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231.
Various complexities that arise in the application of legal and/or clinical criteria to the actual assessment of competence/capacity are discussed, and a particular way of understanding the nature of such criteria is recommended.  相似文献   
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233.
A technique is described for rapidly collecting responses in auditory-localization experiments. Subjects indicate the perceived direction of the sound by pointing at a 20-cm-diam spherical model. In Experiment 1, the subjects judged the direction of a broadband signal, which could originate from any of 239 directions ranging through 360° of azimuth and between ?45° and +90° of elevation. Using this technique, the subjects responded 2–8 times more rapidly than previous subjects who used either a verbal-reporting technique or a head-pointing technique. Localization judgments were as accurate as they had been with verbal reports, but were not as accurate as judgments collected using the head-pointing technique. In Experiment 2, the signal was turned off and the experimenter read the spherical coordinates of the signal location to the subjects. The subjects pointed to these coordinates more accurately than they had judged the direction of the sounds in Experiment 1, suggesting that the response technique had not been the limiting factor in that experiment. Circumstances relevant to the choice of response techniques for auditory-localization experiments are discussed.  相似文献   
234.
Studies that have found an association between unemployment and psychological depression often fail to establish the direction of causal influence. Analyses of Epidemiologic Catchment Area panel data revealed that of employed respondents not diagnosed with major depression at first interview, those who became unemployed had over twice the risk of increased depressive symptoms and of becoming clinically depressed as those who continued employed. Although the increase in symptoms was statistically significant, the effect on clinical depression was not, possibly because of the low power of the test. The reverse causal path from clinical depression at Time 1 to becoming unemployed by Time 2 was not supported. The unemployment rate in the respondent's community at time of interview was not related directly to psychological depression but appeared associated indirectly with depression via its impact on the risk of becoming unemployed. Implications for policy and further research were discussed. The research described in this paper was supported by Grant #5 RO1 AA08379-02 from the National Institute of Alcohol Abuse and Alcoholism. The authors appreciate the suggestions provided by members of the Consortium for Research Involving Stress Processes sponsored by the W. T. Grant Foundation and by two anonymous journal reviewers.  相似文献   
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As a field of study, “research utilization” is at a turning point. Despite an accumulation of replicable findings, robust constructs, even a “soft technology” for bridging the gap between theory and practice, we are still largely in the situation of the distance between social problems of, let us say, conflict or inequality and the ability of social science to provide credible, reliable and usable solutions. At the same time, the initial paradigms, suffering from hyperrationalism, have given way to more transactional ones, and have been shaken by the tenets of postmodernism. Shaken, but not undone, as “middle-level” constructs emerge, ones that appear to link the research community with a variety of professional communities in more meaningful and durable ways. Michael Huberman has been Visiting Professor of Education at Harvard University since 1991, where he teaches research methodologies and conducts research on knowledge dissemination. He is also Senior Research Associate at the Network, Inc.  相似文献   
237.
Bravais (1850/1949) demonstrated that there are five types of periodic dot patterns (or lattices): oblique, rectangular, centered rectangular, square, and hexagonal. Gestalt psychologists studied grouping by proximity in rectangular and square dot patterns. In the first part of the present paper, I (1) describe the geometry of the five types of lattices, and (2) explain why, for the study of perception, centered rectangular lattices must be divided into two classes (centered rectangular andrhombic). I also show how all lattices can be located in a two-dimensional space. In the second part of the paper, I show how the geometry of these lattices determines their grouping and their multistability. I introduce the notion ofdegree of instability and explain how to order lattices from most stable to least stable (hexagonal). In the third part of the paper, I explore the effect of replacing the dots in a lattice with less symmetric motifs, thus creating wallpaper patterns. When a dot pattern is turned into a wallpaper pattern, its perceptual organization can be altered radically, overcoming grouping by proximity. I conclude the paper with an introduction to the implications of motif selection and placement for the perception of the ensuing patterns.  相似文献   
238.
Empirical and conceptual developments that led to the formulation of a behavior system for the sexual conditioning of male Japanese quail are described. Initial efforts concentrated on conditioning with localized conditioned stimuli and on identifying behavioral indices of conditioning. Later, learning about species-typical cues and about contextual cues was also explored, and it became evident that different types of cues control different aspects of sexual behavior. The results were used to formulate a behavior system containing both response and stimulus dimensions. In this system, contextual cues and local cues are assumed to elicit only general search behavior unconditionally. In contrast, unconditioned responses to species-typical cues of a female quail include general search, focal search, and copulatory behavior. General search, focal search, and copulatory behavior can become conditioned to local cues. Conditioning can also modify focal search behavior elicited by species-typical cues and can result in various modulatory influences between different types of stimuli. The behavior system approach provides a framework for organizing the diverse sexual conditioning effects and suggests future directions for investigation.  相似文献   
239.
Demystification, eschewing roles that disempower others and enhancing accessibility to the tools of knowledge, are consistent with the aims of community and applied social psychology. Although a focus on psychological empowerment can be a distraction from the need for actual power, it can also enhance it. Psychologists who avoid victim blaming and individual causal attribution biases can contribute to the discourse about social change. This requires both a reinterpretation of the known facts, and a reframing of social analysis. Social scientists and professionals are today's theologians and priests. Our power lies in our legitimation as interpreters of social reality. Teaching the psychology of empowerment, participative decision making and informed consent can influence the powerful as well as the powerless.  相似文献   
240.
This paper describes a method for generating sample survival distributions from a hypothetical population, as would be required for running Monte Carlo simulations. The method is based on the concept of a quincunx. Cases are entered into a life table and allowed to drop out or die during each interval with probabilities that mirror the hypothetical population. By repeating this process many times and tracking the results, the researcher is able to study the sampling distribution of effect size indices and test statistics, and can generate empirical estimates of power and precision for planned studies. Unlike other methods that are commonly used for this purpose, the model proposed here allows the researcher to define a population in which the hazard rates and/or attrition rates vary substantially from one time point to the next, as may be the case in clinical trials or studies of processing times. The method requires less than 100 lines of code and runs some 10,000 simulations per hour on a microcomputer.  相似文献   
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