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31.
A simple procedure by which a speech signal may be switched on or off (or from one ear to the other) at a precise instant of time is described. The speech sample is first recorded on a magnetic tape loop. A reference pulse is then recorded preceding the speech signal. This reference pulse triggers an adjustable time delay which in tum operates an electronic switch at an appropriate time.  相似文献   
32.
Subjects had to make a “remove” or “do not remove” life-sustaining measures decision in three right to die cases where the patients differed in competence; for half the subjects, a living will was present in all the cases, whereas, for the other half, it was not. Subjects also gave their determinative reasons for their decisions. Support for the right to die varied by case, but not by competency, or by the presence of a living will. The subjects' reasons were highly predictive of their decisions, and related to the way case-specific facts were construed, revealing a number of disparities between the way courts and citizens construe whether the patient's condition is “terminal,” “irreversible,” and “painful,” or not. Beyond construing facts differently, the results also revealed a disparity between evolving case law and the community's “common sense justice” over a fundamental belief: whether dying is seen as private matter, outside the bounds of State intervention, or not.  相似文献   
33.
In this paper, we applied the behavioral-economic concept of unit price to the study of reinforcer magnitude in an attempt to provide a consistent account of the effects of reinforcer magnitude on behavior. Recent research in the experimental analysis of behavior and in behavioral pharmacology suggests that reinforcer magnitude interacts with the schedule of reinforcement to determine response rate and total consumption. The utility of the unit-price concept thus stems from its ability to quantify this interaction as a cost-benefit ratio (i.e., unit price = characteristics of the schedule of reinforcement divided by magnitude of reinforcement). Research employing the unit-price concept has shown that as unit price increases, a positively decelerating function exists for consumption (i.e., a function with an increasingly negative slope, when plotted on log coordinates) and a bitonic function exists for response rate. Based on these findings, the present analysis applied the unit-price concept to those studies of reinforcer magnitude and drug self-administration that examined the effects of reinforcer magnitude on response rate using simple schedules of reinforcement (e.g., fixed-ratio schedule). This resulted in three findings: (a) Reinforcer-magnitude manipulations and schedule manipulations interact in a manner that can be quantified in terms of unit price as benefit and cost factors, respectively; (b) different reinforcer-magnitude manipulations are functionally interchangeable as benefit factors in the unit-price ratio; and (c) these conclusions appear warranted despite the differences in reinforcers (food or drug), species (dogs, monkeys, or rats), and schedules (interval or ratio), and despite the fact that these studies were not designed for a unit-price analysis. In methodological terms, these results provide further evidence that employing the unit-price concept is a parsimonious method for examining the effects of reinforcer magnitude. In theoretical terms, these results suggest that a single process may underlie the effect of combined reinforcer-magnitude and schedule manipulations.  相似文献   
34.
Scholars have acknowledged the need to anchor scientific knowledge about social and psychological processes in the norms, values, and experiences of the partticular population under study. This article describes how focus groups can be incorporated into the planning stages of a research pogram to facilitate these goals. After a brief overview of teh central components of focus group research, and example from a program of research involving dual-earner African American families is used to as an illustration. The article describes how (a) the identification of cultural knowledge and (b)access to the language participants use to think and talk about a topic can help researchers formulate a conceptual framework, identify important constructs, and develop appropriate instruments for assessing constructs. Some strengths and limitations of focus group research are discussed.  相似文献   
35.
Transmodal perceptual learning was examined in a canonical same/different paradigm. Subjects naive to vibrotactile stimulation and unfamiliar with the task were asked to discriminate sequentially presented shapes moving laterally across an aperture. On all trials, the shapes were presented either visually and then vibrotactually or in the opposite modality order, and on all trials the shapes moved in opposite directions. Analyses of the data revealed that although perceptual learning was evident in both groups, the rate of the learning was more rapid in the visual-vibrotactile group. This interaction of modality order and practice was significant and was considered in terms of E.J. Gibson's theory of perceptual learning and in terms of the constructs, suggested by J.J. Gibson, of available and accessible information-in-stimulation and the education of attention.  相似文献   
36.
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
37.
This study examined the processing of supportive interactions by dysphoric and nondysphoric preteens and early adolescents. Seventy-two youngsters between the ages of 10 and 13 evaluated the supportiveness and helpfulness of standardized, videotaped interactions between a distressed preadolescent and a maternal figure. The tape presentations varied in terms of the level of depicted maternal support and instructional condition (degree of self-reference). The results indicated that dysphoric youngsters evaluated both the supportiveness and helpfulness of interactions less positively than nondysphoric agemates. Group differences in support evaluations were most pronounced in the self-referenced condition. The level of depicted support did not affect processing differences. Dysphoric subjects reported lower levels of emotional support in prior relationships and a greater tendency to view supportive behavior as ingenuine than nondysphoric peers. Variation in prior support experiences accounted for group differences in the evaluation of the supportiveness of new interactions.  相似文献   
38.
39.
How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
40.
Research has indicated that sexual assault on college campuses is pervasive (Koss, Gidycz, & Wisniewski, 1987) and that a history of sexual victimization serves as a risk factor for future victimization (Gidycz, Coble, Latham, & Layman, 1993). The purpose of the present investigation was to extend the findings of Gidycz et al. (1993) in examining the link among sexual victimization experiences. College women were evaluated for child and adolescent sexual victimization, family adjustment, alcohol use, psychological adjustment, interpersonal functioning, and sexual behavior. Women were reevaluated at 3, 5–6, and 9 months for adult victimization, psychological adjustment, interpersonal functioning, and sexual behavior. Loglinear analysis indicated that chances of being victimized in one time period increased with greater severity of victimization in the preceding time period. The path analysis assessing the mediating effects of these variables on victimization experiences was partially supported. Implications for future research and preventative efforts are discussed.  相似文献   
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