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841.
Effective overall performance in judgment tasks generally involves both acquisition of information and integration of the information acquired. When information is costly the decision maker must balance acquisition costs against improved decisional accuracy, a complex balancing problem in which, laboratory evidence suggests, humans often do poorly. The three experiments reported here extend this earlier evidence to different task structures, subject pools, incentive systems, information volumes, decision aids, and kind of data sources. Though each of these factors was found to affect performance, the general finding was of persistent underpurchase (buying less information overall than is optimal) and mispurchase (buying poor sources when better sources are available at the same cost), with significant inflation of overall costs. It is proposed that unaided human judgment is unequal to the complexity of the cost/benefit trade-offs involved in acquiring costly information, and that formal decision analysis should be preferred whenever the stakes justify. 相似文献
842.
A. L. Bouhuys D. G. M. Beersma R. H. Van den Hoofdakker 《Journal of psychopathology and behavioral assessment》1987,9(1):13-33
A considerable percentage of depressed patients do not respond to antidepressive treatment. Early indicators of prognosis are needed. The aims of this study are to examine (a) whether the interpersonal behavior of patients and psychiatrist, as assessed by means of direct observation of behavior during a baseline clinical interview, might have predictive value with respect to therapeutic outcome and (b) which predictive potency measures of psychomotor activation, as assessed by less refined methods, such as global clinical judgment, might have. In the analysis used, speech-pause behavior was taken as the basic structure of the interaction. The relations of other behaviors such as looking and hand and head movement with this structure were determined. Evidence is presented that in a group of 31 depressives, improvement after a period of 10 weeks was related to observed behaviors during a baseline interview. The behaviors of the patients are interpreted as relational or nonrelational. The relational behaviors (i.e., looking yesnodding, gesturing) occur less in patients who will improve, whereas the nonrelational behaviors (i.e., intensive body touching, head movements) occur more in these patients. The nonrelational behaviors are presumed to be indicative of the state of arousal. The predictive potency of these variables could not be explained by their relationship with the baseline severity of depression, which in itself also predicted improvement. Moreover, global clinical assessment of psychomotor activation (i.e., retardation and agitation) could not be related to outcome. 相似文献
843.
Homicide which occurs in intimate social relationships was studied using data from three Western Canadian cities. Variables which may be related to the relationship and homicide are also examined. Unstable relationships are clearly differentiated from other relationships and are more likely to result in homicide. Implications for future research are discussed. 相似文献
844.
Ann R. Eisenberg 《Argumentation》1987,1(2):113-125
The infant's first natural response when faced with opposition or when he opposes others' actions is to cry. As this kind of behavior becomes ineffective, the responses of the individuals with which he interacts force him to adopt more conventional — especially verbal — patterns of arguing, leading him to rational argumentation. The purpose of the present paper is to observe progressions in children's earliest verbal arguments and to see how and when they learn to adjust their strategies for different kinds of opponents (peers; parents; other adults). In order to examine the emergence of such persuasive strategies, and their distribution according to the different categories of opponents, systematic audiotape recordings of two Spanish-speaking girls between 2 and 3 years were analyzed. The data suggest that, although there were some differences in how the girls argued with parents versus peers, they were only beginning to adjust their speech to make it appropriate for one or the other type of listener. In general, they resorted to one dominant strategy for all listeners (insist, repeat, cry, scream, ...). Each girl, however, developed a small number of less frequently used strategies that she reserved for a subcategory of opponents. For example, one of them, Nancy, only threatened and insulted peers, while the other, Marisa, only used please and a temporizing strategy with parents. The girls used less adaptive, more agressive strategies (e.g. threats and insults) with their peers. With one exception, all of the girls' moves were self-centered. In fact, the girls had not yet reached the stage of rational argumentation. 相似文献
845.
One of the recent concerns in the study of eyewitness memory is how well lay knowledge, i.e. ‘common sense’, matches the findings of empirical research. A number of American and Canadian studies, some using questionnaire methodology, have found limitations in lay knowledge of eyewitness behaviour. Further studies have extended this general finding beyond the lay public–who are prospective jurors–to legal professionals such as lawyers and policemen. The present study utilized the Knowledge of Eyewitness Behaviour Questionnaire (KEBQ), an inventory used in previous studies, to replicate the North American studies with a British sample of students, including law students, and the general public. The results showed a great similarity between the North American and British samples' knowledge of eyewitness behaviour. A significant number of correct responses were made to eight of the 14 KEBQ items, with a significant number of incorrect responses to the remainder. It was also found that law students were no more knowledgeable than other subjects; that knowledge did not vary with age; and that previous experience as an eyewitness was not related to knowledge of eyewitness behaviour. In responding to some of the criticisms of questionnaire studies it is argued that the evidence is mounting in favour of the need for a recognized system to make jurors aware of the factors known to influence eyewitness testimony. 相似文献
846.
