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21.
Interpretations regarding the effects of exogenous and endogenous variables on endogenous variables in linear structural equation systems depend upon the convergence of a matrix power series. Convergence depends upon the eigenvalues of the structural coefficient matrix. The test for convergence developed by Jöreskog and Sörbom is shown to be only sufficient, not necessary and sufficient.  相似文献   
22.
Analysis of the elements of attention: A neuropsychological approach   总被引:15,自引:0,他引:15  
A model for conceptualizing the components or elements of attention is presented. The model substitutes for the diffuse and global concept of attention a group of four processes and links them to a putative system of cerebral structures. Data in support of the model are presented; they are derived from neuropsychological test scores obtained from two samples, the first consisting of 203 adult neuropsychiatric patients and normal control subjects, and the second, an epidemiologically-based sample of 435 elementary school children. Principal components analyses of test scores from these two populations yielded similar results: a set of independent elements of attention that are assayed by different tests. This work presents a heuristic for clinical research in which the measurement of attention is essential.  相似文献   
23.
The definition and role of the expert witness is reviewed. Two conceptual systems for viewing the world, the scientific method and the adversarial system, are compared. The reconciliation and integration of these two discrepant systems are discussed in terms of input versus outcome. The rules of evidence, as well as problems of communication between the systems, are reviewed with the aim of providing expert witnesses with a better understanding of effective testimony. Finally, collaboration between the two systems is called for in order to provide guidelines for both neuropsychologists and attorneys.  相似文献   
24.
The life and times of PSI   总被引:1,自引:0,他引:1  
This paper describes the essential features of the personalized system of instruction (PSI). Results from outcome research examining the effectiveness of PSI-based courses relative to traditional methods provide unequivocal support for the superiority of PSI. Parametric studies, or component analyses, show that the mastery requirement, immediate performance feedback, and review units are the key features underlying high quality student performances in PSI courses. The use of student proctors as peer-tutors, optional lectures, and selfpacing do not, in and of themselves, appear to be vital to student success in PSI courses. Despite its superiority, PSI has not supplanted traditional methods as the dominant pedagogical system in higher education. Difficulties inherent in overcoming the inertia of the lecture within our established instructional system, the implications of PSI for that system, and the Zeitgeist that permeates educational reform are the major obstacles to widespread adoption of PSI.  相似文献   
25.
A study of clinical medical ethicists was conducted to determine the various philosophical positions they hold with respect to ethical decision making in medicine and their various positions' relationship to the subjective-objective controversy in value theory. The study consisted of analyzing and interpreting data gathered from questionnaires from 52 clinical medical ethicists at 28 major health care centers in the United States. The study revealed that most clinical medical ethicists tend to be objectivists in value theory, i.e., believe that value judgments are knowledge claims capable of being true or false and therefore expressions of moral requirements and normative imperatives emanating from an external value structure or moral order in the world. In addition, the study revealed that most clinical medical ethicists are consistent in the philosophical foundations of their ethical decision making, i.e., in decision making regarding values they tend not to hold beliefs which are incompatible with other beliefs they hold about values.  相似文献   
26.
In jurisdictions throughout the United States, thousands of sexual assault kits (SAKs; also known as a “rape kits”) have not been submitted by the police for forensic DNA testing. DNA evidence may be helpful to sexual assault investigations and prosecutions by identifying perpetrators, revealing serial offenders through DNA matches across cases, and exonerating those who have been wrongly accused. This paper describes a longitudinal action research project conducted in Detroit, Michigan after that city discovered approximately 11,000 untested sexual assault kits in a police department storage facility. We conducted a root cause analysis to examine individual, organizational, community, and societal factors that contributed to the development of the rape kit backlog in Detroit. Based on those findings, we implemented and evaluated structural changes to increase staffing, promote kit testing, and retrain police and prosecutors so that cases could be reopened for investigation and prosecution. As we conducted this work, we also studied how this action research project impacted the Detroit criminal justice system. Participating in this project changed stakeholders’ attitudes about the utility of research to address community problems, the usefulness of DNA evidence in sexual assault cases, and the impact of trauma on survivors. The results led to new protocols for SAK testing and police investigations, and new state legislation mandating SAK forensic DNA testing.  相似文献   
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价值观是人们区分好坏、善恶、美丑、损益、是非的信念系统,通常是充满情感的。价值观具有稳定性与可变性的特点。价值观的稳定性表现为:基本价值观具有跨时间的稳定性和跨情境的一致性; 特别是保护性价值观和人生价值观具有较强的稳定性。个人的发展、经历重大事件以及实验干预可导致价值观的改变,可变性主要表现为价值观的重要性发生变化。从我国的实际出发,探讨个人的核心价值观问题、以及价值观研究中国化、价值观研究对价值观教育的启示,乃是我们今后研究的关注点。  相似文献   
29.
Representing a world or a physical/social environment in an agent’s cognitive system is essential for creating human-like artificial intelligence. This study takes a story-centered approach to this issue. In this context, a story refers to an internal representation involving a narrative structure, which is assumed to be a common form of organizing past, present, future, and fictional events and situations. In the artificial intelligence field, a story or narrative is traditionally treated as a symbolic representation. However, a symbolic story representation is limited in its representational power to construct a rich world. For example, a symbolic story representation is unfit to handle the sensory/bodily dimension of a world. In search of a computational theory for narrative-based world representation, this study proposes the conceptual framework of a Cogmic Space for a comic strip-like representation of a world. In the proposed framework, a story is positioned as a mid-level representation, in which the conceptual and sensory/bodily dimensions of a world are unified. The events and their background situations that constitute a story are unified into a sequence of panels. Based on this structure, a representation (i.e., a story) and the represented environment are connected via an isomorphism of their temporal, spatial, and relational structures. Furthermore, the framework of a Cogmic Space is associated with the generative aspect of representations, which is conceptualized in terms of unconscious- and conscious-level processes/representations. Finally, a proof-of-concept implementation is presented to provide a concrete account of the proposed framework.  相似文献   
30.
Irrigation practices can be advanced by the aid of cognitive computing models. Repeated droughts, population expansion and the impact of global warming collectively impose rigorous restrictions over irrigation practices. Reference evapotranspiration (ET0) is a vital factor to predict the crop water requirements based on climate data. There are many techniques available for the prediction of ET0. An efficient ET0 prediction model plays an important role in irrigation system to increase water productivity. In the present study, a review has been carried out over cognitive computing models used for the estimation of ET0. Review exhibits that artificial neural network (ANN) approach outperforms support vector machine (SVM) and genetic programming (GP). Second order neural network (SONN) is the most promising approach among ANN models.  相似文献   
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