance, we hammer using a hammer, eat chicken that comes from a chicken, and drink from glasses that are made of glass. These flexible uses of words provide us with a vivid expressive power: we can use a word with one meaning while alluding to all the rest. But while flexibility may make language more expressive, researchers have often assumed that it also makes language harder to learn. In particular, if a word's meaning is a flexible, moving target, then how are children ever supposed to learn it in a reasonable amount of time? This has led a number of researchers to conclude that the words of an "ideal" language would be unambiguous. But in recent work we have developed a theory that suggests this assumption is backwards: Flexible uses of words do not impede children from learning words, in fact, they appear to facilitate it. The theory is best explained by an example. Imagine that you are a parent of a small child, and you want your child to avoid hitting their head on the leg of a nearby table. Your child does not yet know what the leg is called, but has learned that long, straight, supportive body parts are called "legs". When they hear you say "Watch out for the leg" and do not see any relevant body parts, they can guess that "leg" refers to something related to the body part, and thus might have a reasonable chance of guessing what you mean. By contrast, if you had to use a different, unambiguous word for each concept that you wanted to express, you might have to say something like "Watch out for the dax". Since your child has no idea what "dax" means, they are unlikely to be able to heed your warning. Consistent with this, we have uncovered initial evidence that children are able to master flexible language with minimal difficulty. This project aims to understand how children are able to do that, based on a combination of tightly-controlled behavioural research on developing children, and the annotation and analysis of transcripts of children's and parents' speech. First, we will build on and analyze existing databases of children's conversations with parents and others. We will code these databases for some of the particular features of flexible words, and then use advanced statistical methods to examine the linguistic environment that adults provide for children, and how children respond to that environment. Second, we will conduct a series of studies that assess how children between 2- and 4-years manage to learn and understand the different meanings of flexible words, while at the same time keeping these meanings distinct in their heads. For example, how do children learn that "chicken" can label both an animal and a kind of meat, while also understanding that things that are true of the animal need not be true of the meat (and vice versa)? Third, we will conduct experiments to explore how children learn to use flexible words in creative ways that they could not have heard before. Linguists have provided tantalizing examples of children's coinages, from "Broom my mess" to "Cracker my soup". Our experiments will explore how children learn to use words in these ways, providing insight into the origins of the type of linguistic creativity that infuses poetry and oratory. Our final series of studies will examine what the consequences of flexibility are for children's cognitive development more generally. In particular, our theory raises the surprising possibility that the particular ways that flexible words are used in a language may encourage children to learn about the world in specific ways. For example the fact that we "shovel" snow using a "shovel" suggests that shovels are made for shovelling. Our last studies assess whether such linguistic clues affect how children explore and learn about objects.

This deposit links to three bundles of experimental data. Bundle 1 examines how children (aged 3 to 4 yrs) learn new word senses. Bundle 2 examines how children (aged 3 to 4 yrs) represent the senses of known polysemous words. Bundle 3 examines how children (aged 2 to 4) learn to coin new senses for words. Participants in these studies were children aged 2 to 4 years. Participating families were recruited through local preschools, museums, zoos, etc, in the Edinburgh and Berkeley, CA area, as well as through databases of families held at both institutions.