Three experiments tested the efficacy of the phonetic mnemonic system under varying conditions of application. The first study attempted unsuccessfully to replicate and extend the work of Morris and Greer (1984), who had shown training in the phonetic mnemonic method to facilitate memorization of a serial list of two-digit numbers. In the present study, subjects trained in the phonetic mnemonic method failed to learn lists of two-, four-, and six-digit numbers better than control subjects. The second experiment partially replicated the first, the differences being that training in the phonetic mnemonic method was strengthened, and time allotted for number recall was extended. Under these circumstances the phonetic mnemonic group recalled the two-, four-, and six-digit numbers significantly better than the control groups, a finding conforming with Morris and Greer's (1984) results. The third experiment partially replicated the second, everything being the same except that, in this case, subjects constructed their own key words representing each number, instead of these words being supplied by the experimenter. Under these conditions, subjects trained in the phonetic mnemonic method recalled significantly fewer numbers than control subjects. 相似文献
847.
Perceptual organization of acoustic stimuli by budgerigars (Melopsittacus undulatus): II. Vocal signals 总被引:1,自引:0,他引:1
R J Dooling T J Park S D Brown K Okanoya S D Soli 《Journal of comparative psychology (Washington, D.C. : 1983)》1987,101(4):367-381
Operant conditioning and multidimensional scaling procedures were used to study auditory perception of complex sounds in the budgerigar. In a same-different discrimination task, budgerigars learned to discriminate among natural vocal signals. Multidimensional scaling procedures were used to arrange these complex acoustic stimuli in a two-dimensional space reflecting perceptual organization. Results show that budgerigars group vocal stimuli according to functional and acoustical categories. Studies with only contact calls show that birds also make within-category discriminations. The acoustic cues in contact calls most salient to budgerigars appear to be quite complex. There is a suggestion that the sex of the signaler may also be encoded in these calls. The results from budgerigars were compared with the results from humans tested on some of the same sets of complex sounds. 相似文献
848.
D J Gubernick J R Alberts 《Journal of comparative psychology (Washington, D.C. : 1983)》1987,101(2):169-177
Most knowledge of parent-offspring relations in mammals is derived from studies of mother-infant interactions. Male parental care has been less well studied. We explored maternal and paternal behavior of the California mouse, Peromyscus californicus. Six pairs of parents and their young were videotaped continuously for 12 hours/day, on alternate days from Days 1 to 31 postpartum. Males exhibit all parental activities and to the same extent as displayed by mothers, except lactation. Male parental behavior begins on the day of birth. Mothers and fathers spend substantial and equivalent amounts of time in the nest and in physical contact with pups throughout lactation. Males devote more time than females to licking pups, although females engage in more pup anogenital licking. Mothers nurse for at least 4 weeks, and fathers and mothers both build nests and carry young. The biparental care system of Peromyscus californicus affords an opportunity to develop a broader, more complete view of parent-offspring relations. 相似文献
849.
We developed the Sheltered Care Environment Scale (SCES) to provide researchers and practitioners with a practical means of assessing the social climate in congregate residential settings for the elderly. The SCES, a 63-item yes/no questionnaire that can be completed by residents and staff members of a facility, taps their perceptions of seven dimensions of the social environment. These dimensions concern the quality of relationships, the personal growth orientation present in the facility, and maintenance and change of the social system. The SCES discriminates among settings, has moderate to high internal consistency and split-half reliability, and is sensitive to environmental change against a backdrop of relative stability over time. The SCES reflects actual, agreed-on qualities of a setting and is relatively unaffected by characteristics of the respondent. Normative data are available from a national sample of 244 facilities representing the variety of residential settings available to the elderly. 相似文献
850.
This study is an extension of previous observational work on the social ecology of dependence and independence in the institutionalized elderly. Observations of everyday, naturally occurring interactions between elderly residents of two different long-term institutions and their social partners were extended such that, aside from the identification of type of behavior, the dyadic form and continuity of each behavior was specified. The following were among the major results: (a) Previously found interaction patterns between elderly residents and their social partners, replicated in both a nursing home and a home for the chronically ill, supported the notion of discrepant social ecologies for dependent versus independent behaviors of residents: (b) specification of each behavioral act as to its dyadic form underscored the fact that the interactions were controlled largely by social partners and not by the elderly residents; (c) coding continuity or discontinuity of behavior suggested that independent behaviors were maintained by chaining; and (d) elderly residents in the home for the chronically ill evinced, as expected, more dependence-related behaviors. 相似文献