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91.
We consider multi‐set data consisting of observations, k = 1,…, K (e.g., subject scores), on J variables in K different samples. We introduce a factor model for the J × J covariance matrices , k = 1,…, K, where the common part is modelled by Parafac2 and the unique variances , k = 1,…, K, are diagonal. The Parafac2 model implies a common loadings matrix that is rescaled for each k, and a common factor correlation matrix. We estimate the unique variances by minimum rank factor analysis on for each k. The factors can be chosen orthogonal or oblique. We present a novel algorithm to estimate the Parafac2 part and demonstrate its performance in a simulation study. Also, we fit our model to a data set in the literature. Our model is easy to estimate and interpret. The unique variances, the factor correlation matrix and the communalities are guaranteed to be proper, and a percentage of explained common variance can be computed for each k. Also, the Parafac2 part is rotationally unique under mild conditions.  相似文献   
92.
Objective: The authors attempted to develop and validate a general distress index for a multidimensional psychological symptom/outcome measure used in over 300 college counseling centers with more than 100,000 cases annually: the Counseling Center Assessment of Psychological Symptoms (CCAPS). Method: Four models were compared for fit indices (n = 19,247): the existing first-order factor model (without a general factor), a second-order factor model, a bifactor model, and a single factor or “total score” model. In separate clinical and non-clinical samples, concurrent and divergent validity were examined using several well-established measures of psychological symptoms, as well as two-week test–retest and treatment utilization data. Results: Second-order and bifactor models which captured a single “distress” factor both exhibited good fit to the data relative to the baseline and “total score” model. Validity data indicated that factors adequately measured meaningful clinical onstructs. Conclusion: Both the bifactor and second-order models indicated the presence of a “distress index” comprised items across many of the CCAPS subscales. This distress scale has strong applicability for benchmarking the overall severity and complexity of patients at different centers, and can be used to help identify colleges and universities with areas of clinical strength, which can be studied to improve the field. Clinically, the distress index offers a parsimonious and efficient method for clinicians to monitor patients’ progress through treatment.  相似文献   
93.

This report presents results from a study of the dimensionality and longitudinal stability of some common self-reported somatic complaints in teenage girls. Data were supplied by the Swedish longitudinal research program “Individual Development and Adaptation”. At four age levels (age 10, 13, 15, and 16 years) a representative sample of approximately 500 girls filled out questionnaires on various adjustment problems, including some typical somatic complaints. A separate dimension of somatic complaints was identified at each age level through factor analysis of the questionnaire data. Correlational stability of somatic complaints was not high until middle adolescence. At this age fairly stable patterns of somatic complaints were also found at the individual level; different somatic complaints were not found to be interchangeable. The results support the interpretation of girls' somatic complaints as a single, meaningful dimension in late childhood and adolescence. This dimension may be hypothesized to constitute a psychological process, somatization, manifesting itself in fairly stable patterns at the individual level in middle adolescence.  相似文献   
94.
In distributional semantics models (DSMs) such as latent semantic analysis (LSA), words are represented as vectors in a high-dimensional vector space. This allows for computing word similarities as the cosine of the angle between two such vectors. In two experiments, we investigated whether LSA cosine similarities predict priming effects, in that higher cosine similarities are associated with shorter reaction times (RTs). Critically, we applied a pseudo-random procedure in generating the item material to ensure that we directly manipulated LSA cosines as an independent variable. We employed two lexical priming experiments with lexical decision tasks (LDTs). In Experiment 1 we presented participants with 200 different prime words, each paired with one unique target. We found a significant effect of cosine similarities on RTs. The same was true for Experiment 2, where we reversed the prime-target order (primes of Experiment 1 were targets in Experiment 2, and vice versa). The results of these experiments confirm that LSA cosine similarities can predict priming effects, supporting the view that they are psychologically relevant. The present study thereby provides evidence for qualifying LSA cosine similarities not only as a linguistic measure, but also as a cognitive similarity measure. However, it is also shown that other DSMs can outperform LSA as a predictor of priming effects.  相似文献   
95.
96.
This panel emerged from shared clinical concerns when working with adult patients whose presentation style was reminiscent of a disorganized (Type D) infant attachment pattern. Psychotherapeutic work with such patients poses complicated transference and countertransference dilemmas which are addressed by all four panellists via theory and clinical vignettes. In common is an interest in contemporary attachment, neuroscience and trauma theories and their relationship to analytical psychology. Intergenerational trauma seems to be a salient factor in the evolution of fragmented and fragmenting interactions that lead to failures in self-coherence and healthy interpersonal relationships. Such early relational trauma is compounded by further episodes of abuse and neglect leading to failure in a core sense of self. These clinicians share how they have integrated theory and practice in order to help dissociated and disorganized patients to transform their dark and extraordinary suffering through implicit and explicit experiences with the analyst into new, life giving patterns of relationship with self and others. The alchemy of transformation, both positive and negative, is evident in the case material presented.  相似文献   
97.
本文通过讲述血管内皮舒张因子(endothelium-derived relaxing factor,EDRF)发现过程中的一些事例,讨论科学研究中的偶然性与必然性之间的辩证关系。把握偶然性和必然性之间的对立统一关系,有助于深化对自然和社会规律的认识。科研工作者应运用辩证唯物主义的观点,重视偶然现象,探索必然规律。  相似文献   
98.
探讨血浆血管内皮生长因子(P-VEGF)在乳腺癌术后复发转移患者中的表达情况及临床意义。采用酶联免疫吸附试验检测50例术后复发转移性乳腺癌患者及20例乳腺良性疾病对照组的P-VEGF含量,同期采用微粒子化学发光法检测术后复发转移性乳腺癌患者血清CEA和CA15-3的表达情况,进行对比研究。结论认为转移肿瘤细胞可产生大量...  相似文献   
99.
Most models of response time (RT) in elementary cognitive tasks implicitly assume that the speed-accuracy trade-off is continuous: When payoffs or instructions gradually increase the level of speed stress, people are assumed to gradually sacrifice response accuracy in exchange for gradual increases in response speed. This trade-off presumably operates over the entire range from accurate but slow responding to fast but chance-level responding (i.e., guessing). In this article, we challenge the assumption of continuity and propose a phase transition model for RTs and accuracy. Analogous to the fast guess model (Ollman, 1966), our model postulates two modes of processing: a guess mode and a stimulus-controlled mode. From catastrophe theory, we derive two important predictions that allow us to test our model against the fast guess model and against the popular class of sequential sampling models. The first prediction--hysteresis in the transitions between guessing and stimulus-controlled behavior--was confirmed in an experiment that gradually changed the reward for speed versus accuracy. The second prediction--bimodal RT distributions--was confirmed in an experiment that required participants to respond in a way that is intermediate between guessing and accurate responding.  相似文献   
100.
该研究旨在探讨当前大学生学校适应性的结构维度并编制简明评定问卷,运用了探索性因素分析和验证性因素分析的方法。结果表明,我国大学生学校适应性的结构维度包括四个方面的内容,分别是学习能力适应、人际关系适应、学校政治适应、学校文化适应。研究结果还显示,大学生学校适应性评定问卷具有良好的信度和效度指标,问卷的α系数达到0.80,探索性因素分析中总方差解释量达到62.89%,验证性因素分析的各项指标均达到理想水平。  相似文献   
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