Perceiving motion and rigid structure from optic flow: A combined weak-perspective and polar-perspective approach

Structure-from-motion algorithms based on weak-perspective projection have many interesting properties and could serve as a basis for a model of human perception of motion and structure from motion (M&SFM). There is some psychophysical evidence, however, that points to discrepancies between what can be accomplished with these algorithms and the performance of human subjects in certain M&SFM tasks. In light of this evidence, this paper presents a mechanism that both takes advantage of all the possibilities offered by a weak-perspective approach and behaves in a manner that is in close correspondence with human performance in M&SFM tasks. It consists of a novel weak-perspective—based method operating at small visual angles and a complementary, perspective-projection—based method operating at larger visual angles.     

The effects of effort toward comprehension on recall

Four experiments examined free recall of generally incomprehensible sentences with appropriate cues that made the sentences comprehensible. A distinction is made between processes involved in an effort toward comprehension and elaboration processes that occur following comprehension. It was found that providing additional time for effort toward comprehension enhanced recall, while providing additional time for elaboration following comprehension did not enhance recall. It was also shown that the effects of effort toward comprehension were contingent upon eventual understanding of the sentence.     

TEACHING FOSTER GRANDPARENTS TO TRAIN SEVERELY HANDICAPPED PERSONS

Five foster grandparents were taught training skills for use in their daily interactions with severely handicapped persons in an institution. Following baseline, specific teaching procedures consisting of teacher instructions, prompts, modelling, and praise were implemented. The grandparents' frequency of training three skill areas increased as the specific teaching was implemented in multiple-baseline format. The total amount of training continued as teacher instructions, prompts, and modelling were terminated and praise continued, although the grandparents spent their training time emphasizing only two of the three skill areas. Teacher presence was gradually reduced over an 11-week period, with no decrease in grandparents' frequency of training. Four of the foster grandchildren, all profoundly retarded and multiply handicapped, demonstrated progress throughout the study. Results were discussed in light of the available contributions of foster grandparents in institutional settings and maintenance of staff training.     

The effect of serving as a model of self-control on subsequent resistance to deviation in children

The effect of having a child serve as a rule-following model for other children on the model's own subsequent rule-following was investigated in a resistance to deviation situation. First- and second-grade boys (age range 73 to 94 months) who were told they would serve as self-controlling models for others and who actually served in this capacity touched prohibited toys less than did boys who were not told they would serve as models. Boys told they were to serve as models but who were prevented from performing deviated at a level between the models and boys given no responsibility. Having children serve as rule-following models for others is suggested as an effective, non-punitive technique to increase their self-control.     

Decision Control and Process Control Effects on Procedural Fairness Judgments1

Process control, the capacity to influence the content of a conflict resolution hearing, has been found repeatedly to affect disputants' judgments of the fairness of conflict resolution procedures, but never has there been an unambiguous test of the effect in nonbinding procedures. It was hypothesized that disputants experiencing nonbinding conflict resolution procedures, as well as those experiencing binding conflict resolution, would judge as more fair procedures high in disputant process control. One hundred nineteen undergraduate males and females were placed in apparent conflict with other suhjects. The procedure used to resolve the conflict was either high or low in disputant process control and was either binding or nonbinding. The outcome of the conflict resolution procedure was either favorable or unfavordblc to the subject. High disputant process control procedures were judged more fair than low disputant process control procedures regardless of whether the decision was binding, confirming the hypothesis. The results support new applications of procedural fairness theory and research and encourage testing of process control-like variables in nonlegal settings.     

Perceived Control, Drive for Thinness, and Food Consumption: Anorexic Tendencies as Displaced Reactance

Although loss of perceived control has been implicated in the development of eating disorders, previous research has not directly tested the relationship between perceived control and food consumption. This study investigated the hypothesis that individuals with anorexic tendencies react to low perceived control by restricting food intake as a means of regaining a sense of control. Forty female undergraduates who scored either low or high on the Drive for Thinness Scale (Garner & Olmsted, 1984) were led to believe they would be participating in two separate studies. Perceived control was experimentally manipulated such that half of the subjects experienced low control and half experienced high control over a social situation. Under the guise of a second experiment, subjects tasted breakfast cereals and completed measures relevant to eating and body image. Results showed that subjects who were high in drive for thinness (DT) who experienced low control ate less sweetened cereal and planned to eat less at dinner than high DT subjects who experienced high control. Low DT subjects were unaffected by the control manipulation. The results are discussed in terms of displaced reactance.     

Parent and child causal attributions during clinical interviews

Attributions made by children and their parents for the cause of the child's clinical problem were monitored during assessment interviews. Results support previously observed differences obtained through questionnaires, with parents making more attributions than their children to characteristics of the child. This pattern was affected by variations in interview format. Parents and children differed in the locus of their attributions when interviewed individually, but these differences were not present when families were interviewed with both parents and children present. Implications for the methodology of attribution research with child-clinical populations are highlighted.     

The “false consensus effect”: An egocentric bias in social perception and attribution processes

Evidence from four studies demonstrates that social observers tend to perceive a “false consensus” with respect to the relative commonness of their own responses. A related bias was shown to exist in the observers' social inferences. Thus, raters estimated particular responses to be relatively common and relatively unrevealing concerning the actors' distinguishing personal dispositions when the responses in question were similar to the raters' own responses; responses differing from those of the rater, by contrast, were perceived to be relatively uncommon and revealing of the actor. These results were obtained both in questionnaire studies presenting subjects with hypothetical situations and choices and in authentic conflict situations. The implications of these findings for our understanding of social perception phenomena and for our analysis of the divergent perceptions of actors and observers are discussed. Finally, cognitive and perceptual mechanisms are proposed which might account for distortions in perceived consensus and for corresponding biases in social inference and attributional processes.