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21.
Subjects (N= 28) performing a complex disjunctive concept-formation task on a microcomputer were given the opportunity to seek help following failure to correctly identify concepts. The proportion of those seeking help was significantly greater when the source of help was the computer itself (86%) rather than another person (36%). Consistent with past research, those who did not ask for help gave reasons other than the potential negative social consequences of doing so. Self-report data and a systematic test for the presence of experimenter-induced demand ruled out several possible sources of confounding. The results have implications for designers of time-sharing and networked computer systems.  相似文献   
22.
The individual deciding on a nuclear weapons production policy is faced with a dilemma in which a choice must be made to support one of several conflicting defense policies. In order to investigate the social-psychological variables that are related to armament policy decision making, a telephone survey was conducted in the City of St. Louis, Missouri. Adult subjects (N= 110) responded to questions concerned with cognitive, attitudinal, and emotional responses to nuclear arms. Participants were also asked to choose a weapons production policy for the United States under conditions of continued and decreased Soviet nuclear arms production. Results indicated that respondents decisions about nuclear weapons production were related to their support for deterrence, the availability of their nuclear-related images, their emotional response to nuclear war, their attributions of responsibility for the prevention of nuclear war, and their political party affiliation. Distinctions between antinuclear decision-makers and pronuclear decision-makers are discussed.  相似文献   
23.
The relative importance of genetic and environmental factors for neuroticism, extraversion, impulsivity, and monotony avoidance were estimated in a sample of 99 monozygotic and 229 dizygotic pairs of twins reared apart (TRA) and a matched sample of 160 monozygotic and 212 dizygotic pairs of twins reared together (TRT). The average age was 58.6 (SD = 13.6); 72% of the twins were 50 or older. Model-fitting analyses verified the importance of genetic factors for all four measures; from 23% to 45% of the total variation was attributable to genetic sources. There was considerable evidence that these factors were operating in a nonadditive manner for extraversion and impulsivity. Shared environment accounted for less than 10% of the variance; some evidence for selective placement was found for neuroticism.  相似文献   
24.
Traits and states are concepts that people use to both describe and understand themselves and others. We show that people view these concepts as prototype-based categories that have a graded internal structure and fuzzy boundaries and identify a set of attributes that define the prototypical cores of two categories: traits and states. Prototypical traits are stable, long-lasting, and internally caused. Prototypical states are temporary, brief, and caused by external circumstances. These prototypes are not defined by averages, as the family-resemblance principle would suggest, but by ideal (or extreme) attribute values. Like other ideal-based categories, traits and states serve particular goals. Trait concepts permit people to predict the present from the past; state concepts identify those behaviors that can be controlled by manipulating the situation. These two complementary schemas are part of the extensive theory of psychological causality that is implicit in language. Abstract social concepts differ from object categories in their category standards, the nature of their attributes, and the interrelations among those attributes.  相似文献   
25.
The nature of visually guided locomotion was examined in an experiment where subjects had to walk to targets under various conditions. Target distance was manipulated so that subjects had to (a) lengthen their paces in order to hit the target; (b) shorten their paces; (c) make no adjustments to their standard pace length at all. They did this under four visual conditions: (a) normal vision; (b) with vision restricted to a "snapshot" each time the foot that was to be placed on the target was on the ground; (c) with a snapshot each time the foot to be placed was in the swing phase; and (d) no vision after departure fro the target. The results show that the subjects succeed in reaching the target in most cases. However, the smoothness and fluidity of their movements vary significantly between conditions. Under normal vision or where visual snapshots are delivered when the pointing foot is on the ground, locomotion is smoothly regulated as the subjects approach the target. where snapshots are delivered when the pointing foot is in the swing phase, regulation becomes clumsy and ill coordinated. Where no vision is available at all during the approach, adjustments are made, but these are least coordinated of all. The results show that well-coordinated visual regulation does not require continuous visual guidance but depends on intermittent information being available at the appropriate times in the action sequence. Such timing is often more important than the total amount of information that is available for guidance.  相似文献   
26.
Developmental sequence, relative timing, center of gravity, and phase-plane analyses were used to study a minimum of 15 years of longitudinal, filmed data on the development of hopping in 7 children. The developmental sequences revealed common, qualitative changes in the movement of the children, although each child progressed through the changes at his/her own rate. The timing analyses showed that, in the advanced hop, the tightest limb relationships were found within the hopping leg, then between contralateral limbs of the same girdle, and then between legs and arms. Relative-timing calculations revealed (a) intralimb, timing invariances that were present in first attempts to perform the skill at age 3 and remained for 15 years across all developmental levels; (b) emergent, interlimb timings that gradually became invariant; and (c) intra- and interlimb timing showing gradual development over the 15 years. One invariant, the time between landing and deepest knee flexion, is also invariant in the walk and the run (Shapiro, Zernicke, Gregor, & Diestel, 1981). Phase plane analyses indicated that the timing of peak and zero velocities may be the coordinative constant accounting for a relative timing invariance between the two legs. Position of the body's center of gravity may explain the invariant relative time between landing and deepest knee flexion, or the explanation could lie in the "equation of constraint" regulating joint equilibrium points. The data suggest that modeling the developing hop as the evolving interaction of four vibratory systems would be promising.  相似文献   
27.
Previous research has demonstrated that mild negative emotional imagery and unpleasant sensory stimuli lead to greater electromyographic activity over the brow muscle region than mild positive imagery and stimuli, even in the absence of significant changes in visceral and general facial EMG activity. Previous research has not addressed whether electromyographic responses over the brow region are a sensitive and specific index of emotions, however, since a multiplicity of events lead to changes in brow activity. In this research, facial electromyographic and audiovisual recordings were obtained while individuals were interviewed about themselves. Afterwards, individuals were asked to describe what they had been thinking of during specific segments of the interview marked by distinctive electromyographic responses over the brow region in the context of ongoing but stable levels of activity elsewhere in the face. The results are interpreted in terms of a continuous flow hypothesis of affect-laden information processing.  相似文献   
28.
29.
The addition of job-related information regarding an applicant's leadership ability reduced bias against female applicants applying for a managerial position.  相似文献   
30.
Two experiments were conducted to investigate the perceptual primacy of dimensional and similarity relations in the stimulus classifications of younger and older subjects. In Experiment 1, 4- and 10-year-olds were given free classifications in which they could group stimuli according to overall similarity or identities in size, color, or orientation. Both age groups classified stimuli most frequently according to identities on separate dimensions. In Experiment 2, 4-year-olds and adults were given free classifications followed by rule-governed classifications which required them to group stimuli according to specific relations. In the free classifications, a majority of subjects in both age groups classified the stimuli most frequently according to identities on separate dimensions. In the rule-governed classifications, both age groups were more accurate when a single separate relation was required for solution than when overall similarity was required. These results support a differential-sensitivity view of perceptual development, which asserts that individuals at all ages primarily perceive and use separate relations.  相似文献   
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