Test of a distributional theory of intuitive numerical prediction

This paper investigates models that describe how subjects combine uncertain information to arrive at an intuitive prediction of a criterion. Subjects were trained, with feedback, to predict a numerical criterion from each of three single cues. Then they were asked to predict the criterion, without feedback, either from pairs of cues or from single cues. Their predictions were not consistent with a relative weight averaging model, since pairs of cues did not combine additively. Instead, the effect of a cue was inversely proportional to the standard deviation of the criterion at each level of the cue. Subjects appeared to apply greater weight to cue levels with smaller variance, i.e., those cue levels that were more valid. The data could be described by a distributional theory referred to as the equal probability model. For the present experiment, this model implies that the criterion means associated with the levels of each cue are weighted by the reciprocals of the standard deviations and then averaged. Relations between the equal probability model and other models of impression formation are discussed.     

A guide to family/school interventions for the family therapist

When presented with a behavioral problem or symptom expression that involves two systems, such as a serious school-related problem, the therapist needs to design an approach that will intervene effectively and expeditiously in both systems. This paper offers a guide to stages of problem escalation and therapeutic intervention that is intended to aid the problem-solver's thinking processes in approaching a troubled situation that involves two systems, the school and the home.     

Evidence for disparity change as the primary stimulus for stereoscopic processing

Subjects were able to respond to a lens-induced stereoscopic slant more quickly and more accurately when it was imposed on only part of a surface rather than on the whole surface. This shows that the presence of a stereoscopic boundary, where disparity is discontinuous, increases the efficiency of stereoscopic processing. This finding is not consistent with many current models of stereopsis.     

Non-Modality Specific Speech Coding: The Processing Of Lip-Read Information

Two experiments investigated the nature of the code in which lip-read speech is processed. In Experiment 1 subjects repeated words, presented with lip-read and masked auditory components out of synchrony by 600 ms. In one condition the lip-read input preceded the auditory input, and in the second condition the auditory input preceded the lip-read input. Direction of the modality lead did not affect the accuracy of report. Unlike auditory/graphic letter matching (Wood, 1974), the processing code used to match lip-read and auditory stimuli is insensitive to the temporal ordering of the input modalities. In Experiment 2, subjects were presented with two types of lists of colour names: in one list some words were heard, and some read; the other list consisted of heard and lip-read words. When asked to recall words from only one type of input presentation, subjects confused lip-read and heard words more frequently than they confused heard and read words. The results indicate that lip-read and heard speech share a common, non-modality specific, processing stage that excludes graphically presented phonological information.     

Effects of simulated stuttering on listener recall

In an investigation of the effects of simulated stuttering on listener recall, a presentation was varied on two factors: degree of stuttering (mild or severe) and information value of stuttered words (low or high). A control presentation featuring non-stuttered speech also was prepared. Five groups of 16 subjects were randomly assigned to, and participated in, one of the five listening conditions. Then they completed a 20-item recall test. A one-way analysis of variance revealed sognificant differences among the five conditions. Two-way analysis of variance disclosed no main effects. However, a significant interaction showed that recall was lowest in the severe stuttering-high information condition. The results are discussed in terms of attention to critical information.     

Explaining the Psychological Effects of Unemployment for Young People: The Importance of Specific Situational Factors

Evidence of the effects of duration of unemployment and gender upon the psychological response to unemployment is reviewed. It is suggested that many of the apparent contradictions in this evidence can be resolved by reference to situational factors which shape how stressful unemployment is for a particular individual. The study reported tested the effects of a stressful period of unemployment on the psychological well-being, self-esteem and life-satisfaction of young people. No sex differences in response to unemployment were found, and this is explained in terms of the similarity of their experiences. The relevance of these findings for counselling the unemployed is discussed.     

Spatial knowledge in a young blind child

A set of eight experiments demonstrate spatial knowledge in a 2-year-old congenitally blind child and sighted blindfolded controls. Once the blind child had traveled along specific paths between objects in a novel array, she was able to make spatial inferences, finding new routes between those objects (Experiment 1). She could also do so when the routes were between places in space, not occupied by objects (Experiment II). Deviations from precisely straight routes in Experiments I and II were not due to faulty inferences, but probably came from imprecise motor control, since the same deviations occured when inferences were not required—when the child moved to a place designated by a sound source (Experiment III). This child's performances could not be accounted for by artifactual explanations: sound cues, experimenter bias, and echolocation were ruled out (Experiments IV, V, VI). Further, sighted blindfolded controls performed at roughly the same level (Experiment VII). Finally, Experiment VIII shows that the blind child could access her spatial knowledge for use in a simple map-reading task. We conclude that the young blind child has a system of spatial knowledge, including abstract, amodal rules     

Trading relations in the perception of speech by 5-year-old children

Five-year-old children were tested for perceptual trading relations between a temporal cue (silence duration) and a spectral cue (F₁ onset frequency) for the “say-stay” distinction. Identification functions were obtained for two synthetic “say-stay” continua, each containing systematic variations in the amount of silence following the /s/ noise. In one continuum, the vocalic portion had a lower F₁ onset than in the other continuum. Children showed a smaller trading relation than has been found with adults. They did not differ from adults, however, in their perception of an “ay-day” continuum formed by varying F₁ onset frequency only. The results of a discrimination task in which the two acoustic cues were made to “cooperate” or “conflict” phonetically supported the notion of perceptual equivalence of the temporal and spectral cues along a single phonetic dimension. The results indicate that young children, like adults, perceptually integrate multiple cues to a speech contrast in a phonetically relevant manner, but that they may not give the same perceptual weights to the various cues as do adults.