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51.
Manuel Barrera Jr. Susan A. Li Laurie Chassin 《American journal of community psychology》1995,23(4):479-507
Investigated ethnicity and parental alcoholism as factors that might influence the stress vulnerability of adolescents. It
extended an initial cross-sectional study of this same sample by adding two annual assessments which allowed for additional
cross-sectional analyses and longitudinal tests. Hispanic and Caucasian adolescents (N=306 at Time 1) completed measures of their own life stress, family conflict, and alcohol use. Their parents reported on adolescents'
internalizing and externalizing symptoms. Cross-sectional analyses at Time 2, and prospective analyses involving Time 1 and
Time 2 measures were, for the most part, consistent with the original study's results. Caucasian adolescents and children
of alcoholic parents appeared to be more vulnerable to stress than Hispanic adolescents and children of nonalcoholic parents.
Family conflict was a partial explanation for this increased vulnerability.
This research was supported by National Institute on Drug Abuse Grant DA05227 to Laurie Chassin (pricipal investigator) and
Manuel Barrera, Jr. (coprincipal investigator). Susan Li was supported by an American Psychological Association Minority Fellowship
Award. Portions of this research were presented at the conference, “Resiliency in Families: Racial and Ethnic Minority Families
in America” that was held at the University of Wisconsin, May 31–June 2, 1994. 相似文献
52.
Manuel Carreiras Morton Ann Gernsbacher Victor Villa 《Psychonomic bulletin & review》1995,2(1):124-129
An advantage of first mention—that is, faster access to participants mentioned first in a sentence—has previously been demonstrated only in English. We report three experiments demonstrating that the advantage of first mention occurs also in Spanish sentences, regardless of whether the first-mentioned participants are syntactic subjects, and regardless, too, of whether they are proper names or inanimate objects. Because greater word-order flexibility is allowed in Spanish than in English (e.g., nonpassive object-verb-subject constructions exist in Spanish), these findings provide additional evidence that the advantage of first mention is a general cognitive phenomenon. 相似文献
53.
54.
Summary Two experiments investigated relative spatial coding in the Simon effect. It was hypothesized that relative spatial coding is carried out with reference to the position of the focus of visual attention. The spatial code for an imperative stimulus presented exactly at the position of focal attention should be neutral on the horizontal plane, and therefore no Simon effect should be observed. However, when the imperative stimulus is presented to the left or to the right of the current position of focal attention, the spatial code should not be neutral, thus producing a Simon effect. In both experiments, focal attention was manipulated either by a peripherally presented onset precue (Experiment 1) or by a centrally presented symbolic precue (Experiment 2). Results showed that the Simon effect was substantially reduced in both experiments when a valid precue preceded the imperative stimulus just in time to conclude refocusing of attention to the position of the imperative stimulus before it was presented. However, conditions with neutral precues yielded a normally sized Simon effect. In both experiments, the Simon effect decreased as the SOA grew when the precue was valid. At least for the Simon effect, the results can be interpreted as evidence that relative spatial coding is functionally related to the position of the focus of attention. 相似文献
55.
56.
Zellini (1979, Theorem 3.1) has shown how to decompose an arbitrary symmetric matrix of ordern ×n as a linear combination of 1/2n(n+1) fixed rank one matrices, thus constructing an explicit tensor basis for the set of symmetricn ×n matrices. Zellini's decomposition is based on properties of persymmetric matrices. In the present paper, a simplified tensor basis is given, by showing that a symmetric matrix can also be decomposed in terms of 1/2n(n+1) fixed binary matrices of rank one. The decomposition implies that ann ×n ×p array consisting ofp symmetricn ×n slabs has maximal rank 1/2n(n+1). Likewise, an unconstrained INDSCAL (symmetric CANDECOMP/PARAFAC) decomposition of such an array will yield a perfect fit in 1/2n(n+1) dimensions. When the fitting only pertains to the off-diagonal elements of the symmetric matrices, as is the case in a version of PARAFAC where communalities are involved, the maximal number of dimensions can be further reduced to 1/2n(n–1). However, when the saliences in INDSCAL are constrained to be nonnegative, the tensor basis result does not apply. In fact, it is shown that in this case the number of dimensions needed can be as large asp, the number of matrices analyzed. 相似文献
57.
