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211.
The purpose of the present study was to investigate the relationship between brand names and consumers' perceived risk. Hypotheses dealt with whether the presence of a product's brand name affects consumers' perceived risk towards shopping online; whether the familiarity with a brand name influences consumers' perceived risk; and whether online shoppers and non‐shoppers perceive risk towards shopping online differently. Results indicate that the presence or absence of a product's brand name affects online shoppers' perceived risk, but in the opposite direction to that expected. There was no significant difference between online shoppers' perceived risk vis‐à‐vis brand familiarity; however, online shoppers possessed lower perceived risk than non‐shoppers. Implications and limitations are discussed and recommendations for future research are provided. Copyright © 2004 Henry Stewart Publications Ltd.  相似文献   
212.
Adolescence is a high-risk period for body image disturbance and appearance concerns. In a cascade model, we examined interrelations of body dysmorphic symptoms (BDS) with appearance rejection sensitivity (ARS) and tested gender moderation. Participants were 397 Australian adolescents (T1 Mage = 11.7, SD = 0.91; 56% girls) who completed six surveys over 4 years. In a random-intercept cross-lag model, two (of five possible) paths showed ARS predicted higher subsequent BDS, and three (of five possible) paths showed BDS predicted higher subsequent ARS. Girls reported more BDS and ARS than boys, and random intercepts of BDS and ARS were correlated with the correlation stronger in girls than boys. Cross-lag BDD-ARS associations over the six waves were not significantly moderated by gender. Overall, girls are at higher risk of appearance concerns than boys, but BDD-ARS cascade effects do not differ between girls and boys.  相似文献   
213.
As a test of Wagner's (1981) theory of habituation, three experiments examined the effects of stimulus preexposure on electrodermal responding to the absence of a stimulus and on omission-produced dishabituation. The general procedure for all experiments consisted of a preexposure phase in which one stimulus (S1) was presented 20 times, followed by a pairing phase in which S1 was followed by a second event, S2. After a number of S1-S2 pairings, S2 was omitted for one trial and was then represented following S1 on the next trial. Electrodermal activity was measured in all experiments, and in Experiments 2 and 3, a measure of expectancy of S2 in the presence of S1 was also obtained to provide a putative index of S2 priming by S1. Experiments 1 (N=48) and 2 (N=72) employed 15 S1-S2 pairings prior to S2 omission. Significant omission responding and dishabituation to S2 were obtained in both experiments. However, omission effects were not influenced by preexposure presentations of S1. Experiment 3, on the other hand, demonstrated that omission responding and dishabituation were attenuated by 20 preexposures of S1 when only 4 S1-S2 pairings were employed. In addition, Experiments 2 and 3 revealed that although expectation of S2 developed as a function of S1-S2 pairings, it too was reduced by preexposure to S1. Only Experiment 3 provided preexposure effects that are consistent with Wagner's (1981) theory.  相似文献   
214.
Booth A  Duvall D 《Sex roles》1981,7(8):847-856
Using a sample of Toronto women, we reexamine the relationship between employment and fertility with the aim of clarifying whether employment status is negatively related to the birth rate only among certain categories of women as defined by sex roles. Especially noteworthy is the finding that employed wives who rate their performance as a spouse and mother as better than most have a birth rate which is as high as that for women who are not in the labor force.The authors are indebted to David Johnson, Susan Welch, and Lynn White of the University of Nebraska, and Gordon Irving of Carleton University for their comments on an earlier version of this article. The views expressed here are the authors' and not those of the Ministry of State for Urban Affairs, Government of Canada, which provided funds to conduct the study of urban crowding from which the data reported here were drawn.  相似文献   
215.
Aggressive and sexual behaviour was studied in 5-min paired encounters between castrated prepubertal boars (N = 14) and normal (N = 2) or bulbectomized (N = 2) oestrogen-treated ovariectomized gilts. The boars were made sexually active by treatment with 17β-oestradiol + 5α-dihydrotestosterone. Half of the boars were sprayed on the snout with a solution containing a mixture of the boar pheromones 3α-androstenol and 5α-androstenone immediately before testing, and the remainder were treated with the vehicle solution. Aggression was almost always initiated by the gilts, and neither bulbectomy nor pheromone treatment of the boars reduced its occurrence. The results suggest that the display of aggression by gilts towards boars of similar body size is unlikely to be suppressed by the steroidal pheromones present in boar saliva.  相似文献   
216.
