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51.
Hierarchical classes: Model and data analysis 总被引:1,自引:0,他引:1
A discrete, categorical model and a corresponding data-analysis method are presented for two-way two-mode (objects × attributes) data arrays with 0, 1 entries. The model contains the following two basic components: a set-theoretical formulation of the relations among objects and attributes; a Boolean decomposition of the matrix. The set-theoretical formulation defines a subset of the possible decompositions as consistent with it. A general method for graphically representing the set-theoretical decomposition is described. The data-analysis algorithm, dubbed HICLAS, aims at recovering the underlying structure in a data matrix by minimizing the discrepancies between the data and the recovered structure. HICLAS is evaluated with a simulation study and two empirical applications.This research was supported in part by a grant from the Belgian NSF (NFWO) to Paul De Boeck and in part by NSF Grant BNS-83-01027 to Seymour Rosenberg. We thank Iven Van Mechelen for clarifying several aspects of the Boolean algebraic formulation of the model and Phipps Arabie for his comments on an earlier draft. 相似文献
52.
Michael Gibertini Paul D. Retzlaff 《Journal of psychopathology and behavioral assessment》1988,10(1):65-74
Several factor analyses of the Millon Clinical Multiaxial Inventory (MCMI) have resulted in very similar solutions. Interpretation of this consistency is hampered by the fact that the 20 scales of the inventory share items. Overlapping items cause the scales to be linearly dependent and may create structure in the interscale correlation matrix which is separate from the subject response patterns. A factor analysis was performed on the matrix of item-overlap coefficients which describes the underlying artifactual structure of the instrument. Data from two new subject samples were factor analyzed and compared to previously published studies. Similarity coefficients among factors across studies were calculated. 相似文献
53.
David P. Farrington 《Behavioral sciences & the law》1988,6(3):307-331
Past research on delinquency and crime has provided convincing data about correlates but not about causes, because it has been largely cross-sectional in design. Whereas cross-sectional research focuses on variations between subjects, longitudinal research can provide information about changes within subjects, which are more important for causes, prevention, and treatment. Many of the most important results in criminology have been obtained in longitudinal or experimental studies, and the major studies of these types are reviewed here. It is now desirable to combine the two methods in a new coordinated program of longitudinal studies including experimental interventions or quasi-experimental analyses. Such projects could study several overlapping cohorts, extend from birth to adulthood, have frequent data collection, and obtain data from a variety of sources about many different types of antisocial behavior. 相似文献
54.
P. Paul Heppner Ann H. Baumgardner Lisa M. Larson Richard E. Petty 《Counselling psychology quarterly》1988,1(2-3):129-143
This study examined the usefulness of an 8-week applied problem-solving training program. Specifically, the study examined (a) whether problem-solving training that emphasised self-management principles would be useful, (b) if the effects of training would persist over time, (c) whether an individual difference variable (problem-solving appraisal) would affect training outcomes, and (d) whether the cognitive responses of the subjects during the course of training were related to their problem-solving appraisal or the change process. Results indicated that problem solving training was effective at enhancing students’ problem-solving appraisal, and that the self-report changes were maintained at a 1 year follow-up. In particular, training seemed most useful for students who initially appraised their problem solving very negatively. Finally, the results suggested that the process-oriented cognitive responses were related to students' initial problem-solving self-appraisal as well as the impact of training. Implications of the results are discussed in terms of counselling interventions, problem solving training, the interpersonal influence process, and future research. 相似文献
55.
David Bott 《Counselling psychology quarterly》1988,1(4):367-375
After outlining the predominant approaches which currently inform student counselling a case is made for adopting a developmental systemic paradigm, locating individual difficulties within the context of a family dilemma. The view is taken that family systems thinking and individual approaches can be complementary and that systemic work need not be restricted to formal family therapy and the technology this implies. 相似文献
56.
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
57.
This paper describes an amplifier for an electroencephalograph with gain of 1×104 to 1×106 and made entirely of commercially available IC components. The two-stage amplifier has a preamplifier stage with fixed gain of 1000, and a second stage with variable gain from 1 to 100. The final stage, an anti-aliasing filter, adds a gain of 10 to the signal. The circuit has high common mode rejection, low input bias current, very low noise characteristics, low offset voltages, and offset nulling capability built into the circuit. 相似文献
58.
Paul Draper 《International Journal for Philosophy of Religion》1992,32(3):149-165
I presented a substantially different version of this paper at the 1991 American Philosophical Association Central Division Meeting. William L. Rowe commented. The paper in its present form has profited considerably from Rowe's comments. 相似文献
59.
David Dooley Ralph Catalano Shiraz Mishra Seth Serxner 《Journal of applied social psychology》1992,22(6):451-470
We measured the relationship between earthquake concern and preparation in a community with high seismic risk. Five samples of approximately 800 people were interviewed by telephone about their earthquake concern, but this study focuses on the last two samples in which respondents reported their preparatory behaviors. The findings were consistent in showing greater likelihood of concern for those who had experienced an earthquake, were female, younger, and non-Anglo and a greater likelihood of preparation for those who had more concern, were married, and had lived longer at their present address. In a nonrecursive causal model, no evidence was found for a reciprocal effect of preparation on concern. These results were discussed in terms of health belief models including the self-efficacy and “stages of change” perspectives. Implications were drawn for interventions to increase preparation in ready-to-change groups and compensate for the resistance of those less willing or able to prepare. 相似文献
60.
Valerie A. Clarke Coral L. Ruffin David J. Hill Arthur L. Beamen 《Journal of applied social psychology》1992,22(8):638-656
Verbal expressions of probability are used in daily conversations, physician-physician and physician-patient communications, and questionnaire and interview responses. To assess the degree of agreement among English-speaking Australian adults in allocating numerical probabilities to these verbal expressions of probability, 966 interviewees provided estimates for 60 isolated expressions of probability and a sequence of seven items placed in a sequence. Means and median scores appeared to be consistent with common sense and with findings from other countries. Mirror-imaged terms were neither symmetrical nor equidistant, with the means and medians for the positive terms being closer to the mid-points of the scale than the means and medians of the negative terms. Items in a sequence of probability terms showed greater symmetry and less variability than isolated expressions. For most items, there was an unacceptably high level of within-subject and between-subject variability. Although subjects with higher levels of education and/ or mathematics education showed less variability, these factors accounted for very little of the variance. The greater variability in Australian results relative to those reported elsewhere was partly attributed to the use of interviews rather than questionnaires. There were no particular stems that yielded greater consistency. It was concluded that the use of these expressions leads to very imprecise communication. 相似文献