Jos V. M. Welie 《Theoretical medicine and bioethics》1994,15(3):211-225
Increasingly, contemporary medical ethicists have become aware of the need to explicate a foundation for their various models of applied ethics. Many of these theories are inspired by the apparent incompatibility of patient autonomy and provider beneficence. The principle of patient autonomy derives its current primacy to a large extent from its legal origins. However, this principle seems at odds with the clinical reality. In the bioethical literature, the notion of authenticity has been proposed as an alternative foundational principle to autonomy. This article examines this proposal in reference to various existentialist philosophers (Heidegger, Sartre, Camus and Marcel). It is concluded that the principle of autonomy fails to do what it is commonly supposed to do: provide a criterion of distinction that can be invoked to settle moral controversies between patients and providers. The existentialist concept of authenticity is more promising in at least one crucial respect: It acknowledges that the essence of human life disappears from sight if life's temporal character is reduced to a series of present decisions and actions. This also implies that the very quest for a criterion that allows physicians to distinguish between sudden, unexpected decisions of their patients to be or not to be respected, without recourse to the patient's past or future, is erroneous. 相似文献
58.
Vilhjálmur Árnason 《Theoretical medicine and bioethics》1994,15(3):227-242
The purpose of this paper is to evaluate the significance of the existential notion of authenticity for medical ethics. This is done by analyzing authenticity and examining its implications for the patient-professional relationship and for ethical decision-making in medical situations. It is argued that while authenticity implies important demand for individual responsibility, which has therapeutic significance, it perpetuates ideas which are antithetical both to authentic interaction between patients and professionals and to fruitful deliberation of moral dilemmas. In order to counteract these consequences, an alternative idea of authenticity is introduced. According to this idea, authenticity is not regarded primarily as individual sovereignty, but as an ability to participate in a dialogue in which the subjectivity of both partners is respected. Such practice, based on mutual trust and responsibility, would enhance common decision-making and overcome the alienation between patients and professionals. 相似文献
59.
Marek Franěk Jiři Mates Tomáš Radil Karin Beck Ernst Pöppel 《Attention, perception & psychophysics》1994,55(2):204-217
Musically trained and untrained subjects (N=30) were asked to synchronize their finger tapping with stimuli in auditory patterns. Each pattern comprised six successive tonal stimuli of the same duration, the first of which was accented by a different frequency. The duration of interstimulus onset intervals (ISIs) gradually increased or decreased in constant steps toward the end of the patterns. Four values of such steps were used in different trials: 20, 30, 45, and 60 msec. Various time-control mechanisms are hypothesized as being simultaneously responsible for subjects’ incorrect reproduction of the internal temporal ratios of the stimulus patterns. The mechanism of assimilation (of a central tendency) led subjects to enforce a regular (isochronous) structure on the patterns. The influence of other time-control mechanisms (distinction, subjective expression of an accent, sequential transfer) was expressed mainly in differences between intertap onset intervals (ITIs) and the corresponding ISIs at the beginning of the patterns. The duration of the first two ITIs was in the majority of the trials in an inverse ratio to the ratio of the respective ISIs. The distortions resulting from the timing mechanisms concerned were more pronounced in the performance of nonmusicians than in that of musicians. 相似文献
60.
Decompositions and biplots in three-way correspondence analysis 总被引:1,自引:0,他引:1
In this paper correspondence analysis for three-way contingency tables is presented using three-way generalisations of the singular value decomposition. It is shown that in combination with Lancaster's (1951) additive decomposition of interactions in three-way tables, a detailed analysis is possible of the deviations from independence. Finally, biplots are shown to produce powerful graphical representations of the results from three-way correspondence analyses. An example from child development is used to illustrate the theoretical developments. 相似文献