The dual systems model of adolescent risk‐taking portrays the period as one characterized by a combination of heightened sensation seeking and still‐maturing self‐regulation, but most tests of this model have been conducted in the United States or Western Europe. In the present study, these propositions are tested in an international sample of more than 5000 individuals between ages 10 and 30 years from 11 countries in Africa, Asia, Europe and the Americas, using a multi‐method test battery that includes both self‐report and performance‐based measures of both constructs. Consistent with the dual systems model, sensation seeking increased between preadolescence and late adolescence, peaked at age 19, and declined thereafter, whereas self‐regulation increased steadily from preadolescence into young adulthood, reaching a plateau between ages 23 and 26. Although there were some variations in the magnitude of the observed age trends, the developmental patterns were largely similar across countries.  相似文献   
217.
Verb learning is difficult for children (Gentner, 1982 ), partially because children have a bias to associate a novel verb not only with the action it represents, but also with the object on which it is learned (Kersten & Smith, 2002 ). Here we investigate how well 4‐ and 5‐year‐old children (N = 48) generalize novel verbs for actions on objects after doing or seeing the action (e.g., twisting a knob on an object) or after doing or seeing a gesture for the action (e.g., twisting in the air near an object). We find not only that children generalize more effectively through gesture experience, but also that this ability to generalize persists after a 24‐hour delay.  相似文献   
218.
To harness the complexity of their high‐dimensional bodies during sensorimotor development, infants are guided by patterns of freezing and freeing of degrees of freedom. For instance, when learning to reach, infants free the degrees of freedom in their arm proximodistally, that is, from joints that are closer to the body to those that are more distant. Here, we formulate and study computationally the hypothesis that such patterns can emerge spontaneously as the result of a family of stochastic optimization processes, without an innate encoding of a maturational schedule. In particular, we present simulated experiments with an arm where a computational learner progressively acquires reaching skills through adaptive exploration, and we show that a proximodistal organization appears spontaneously, which we denote PDFF (Proximo Distal Freezing and Freeing of degrees of freedom). We also compare this emergent organization between different arm morphologies—from human‐like to quite unnatural ones—to study the effect of different kinematic structures on the emergence of PDFF.  相似文献   
219.
Previous studies have shown that adults who stutter produce smaller corrective motor responses to compensate for unexpected auditory perturbations in comparison to adults who do not stutter, suggesting that stuttering may be associated with deficits in integration of auditory feedback for online speech monitoring. In this study, we examined whether stuttering is also associated with deficiencies in integrating and using discrepancies between expected and received auditory feedback to adaptively update motor programs for accurate speech production. Using a sensorimotor adaptation paradigm, we measured adaptive speech responses to auditory formant frequency perturbations in adults and children who stutter and their matched nonstuttering controls. We found that the magnitude of the speech adaptive response for children who stutter did not differ from that of fluent children. However, the adaptation magnitude of adults who stutter in response to auditory perturbation was significantly smaller than the adaptation magnitude of adults who do not stutter. Together these results indicate that stuttering is associated with deficits in integrating discrepancies between predicted and received auditory feedback to calibrate the speech production system in adults but not children. This auditory‐motor integration deficit thus appears to be a compensatory effect that develops over years of stuttering.  相似文献   
220.
Developmental psychology plays a central role in shaping evidence‐based best practices for prelingually deaf children. The Auditory Scaffolding Hypothesis (Conway et al., 2009) asserts that a lack of auditory stimulation in deaf children leads to impoverished implicit sequence learning abilities, measured via an artificial grammar learning (AGL) task. However, prior research is confounded by a lack of both auditory and language input. The current study examines implicit learning in deaf children who were (Deaf native signers) or were not (oral cochlear implant users) exposed to language from birth, and in hearing children, using both AGL and Serial Reaction Time (SRT) tasks. Neither deaf nor hearing children across the three groups show evidence of implicit learning on the AGL task, but all three groups show robust implicit learning on the SRT task. These findings argue against the Auditory Scaffolding Hypothesis, and suggest that implicit sequence learning may be resilient to both auditory and language deprivation, within the tested limits. A video abstract of this article can be viewed at: https://youtu.be/EeqfQqlVHLI [Correction added on 07 August 2017, after first online publication: The video abstract link was added.]  相似文献   
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