Conceptual combination with prototype concepts

This paper deals with how people combine simple, prototype concepts into complex ones; e.g., how people combine the prototypes for brown and apple so they can determine the typicality of objects in the conjunction brown apple. We first consider a proposal from fuzzy-set theory (Zadeh, 1965), namely, that the typicality of an object in a conjunction is equal to the minimum of that object's typicality in the constituents (e.g., an object's typicality as a brown apple cannot exceed its typicality as a brown or as an apple). We evaluated this “min rule” against the typicality ratings of naive subjects in two experiments. For each of numerous pictured objects, one group of subjects rated its typicality with respect to an adjective concept, a second group rated its typicality vis-à-vis a noun concept, and a third group rated its typicality with respect to the adjective-noun conjunction. In both studies, most objects were rated as more typical of the conjunction than of the noun. These findings violate not only the min rule but also other simple rules for relating typicality in a conjunction to typicalities in the constituents. As an alternative to seeking such rules, we argue for an approach to conceptual combination that starts with the prototype representations themselves. We illustrate one version of this approach in some detail, and show how it accounts for the major findings of the present experiments.     

Distortions in judged spatial relations

In three experiments, we explore distortions in subjects' judgments of relative geographical relations. People make large systematic errors in judging the geographical relations between two locations that are in different geographical or political units. There is a strong tendency to distort the judged relation to conform with the relation of the superordinate political unit. To account for this result, we present a model in which spatial information is stored hierarchically. Spatial relations between any two locations are stored explicitly only if those locations are within the same superordinate unit. Spatial relations not stored are inferred by combining the relations from between and within superordinate units.     

Long-term memory for a common object

A series of experiments was done to determine how completely and accurately people remember the visual details of a common object, a United States penny. People were asked to: draw a penny from unaided recall; draw a penny given a list of its visual features; choose from among a list of possible features those which do appear on a penny; indicate what was wrong with an erroneous drawing of a penny; and select the correct representation of a penny from among a set of incorrect drawings. Performance was surprisingly poor on all tasks. On balance, the results were consistent with the idea that the visual details of an object, even a very familiar object, are typically available from memory only to the extent that they are useful in everyday life. It was also suggested that recognition tasks may make much smaller demands on memory than is commonly assumed.     

Models of word recognition

Major hypotheses about the processes involved in word recognition are reviewed and then assessed through four experiments. The purpose of the first experiment was to examine some basic aspects of the processing of words, pseudowords, and nonwords, and beyond that, to discover basic differences in their processing that might underlie the word advantage. The second experiment was designed to assess the contribution of whole-word and letter cluster cues to the word advantage. Finally, Experiments III and IV were focused on the question of whether the word advantage can be wholly explained in terms of response bias or sophisticated guessing. Taken together, the results of these experiments were most compatible with criterion bias models. A version of the criterion bias model is suggested wherein the word advantage is attributed to interfacilitation among single letter and lexical units in memory.     

Logical competence and transitive inference in young children

Five-year-old children were trained on the length relationships between the adjacent members of a five-term series of sticks. They were then tested on their abilities (1) to judge the length relationships between nonadjacent pairs of the series, and (2) to incorporate an unseen novel stick into the series through inference. Children who were trained with sticks of markedly different lengths succeeded on the first test but not the second; they apparently relied on memory for the absolute lengths of the sticks. Children in the other groups succeeded on both tests. The critical factor in inducing the use of seriation and transitivity seemed to be the elimination of alternative solutions.     

Interacting plans

The paper explores certain phenomena which arise in stories, conversations, and human activity in general when the plans of two individuals are formed and carried out in an interactive situation. A notation system for representing interacting plans is introduced and applied in the analysis of a small portion of “Hansel and Gretel.” The analysis illustrates how a single actor plan can be modified by the needs of cooperative interaction with others and how cooperative interactive episodes can be transformed and used deceptively by one party in achieving his or her own covert goals.     

Diagnostic models for procedural bugs in basic mathematical skills

A new diagnostic modeling system for automatically synthesizing a deep-structure model of a student's misconceptions or bugs in his basic mathematical skills provides a mechanism for explaining why a student is making a mistake as opposed to simply identifying the mistake. This report is divided into four sections: The first provides examples of the problems that must be handled by a diagnostic model. It then introduces procedural networks as a general framework for representing the knowledge underlying a skill. The challenge in designing this representation is to find one that facilitates the discovery of misconceptions or bugs existing in a particular student's encoding of this knowledge. The second section discusses some of the pedagogical issues that have emerged from the use of diagnostic models within an instructional system. This discussion is framed in the context of a computer-based tutoring/gaming system developed to teach students and student teachers how to diagnose bugs strategically as well as how to provide a better understanding of the underlying structure of arithmetic skills. The third section describes our uses of an executable network as a tool for automatically diagnosing student behavior, for automatically generating “diagnostic” tests, and for judging the diagnostic quality of a given exam. Included in this section is a discussion of the success of this system in diagnosing 1300 school students from a data base of 20.000 test items. The last section discusses future research directions.     

Structure-mapping: A theoretical framework for analogy

A theory of analogy must describe how the meaning of an analogy is derived from the meanings of its parts. In the structure-mapping theory, the interpretation rules are characterized as implicit rules for mapping knowledge about a base domain into a target domain. Two important features of the theory are (a) the rules depend only on syntactic properties of the knowledge representation, and not on the specific content of the domains; and (b) the theoretical framework allows analogies to be distinguished cleanly from literal similarity statements, applications of abstractions, and other kinds of comparisons. Two mapping principles are described: (a) Relations between objects, rather than attributes of objects, are mapped from base to target; and (b) The particular relations mapped are determined by systematicity, as defined by the existence of higher-order relations.     

