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861.
862.
Recent studies have called for the abandonment of the relative-time-spent scale in task inventories. This recommendation is based on findings that the job profile created with the scale data is highly correlated with the profile created from a much simpler “Do you perform this task?” checklist. We examined this issue using 3 inventories and 42 jobs (N=2252). Profile correlations were computed on only the tasks actually performed by incumbents to avoid possibly inflated rs due to including irrelevant tasks. The specificity of task inventory items was proposed as an explanation for the high correlation between the two job profiles. Specificity of items was examined by looking at both the type (job duties versus tasks) and the amount (number of items in job profile and average number of items relevant to each job) of items used in the inventory. Correlations between time spent and checklist profiles were in the .80's and .90's regardless of the number of irrelevant tasks or the specificity of tasks. We agree with previous military research and conclude that the relative-time-spent scale has limited incremental utility beyond a dichotomous checklist.  相似文献   
863.
The goal of the research was to compare decisions under risk in a situation in which forecasters (F) communicate to decision makers (DM) either numerically (e.g., .70) or verbally (e.g., likely) about the chances that a binary event will occur. Following each forecast, the DM bid for a winning or losing lottery based on the event. In Experiment 1 Fs and DMs also provided numerical translations of each verbal forecast after the DMs' bid. In Experiment 2 the DMs provided membership functions over the [0, 1] interval for each phrase used by the Fs. The primary results were: (a) extreme similarity in the DM's bids and rates of bidding under the two modes of communication; (b) greater variability in bids to specific verbal than numerical forecasts; (c) a pattern of bids, in which DMs demonstrated risk seeking for gains and risk neutrality for losses; (d) DMs' numerical translations in Experiment 1 were closer to .50 than were those of Fs; and (e) phrases selected by Fs had high membership values to DMs for the probabilities the Fs were attempting to describe. Points (a), (b), (d), and (e) are consistent with the ν-μ model which assumes that the vague meaning of a probability phrase can be represented by a membership function over the [0, 1] interval, and that in reaching a decision the DM focuses on a range of probabilities with sufficiently high membership. Point (c) is speculatively attributed to social aspects of the dyadic situation, and requires further investigation.  相似文献   
864.
Critical Flicker Fusion Thresholds (CFFTs) were measured in 644 elderly people identified from community-based general practice records, and the relationship of CFFT with age was investigated. The CFFT was measured using the method of limits with mean scores for three ascending (flicker/fusion) and three descending (fusion/flicker) presentations being recorded. The difference between the ascending and descending means was found to be significantly correlated with age (r=−0.131,P<0.001) and may reflect a reduced sensitivity of the Central Nervous System to suprathreshold flicker with increasing age. The results suggest that CFFT measurement has an important role to play in gerontological research as an objective measure of cognitive aspects of the ageing process.  相似文献   
865.
A 2-choice, operant-conditioning-based classification procedure was developed in which vervet monkeys (Cercopithecus aethiops) categorized species-typical snake and eagle alarm calls recorded from individually identified free-ranging animals. After preliminary training with a pair of calls from a single animal, 2 vervets were tested with novel exemplars produced by a variety of callers. Experiment 1 combined testing with continued training in routine classification of 14 new calls. In Experiment 2, the subjects were tested with 48 novel calls in rapid succession. Human (Homo sapiens) control subjects participated in the first study without extended preliminary training. Monkey and human subjects both showed immediate transfer to classification of unfamiliar alarm calls, despite variations both in voice characteristics and reproduction quality.  相似文献   
866.
Patterns of manual preference and the extent to which preference provided a benefit in performance (movement time) were evaluated in 7 young adult capuchin monkeys (Cebus apella). Directions of preference were inconsistent within individual animals across home-cage activities, unimanual, and bimanual experimental tasks. Preferences were more strongly expressed in the experimental tasks than in the home cage. A left bias in the population for prehension, predicted by recent theories, was not evident in any setting. Movement time was moderately negatively correlated with degree of preference within experimental tasks. The benefit to performance conferred by lateral preference was not dependent on whether the right or left hand was preferred. Lateralization of prehension appears to be a flexible process in these monkeys, which can result in quickly realized benefits in some conditions.  相似文献   
867.
In a panel study, more than 200 older adults were interviewed before and after a severe flood in southeastern Kentucky in 1984. The issue in this study was whether older adult flood victims were differentially vulnerable to increases in psychological and physical symptoms on the basis of their age, sex, marital status, occupational status, education level, and preflood symptom levels. Flood exposure was related to increases in depressive, anxiety, and somatic symptoms at 18 months postflood. Within this older adult sample, men, those with lower occupational status, and persons aged 55-64 were at significantly greater risk for increases in psychological symptoms. Sociodemographic status did not moderate the impact of flood exposure on physical health. Implications for crisis-intervention services to older adult disaster victims are discussed.  相似文献   
868.
Humility training is conceptualized as an appropriate treatment for persons who occasionally describe themselves, but are most frequently described by others as overbearing, insensitive and deceitful. Procedures are outlined to identify unrecognized fears and improve interpersonal skills. Humility is presented as a counterpoint to assertiveness and aggression/anger control interventions.  相似文献   
869.
In this article the perspective shifts to the “upstream” end of the agricultural knowledge and information system (AKIS). Because knowledge policy and strategic decision-making are not the prerogative of the public sector, organizations such as cooperative unions and multinational companies are included. After considering the influence of the changing environment on the nature of the AKIS, the role of knowledge management and policy in the emerging knowledge and information market is examined. Special attention is given to public and private R&D. The article then looks where information technology (IT) fits in and what considerations determine strategic investment in IT projects and sustained services. Some of the European experiences with this strategic investment are evaluated.  相似文献   
870.
The parent-child relationship plays an important role in Boszormenyi-Nagy's contextual therapy. This article presents the results of four interview studies of the opinions of parents and children about their ethical relationship.The children in these studies were five-to-seven-year-olds, 10-to-12 year olds and 15-year-olds. In one study only the mothers were interviewed, in the other three both parents participated. In all 73 children, 62 mothers, and 43 fathers were interviewed. The majority of parents and children agreed with most aspects of Nagy's theory about the parent-child relation, but there were some notable exceptions. Very few shared Nagy's ideas about entitlement. The age of the child had a clear effect on the opinions of the children on the dimensions of trust/reliability, loyalty and shifting of the balance with age of the child and on the opinions of the parents on the dimensions of childrens' rights, parents' rights, and balance of fairness. The sex of the interviewee had some effect: Mothers and fathers differ on the dimension of parents' rights and adolescent girls and boys differ on the dimensions of childrens' rights and parents' duties.  相似文献   
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