A factorization procedure for finite algebras

A procedure is developed for decomposing any finite algebra into a minimal set of maximally independent simple homomorphic images, or factors, of the algebra. The definition of admissible sets of factors is made in relation to the congruence lattice of the algebra, and generalises the notion of an irredundant reduction in a modular lattice. An algorithm for determining all possible sets of factors of a given finite algebra is derived and an index for measuring the degree of independence of factors is defined. Applications of the technique to finite algebraic models within the social psychological domain are presented and include factorizations for certain semigroups of binary relations and for a class of finite semilattices.     

Teaching autistic children to use extra-stimulus prompts

Autistic children often do not transfer from extra-stimulus prompts, and thus do not utilize a frequent learning aid. It has been hypothesized that this is due to stimulus overselectivity; a failure to respond to simultaneous multiple cues. This study was designed to determine if autistic children who initially respond only to single cues can be taught a set to respond to two cues and subsequently utilize an extra-stimulus (pointing) prompt. Four autistic children were pretested to determine if they could learn a complex visual discrimination by either trial and error or an extra-stimulus prompt fading procedure. Since they did not, the children were then taught to respond to two cues through a multiple-cue training procedure and subsequently tested to determine if they could now utilize a pointing prompt. Results indicated that while all four children initially did not transfer from an extra-stimulus (pointing) prompt, they did so subsequent to multiple-cue training. The results are discussed in terms of implications for treatment (remediating overselectivity) and in relation to normal child development.     

Understanding and appreciating metaphors

We consider three theories that have dominated discussions of metaphor. One view is that metaphors make comparisons, the basis for the comparison being the features (or categories) that the terms of the metaphor share. The second view is that metaphors involve an anomaly. The third view is that metaphors are ‘interactive’, producing a new way of seeing the terms. We propose a new theory—the domains-interaction view—that draws on elements of all three earlier views, but borrows especially from the interaction view. We consider the implications of our theory for three questions: What are metaphors? How are they understood? What makes a good metaphor? We argue that metaphors correlate two systems of concepts from different domains. The best metaphors involve two diverse domains (more distance between domains making for better metaphors) and close correspondence between the terms within those domains. We call the degree of correspondence within-domain similarity. Metaphors are interpreted in several stages: the terms of the metaphor are encoded; the domains involved are inferred; the structures to be seen as parallel are found; the correspondences between these structures are ‘mapped’ or constructed; the terms of the metaphor are compared. If the terms are not seen to match or occupy analogous roles in their different domains, then the metaphor may be reinterpreted. The evidence on all this is tentative but supports our view. We review two studies (Tourangeau and Sternberg, 1981) that support the hypothesis that distance within domain relates negatively to aptness, whereas distance between domains relates positively. Several studies on comprehension tend to disconfirm the comparison theory's notion that the tenor and vehicle necessarily share features. Tenor and vehicle also appear to have asymmetrical roles in the interpretive process.     

Functional constraints on sentence processing: A cross-linguistic study

English and Italian provide some interesting contrasts that are relevant to a controversial problem in psycholinguistics: the boundary between grammatical and extra-grammatical knowledge in sentence processing. Although both are SVO word order languages without case inflections to indicate basic grammatical relations, Italian permits far more variation in word order for pragmatic purposes. Hence Italians must rely more than English listeners on factors other than word order. In this experiment, Italian and English adults were asked to interpret 81 simple sentences varying word order, animacy contrasts between the two nouns, topicalization and contrastive stress. Italians relied primarily on semantic strategies while the English listeners relied on word order—including a tendency to interpret the second noun as subject in non-canonical word orders (corresponding to word order variations in informal English production). Italians also made greater use of topic and stress information. Finally, Italians were much slower and less consistent in the application of word order strategies even for reversible NVN sentences where there was no conflict between order and semantics. This suggests that Italian is ‘less’ of an SVO language than English. Semantic strategies apparently stand at the ‘core’ of Italian to the same extent that word order stands at the ‘core’ of English. It is suggested that these results pose problems for claims about a ‘universal’ separation between semantics and syntax, and for theories that postulate a ‘universal’ priority of one type of information over another. Results are discussed in the light of the competition model, a functionalist approach to grammar that accounts in a principled way for probabilistic outcomes and differential ‘weights’ among competing and converging sources of information in sentence processing.     

