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991.
Michael Huberman 《Knowledge, Technology, and Policy》1994,7(4):13-33
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
992.
Michael Kubovy 《Psychonomic bulletin & review》1994,1(2):182-190
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
993.
Michael Domjan 《Psychonomic bulletin & review》1994,1(4):421-428
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
994.
Brick Johnstone Michael Pinkowski Janet Farmer Kristofer J. Hagglund 《Journal of clinical psychology in medical settings》1994,1(4):375-386
Outcome following traumatic brain injury (TBI) has been frequently evaluated for adults, although there has been minimal research on adolescents with TBI. It has been argued that TBI sequelae may be more difficult for adolescents to adjust to given developmental changes in physical (puberty), interpersonal (self-concept), and environmental domains (transition to college). In addition, it is commonly acknowledged that moderator variables such as psychiatric history, family functioning, substance use, and sexuality impact functional outcome following TBI, although it is often difficult to objectively evaluate these variables. The current study examined relationships among TBI-related deficits, moderator variables, and academic outcomes for six adolescents transitioning to college. The findings suggest that it may not be appropriate to predict functional outcome based solely on objective neuropsychological results. However, moderator variables appear to have a more direct relationship with outcome, depending on the moderator variable and the individual. 相似文献
995.
The use of facilitated communication with individuals with autism has generated considerable controversy over the past several years. Only recently has research begun appearing which examines the procedure using reasonable scientific controls to establish the validity of this form of communication. The present study assessed the validity of facilitated communication and evaluated the effects of facilitator influence with seven individuals with autism and mental retardation. Three individuals showed clear evidence of facilitator influence, another three showed no such influence, and one subject performed at chance levels. A follow-up session with the three subjects who showed no facilitator influence demonstrated that they also showed no unexpected language competence compared to their measured IQ and to assessment under standard conditions. Results are discussed in terms of significance for facilitated communication in general and in terms of the utility of the methodology as a means of demonstrating language competence or facilitator influence. 相似文献
996.
Two experiments investigated the role of short-term affective states on the way people perceive various aspects of their personal relationships. Using an unobtrusive mood induction in a field setting, Experiment 1 found significant mood congruency in evaluative judgments about well-established intimate relationships. Experiment 2 used a controlled laboratory procedure and found that evaluations of the relationship and the partner, as well as preferred styles of conflict resolution were all significantly affected by the respondents' transient mood state. Increasing relationship longevity did not reduce affective influences on judgments in either study. The results arc discussed in terms of the role of affective states in cognition and judgments, and the influence of affect on everyday judgments about personal relationships is considered. 相似文献
997.
Michael Borenstein 《Behavior research methods》1994,26(3):352-365
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
998.
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
999.
Tom C. A. Freeman Mike G. Harris P. A. Tyler 《Attention, perception & psychophysics》1994,55(6):689-699
Estimates of temporal proximity (sometimes called time-to-collision) from random-dot flow patterns are shown to be based upon retinal speed, rather than upon changes in dot density. Neither the spatial nor the temporal gradient of motion is essential to the task, but estimates can be made from either alone. Performance is unaffected by the addition of rotational motion, suggesting that observers axe capable of extracting the radial component of motion, which contains all the relevant information, from complex stimuli. 相似文献
1000.
Michael von Grunau Stéphane Dubé Cesar Galera 《Attention, perception & psychophysics》1994,55(5):575-592
Effects of the similarity between target and distractors in a visual search task were investigated in several experiments. Both familiar (numerals and letters) and unfamiliar (connected figures in a 5 × 5 matrix) stimuli were used. The observer had to report on the presence or absence of a target among a variable number of homogeneous distractors as fast and as accurately as possible. It was found that physical difference had the same clear effect on processing time far familiar and for unfamiliar stimuli: processing time decreased monotonically with increasing physical difference. Distractors unrelated to the target and those related to the target by a simple transformation (180° rotation, horizontal or vertical reflection) were also compared, while the physical difference was kept constant. For familiar stimuli, transformational relatedness increased processing time in comparison with that fort unrelated stimulus pairs. It was further shown in a scaling experiment that this effect could be accounted for by the amount of perceived similarity of the target-distractor pairs. For unfamiliar stimuli, transformational relatedness did have a smaller and less pronounced effect. Various comparable unrelated distractors resulted in a full range of processing times. Results from a similarity scaling experiment correlated well with the outcome of the experiments with unfamiliar stimuli. These results are interpreted in terms of an underlying continuum of perceived similarity as the basis of the speed of visual search, rather than a dichotomy of parallel versus serial processing. 相似文献