Age changes in nonverbal decoding as a function of increasing amounts of information

A test of nonverbal decoding skill (the PONS test) was administered to 632 subjects of eight different age levels, ranging from third graders to adults (Ages 8–33 years). Females were more accurate than males, older subjects were more accurate than younger ones, and all samples tended to decode more successfully when more information was available. Three different analyses showed that the increase in accuracy with increasing amounts of information was more pronounced for the older than for the younger groups. This differential effectiveness in the utilization of available information was discussed in terms of processing capacity, effort, and strategies for sampling a diversity of cues.     

Hierarchical coding in speech timing

The analysis of syllable and pause durations in speech production can provide information about the properties of a speaker's grammatical code. The present study was conducted to reveal aspects of this code by analyzing syllable and pause durations in structurally ambiguous sentences. In Experiments 1–6, acoustical measurements were made for a key syllabic segment and a following pause for 10 or more speakers. Each of six structural ambiguities, previously unrelated, involved a grammatical relation between the constituent following the pause and one of two possible constituents preceding the pause. The results showed lengthening of the syllabic segments and pauses for the reading in which the constituent following the pause was hierarchically dominated by the higher of the two possible preceding constituents in a syntactic representation. The effects were also observed, to a lesser extent, when the structurally ambiguous sentences were embedded in disambiguating paragraph contexts (Experiment 7). The results show that a single hierarchical principle can provide a unified account of speech timing effects for a number of otherwise unrelated ambiguities. This principle is superior to a linear alternative and provides specific inferences about hierarchical relations among syntactic constituents in speech coding.     

Expectancy confirmed again: A computer investigation of expectancy theory

A computerized attempt to replicate Aronson and Carlsmith's test of expectancy theory was conducted. Generally, subjects performed consistent with their expectancy, although the effect of expectancy was strongly attentuated by an overall achievement orientation. The results contradict the hypotheses that experimenter bias, demand characteristics, or differential recall of performance mediate the effects of expectancy upon performance.     

Measuring the visual angle of the mind's eye

People in these experiments claimed to be able to imagine moving only a given distance toward some imaged object before it seemed to “overflow,” not remaining all visible at once in their mental images. In addition, the larger the imaged object, the further away it seemed at the point of overflow. Although the angle subtended by the imaged objects at the point of overflow did not vary systematically with the size of the object, it did vary with different stimuli and instructions. These disparities in the size of the angle estimated seemed partly due to differences in criterion of “overflow”: Images seem to fade off gradually toward the periphery and not to occur in a spatial medium with sharply defined edges. When subjects were given a relatively strict definition of “overflow,” similar estimates of the “visual angle of the mind's eye” were obtained with three distinct methods: (1) Asking subjects to estimate the apparent distance at which an imaged horizontal ruler began to overflow; (2) Measuring how much time subjects required to scan across each degree of an imaged line, and then inferring the maximal angle from the time required to scan an image of a longest nonoverflowing line; and, (3) Simply asking subjects to hold up their hands to indicate the subjective size of an image of the longest possible nonoverflowing line. Finally, the maximal subjective size of images seemed related to the scope of “focal” vision, and images tended to be constructed spontaneously at about the maximal size.     

Producing simple utterances: How far ahead do we plan?

The subjects were presented pictures depicting a man, woman, girl, or boy touching, kicking, greeting, or standing beside one of the others. The subjects, constrained to using only these names, produced utterances whose lengths and grammatical forms were prespecified. The latencies for subject-verb utterances (e.g., The man is greeting) were longer than for naming the actors (e.g., The man). However, the latencies for subject-verb utterances when the actor was already known were shorter than for naming the actions (e.g., Greeting). Together these results imply that some, but not all, verb selection is performed before subject-verb utterances are initiated. Three control experiments eliminated alternative interpretations. Finally, it was demonstrated that the same degree of advance planning occurs before the initiation of subject-verb-object utterances (e.g., The man is greeting the woman).     

The use of natural consequences and a make-up period to eliminate school phobic behavior: A case study

The school-phobic behavior of a seven-year-old male was modified through implementing a program characterized by maximum parental involvement, restructing of natural consequences, and the use of a make-up period. Full-time school attendance was achieved on the sixteenth day of the program. The advantages of using school personnel as monitors and not as disciplinarians of the school-phobic child's behavior are discussed.     

Children's scales of length and loudness: A developmental application of cross-modal matching

The cross-modal matching techniques that have produced scales of sensory magnitude for a variety of perceptual continua in adults were used to construct similar scales in children. Subjects were adults and children 4, 6, 8, and 12 years old. Their task was, first, to match the loudness of a 1000-Hz tone to various visual lengths, and, second, to match the length of a white tape to various loudnesses of the tone. Almost all subjects were able to perform the matching tasks; the average precision of older subjects (12 and Adult) was somewhat greater, but in each of the younger age groups a majority of subjects performed with a precision that equaled that of older subjects. The exponent of the power function that relates length and loudness does not change with age. The scale factor does change, in a way that suggests either that a given sound intensity seems softer, or, more probable, that a given length seems longer, to younger children. The success of cross-modal matching with subjects as young as 4 years means that it is possible to investigate not only single perceptual scales but also intermodal organization in young children.