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941.
942.
A computer-controlled system that detects spontaneous activity (locomotion and rearing) and diurnal activity rhythms in small animals is described. Automatic recording of subtotals during test periods provides data about habituation (nonassociative learning). The system is relatively inexpensive to construct. Fabricated from highly reliable circuit components, it provides replicable measures that enable comparisons between different experimental treatments to be made using parametric statistics.  相似文献   
943.
944.
This paper develops hypotheses about the implications of different types of decision for the utilization of different types of systematically produced information: data, research, and analysis. The engineering and enlightenment models found in the knowledge utilization literature prove inadequate for this purpose. We turn to three decision models—routine, incremental, and fundamental–and determine their implied demands for information. We also examine how information might be used in scanning procedures in anticipation of decision regime shifts. The results suggest that patterns of information should differ markedly in each decision context and indicate that there may be an inherent bias against the use of research in decision. Evert A. Lindquist, a doctoral candidate at the Graduate School of Public Policy, University of Calfornia at Berkeley, is completing a dissertation onPolicy Institutes in Canada: The Organization and Relevance of Public Inquiry and will join the faculty of the Department of Political Science at the University of Toronto this fall. Organizations, public policy, and the role of information in decision making are among his primary research interests.  相似文献   
945.
An emergent social science of knowledge applications, drawing on a substantial multidisciplinary literature published over the past twenty-five years, signals an inversion of typical scholarly reasoning about the knowledge-society nexus. Whereas most scholarly research thus far has concentrated on conditions believed to affect the production of scientific and professional knowledge, we pose a new problematic: What must we examine in order to comprehend and consciously shape applications of scientific and professional knowledge to the manifold problems facing contemporary societies? To date, approaches to this problematic have proceeded on the basis of four broadly accepted if abstract theses about the nature of contemporary knowledge systems: subjectivity, corrigibility, sociality, and complexity. Within the boundaries supplied by these commonly accepted theses are unresolved controversies expressed in competing visions of complexity, alternative perspectives of causation, rival images of progress, and conflicting criteria of application.  相似文献   
946.
A technical issue in auditory spatial attention research is how best to provide low-cost, accurate control of the frequency, duration, and location of acoustic signals. Three solutions to the problem are compared: use of the internal oscillator of the Apple lIe, use of a Mountain A/D+D/A card, and use of an external oscillator chip. The unique advantages and drawbacks of each system are discussed. All share some common problems of external speaker interface, timing control, and interface with the software. Hardware and software solutions implemented on the Apple-Psych system are discussed, along with data that demonstrate the precision control achieved with the system.  相似文献   
947.
In this paper, I discuss a number of issues concerning software selection in instructional laboratories. First, I describe several taxonomies of instructional software and argue that the most important dimension of instructional software is that it must be an efficient tool. Second, I discuss some elements of the context of the instructional lab, including sophistication of users. Third, I explore design features, especially those related to ease of learning to use packages. Several other issues are also considered, such as where to find software reviews.  相似文献   
948.
This article presents a simulation-based tutorial system for exploring parallel distributed processing (PDP) models of information processing. The system consists of software and an accompanying handbook. The intent of the package is to make the ideas underlying PDP accessible and to disseminate some of the main simulation programs that we have developed. This article presents excerpts from the handbook that describe the approach taken, the organization of the handbook, and the software that comes with it. An example is given that illustrates the approach we have taken to teaching PDP, which involves presentation of relevant mathematical background, together with tutorial exercises that make use of the simulation programs.  相似文献   
949.
This paper compares several software packages that allow users to create new computer-run experiments, but do not require that users be able to program. Three dimensions are considered: package requirements, ease of learning, and power and flexibility.  相似文献   
950.
Difficulties with the Microsoft BASIC function for generating random numbers (RND) are cited and new problems reported. Fixes are suggested that allow use of some of the speed of the original function and that produce greatly improved pseudorandom numbers. A published generator is combined with the RND function as a compromise solution.  相似文献   
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