On the study of statistical intuitions

The study of intuitions and errors in judgment under uncertainty is complicated by several factors: discrepancies between acceptance and application of normative rules; effects of content on the application of rules; Socratic hints that create intuitions while testing them; demand characteristics of within-subject experiments; subjects' interpretations of experimental messages according to standard conversational rules. The positive analysis of a judgmental error in terms of heuristics may be supplemented by a negative analysis, which seeks to explain why the correct rule is not intuitively compelling. A negative analysis of non-regressive prediction is outlined.     

Blowing in the wind: Perceiving structure in trees and bushes

When lights are mounted at the ends of the limbs of a tree and the surround darkened such that branches and trunk are not visible, viewers can nonetheless make systematic and precise judgments about the unseen structure of the tree through its motion. They seem to perform this task by picking up information about the relative arborization of the tree through the vector paths of the lights on the limbs. Theoretically speaking, the focus of this study is on the perception of second-order centers of moment; previous studies have focused on the perception of first-order centers. A second-order center in a tree-like structure is the location where limb meets trunk, and it is these that perceivers can infer from the dynamic display. The importance of this study is to demonstrate further that the study of centers of moment makes possible a detailed and differential study of event perception.     

Automatic access of the meanings of ambiguous words in context: Some limitations of knowledge-based processing

Five experiments are described on the processing of ambiguous words in sentences. Two classes of ambiguous words (noun-noun and noun-verb) and two types of context (priming and nonpriming) were investigated using a variable stimulus onset asynchrony (SOA) priming paradigm. Noun-noun ambiguities have two semantically unrelated readings that are nouns (e.g., PEN, ORGAN); noun-verb ambiguities have both noun and verb readings that are unrelated (e.g., TIRE, WATCH). Priming contexts contain a word highly semantically or associatively related to one meaning of the ambiguous word; nonpriming contexts favor one meaning of the word through other types of information (e.g., syntactic or pragmatic). In nonpriming contexts, subjects consistently access multiple meanings of words and select one reading within 200 msec. Lexical priming differentially affects the processing of subsequent noun-noun and noun-verb ambiguities, yielding selective access of meaning only in the former case. The results suggest that meaning access is an automatic process which is unaffected by knowledge-based (“top-down”) processing. Whether selective or multiple access of meaning is observed largely depends on the structure of the ambiguous word, not the nature of the context.     

Sign-based short-term coding of American Sign Language signs and printed English words by congenitally deaf signers

A short-term serial recall task consisting of lists of five American Sign Language signs and lists of five printed English words was administered to eight congenitally deaf subjects. For both modes of presentation, the stimuli in a given list were (1) high in phonological relatedness, (2) high in cherological relatedness (i.e., they were similar in terms of the formational attributes of their sign-equivalents), or (3) low in both phonological and cherological similarity (control). For both modes of presentation, recall accuracy was significantly lower on cherologically related lists than on both phonologically related lists and control lists. Phonologically related lists did not differ significantly from control lists. These results suggest the possibility that ways of looking at human memory which rely on a preference for phonological coding in short-term memory processes may reflect the audiocentricity of the experimenter rather than the inherent nature of such processes.     

Illusory conjunctions in the perception of objects

In perceiving objects we may synthesize conjunctions of separable features by directing attention serially to each item in turn (A. Treisman and G. Gelade, Cognitive Psychology, 1980, 12, 97–136). This feature-integration theory predicts that when attention is diverted or overloaded, features may be wrongly recombined, giving rise to “illusory conjunctions.” The present paper confirms that illusory conjunctions are frequently experienced among unattended stimuli varying in color and shape, and that they occur also with size and solidity (outlined versus filled-in shapes). They are shown both in verbal recall and in simultaneous and successive matching tasks, making it unlikely that they depend on verbal labeling or on memory failure. They occur as often between stimuli differing on many features as between more similar stimuli, and spatial separation has little effect on their frequency. Each feature seems to be coded as an independent entity and to migrate, when attention is diverted, with few constraints from the other features of its source or destination.