Similarity-based and rule-based accounts of cognition are often portrayed as opposing accounts. In this paper we suggest that in learning and development, the process of comparison can act as a bridge between similarity-based and rule-based processing. We suggest that comparison involves a process of structural alignment and mapping between two representations. This kind

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Theories of categorization have typically focused on the internal structure of categories. This paper is concerned with the external structure of categories. In particular , it is suggested that many categories specify the relational role that is played by category members. To support this claim, the paper distinguishes between traditional feature-based categories, relational categories (which specify a relational structure) and role-governed categories (which specify that an item plays a particular role within a relational structure). After discussing the relationship among these types of categories, the implications of this view for the study of category learning and category use are discussed.

This paper describes a cross-disciplinary extension of previous work on inferring the meanings of unknown verbs from context. In earlier work, a computational model was developed to incrementally infer meanings while processing texts in an information extraction task setting. In order to explore the space of possible predictors that the system could use to infer verb meanings, we performed a statistical analysis of the corpus that had been used to test the computational system. There were various syntactic and semantic features of the verbs that were significantly diagnostic in determining verb meaning. We also evaluated human performance at inferring the verb in the same set of sentences. The overall number of correct predictions for humans was quite similar to that of the computational system, but humans had higher precision scores. The paper concludes with a discussion of the implications of these statistical and experimental findings for future computational work. Introduction Ver...

Is our knowledge about the appearance of objects more closely related to verbal thought or to perception? In a behavioural study using a property verification task, Kosslyn (1976) reported that there are both amodal and perceptual representations of concepts, but that amodal representations may be more easily accessed. However, Solomon (1997) argued that due to the nature of Kosslyn’s stimuli, subjects may be able to bypass semantics entirely and perform this task using differences in the strength of association between words in true trials (e.g., cat–whiskers) and those in false trials (e.g., mouse–stinger). Solomon found no evidence for amodal representations when the task materials were altered to include associated false trials (e.g., cat–litter), which require semantic processing, as opposed to associative strategies. In the current study, we used fMRI to examine the response of regions of visual association cortex while subjects performed a property verification task with either associated or unassociated false trials. We found reliable activity across subjects within the left fusiform gyrus when true trials were intermixed with associated false trials but not when true trials were intermixed with unassociated false trials. Our data support the idea that conceptual knowledge is organised visually and that it is grounded in the perceptual system. One of the leading theories of the organisation of

Why do children learn nouns such as cup faster than dimensional adjectives such as big? Most explanations of this phenomenon rely on prior knowledge of the noun-adjective distinction or on the logical priority of nouns as the arguments of predicates. In this paper we examine an alternative account, one which relies instead on properties of the semantic categories to be learned and of the word learning task itself. We isolate four such properties: the relative size, the relative compactness, and the degree of overlap of the regions in representational space associated with the categories and the presence or absence of lexical dimensions (what color? ) in the linguistic context of a word. In a set of five experiments, we trained a simple connectionist network to label input objects in particular linguistic contexts. The network learned categories resembling nouns with respect to the four properties faster than it learned categories resembling adjectives. Young children learn nouns more ...

Introduction This research examines how children begin learning the meanings of words. Necessarily, novice word-learners must start by pairing a word form with the scenes in which it occurs, collecting several such pairs, and then identifying the common element in the scenes. Before children have learned many words or any language specific syntax, this extralinguistic context is the only information source they can draw on. However, there has been relatively little research on the details of cross-situational observation. We do not know just how much information is actually available in the extralinguistic contexts of word use. Nor do we know how the properties of this information source might shape what children learn in the initial stages of vocabulary acquisition or the process by which they learn it. The studies that follow begin to address these questions. They focus exclusively on the informational content of the input. They do not explore whether this information is accessible

Why do children learn nouns such as cup faster than dimensional adjectives such as big? Most explanations of this well-known phenomenon rely on prior knowledge in the child of the nounadjective distinction or on the logical priority of nouns as the arguments of predicates. In this paper we examine an alternative account, one which seeks to explain the relative ease of nouns over adjectives in terms of the response of the learner to various properties of the semantic categories to be learned and of the word learning task itself. We isolate four such properties: the relative size and the relative compactness of the regions in representational space associated with the categories, the presence or absence of lexical dimensions in the linguistic context of a word (what color is it? vs. what is it?), and the number of words of a particular type to be learned. In a set of five experiments, we trained a simple connectionist categorization device to label input objects, in particular ...

rnating verbs in English (4) a. John stuffed feathers into the pillow Figure-frame b. John stuffed the pillow (with feathers) Ground-frame also, "paint", "wrap", or "stuff" Kim, Landau, and Phillips, BUCLD 23 11/7/98 2 . But.... The existence of cross-linguistic differences in the syntax of locative verbs undermines learning strategies based on universal mapping between syntax and semantics. Syntactic pattern of "fill"-class verb in Korean: Alternators (5) a. Yumi-ka mul-ul cep-e chaywu-ess-ta Nom water-Acc cup-Loc fill-past-Decl `*Yumi filled water into the container.' Figure-frame b. Yumi-ka cep-ul mul-lo chaywu-ess-ta Nom cup-Acc water-with fill-past-Decl `Yumi filled the container with water.' Ground-frame Syntactic pattern of "pile"-class verb in Korean: Figure verbs (6) a. Yumi-ka chaek-ul chaeksang-ey ssa-ass-ta Nom book-Acc table-Loc pile-past-Decl 'Yumi piled the books on the table.' Figure-frame b.

Whether particular arguments are overtly realized in languages like English is not random. A number of researchers have put forward sweeping generalizations in order to capture certain general tendencies. In this paper, however, it is argued that these analyses underestimate the role of constructions, detailed lexical semantics and discourse factors. Given sufficient attention to these factors, the general tendencies, as well as productive classes of systematic exceptions, follow without additional grammatical stipulation. 1.