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821.
k-SAT is a fundamental constraint satisfaction problem. It involvesS(m), the satisfaction set of the conjunction of m clauses,each clause a disjunction of k literals. The problem has manytheoretical, algorithmic and practical aspects. When the clauses are chosen at random it is anticipated (butnot fully proven) that, as the density parameter m/n (n thenumber of variables) grows, the transition of S(m) to beingempty, is abrupt: It has a "sharp threshold", with probability1 o(1). In this article we replace the random ensemble analysis by apseudo-random one: Derive the decay rule for individual sequencesof clauses, subject to combinatorial conditions, which in turnhold with probability 1 o(1). This is carried out under the big relaxation that k is not constantbut k = log n , or even r log log n . Then the decay of S isslow, "near-perfect" (like a radioactive decay), which entailssharp thresholds for the transition-time of S below any givenlevel, down to S = . 相似文献
822.
Symptom patterns in children and adolescents with obsessive-compulsive disorder (OCD) 总被引:1,自引:0,他引:1
OBJECTIVE: Obsessive-compulsive disorder (OCD) defined at the diagnostic level encompasses divergent symptoms. The present study examines symptom patterns in OCD in children and adolescents in order to search for the presence of diagnostic heterogeneity. SUBJECTS AND METHODS: Two hundred and thirteen outpatients with primary OCD participated. The patients' and primary caretakers' responses on the Children's Yale-Brown Obsessive-Compulsive Scale were used to generate severity ratings for 61 OCD symptoms, and cluster analysed them. RESULTS: A five cluster solution was judged to be the most clinically and theoretically relevant model. The clusters were named: (1) "Mental Rituals, Touching & Ordering", (2) "Contamination & Cleaning", (3) "Superstitions", (4) "Obsessions/Checking & Confessing" and (5) "Somatic Concerns". The symptom patterns of the groups differed, and three groups were particularly homogeneous. In addition, there were differences in severity, number of symptoms and age. CONCLUSIONS: OCD in children and adolescents is a heterogeneous disorder and discrepancies vis-à-vis adult studies indicate that childhood OCD may have developmentally specific traits. The sub-groups obtained are likely to have implications for the assessment of OCD symptoms in children, their prognosis and outcome in treatment research. 相似文献
823.
This study examined open-ended responses from 295 college students to questions regarding how they define the construct of calling, how having a calling influences their career development, and the extent to which the term “calling” may apply to areas of life other than work. Results indicated that students perceived a calling as originating from guiding forces, co-occurring with unique fit and well-being, having altruistic features, and extending to multiple life roles. These results largely support recent conceptualizations of calling in the career development literature, and suggest themes to explore in counseling with clients who desire to approach work as a calling. 相似文献
824.
Kirsi LaPointe 《Journal of Vocational Behavior》2010,77(1):1-9
In contrast to traditional definitions of career identity as an individual construct, this article argues for a discursive approach to career identity as a narrative practice. Career identity is conceptualized as a practice of articulating, performing and negotiating identity positions in narrating career experiences. By using the concept of positioning, this approach situates identities within particular historic, cultural and interactional contexts via the discourses and master narratives that position identity. It also leaves space for individual agency and change via the reflexive capacity of the person to modify and negotiate the competing positions available. The methodological implications are considered, and illustrated with an empirical case analysis. The contribution of the proposed approach is in offering contextualized understandings of actual practices, resources and constraints of identity construction while also allowing for in-depth analyses of the particularities of identity work and possibilities for change in careers. 相似文献
825.
The present study provides a data-driven approach to identifying groups of schools based on the concentration of at-risk students the school serves. The percentage of English language learners, minority students, and students eligible for free or reduced priced lunch were used as indicators in a latent profile analysis of 569 schools. The goal of the present study was to determine whether school-level average student reading performance varied as a function of the groups identified in the latent profile analysis. To do so, groups extracted by the latent profile analysis were used as school-level predictors of growth in oral reading fluency, which was modeled at the within-student level of a three-level hierarchical growth curve model. Oral reading fluency was measured at four points during the year in a large cross-sectional sample of first-, second-, and third-grade students. Results indicated that schools were able to be classified into four distinct groups based on their concentrations and types of at-risk students. Further, in all three grades, there were significant differences between the four identified groups observed in average reading fluency scores at the beginning of the year, the end of the year, and growth during the year indicating that groups based on school-concentration of at-risk students were significantly related to average student achievement in reading ability. 相似文献
826.
Andreas Vrahimis 《British Journal for the History of Philosophy》2013,21(1):177-188
In his recent article, titled ‘Royaumont Revisited’, Overgaard challenges Dummett's view that one needs to go as far back as the late nineteenth century in order to discover examples of genuine dialogue between ‘analytic’ and ‘continental’ philosophy. Instead, Overgaard argues that in the 1958 Royaumont colloquium, generally judged as a failed attempt at communication between the two camps, one can find some elements which may be utilized towards re-establishing a dialogue between these two sides. Yet, emphasising this image of Royaumont as a kind of battleground between ‘analytic’ and ‘continental’ philosophy obscures the plurality of philosophical approaches involved. Royaumont was the meeting point of more than two philosophical traditions, as can be shown by the divergent interests of its participants. Thus, though the potential for rapprochement between Oxford ‘linguistic philosophy’ and a certain strand of phenomenological thought may indeed be found among the discussions that took place during the colloquium, one should keep in mind that such rapprochement took place in the context of a meeting between, among others: continental ‘analytics’, Anglophone non-‘analytics’, French historians of philosophy, ‘analytic’ opponents of Oxford philosophy, Franciscan phenomenologists, and Oxonians who called their work ‘phenomenology’. 相似文献
827.
Richard S. Balkin Javier Cavazos Jr. Arthur E. Hernandez Roberto Garcia Denise L. Dominguez Alexandra Valarezo 《Journal of Addictions & Offender Counseling》2013,34(1):30-39
Factor analyses were conducted on scores from the Reynolds Adolescent Adjustment Screening Inventory (RAASI; Reynolds, 2001 ) representing at‐risk Latino youth. The 4‐factor model of the RAASI did not exhibit a good fit. However, evidence of generalizability for Latino youth was noted. 相似文献
828.
Seventy-two first, second and third grade boys and girls were administered seriation problems involving different combinations of shape and color variation. Success rates and latency scores were influenced by shape variation, but not by color variation or grade level. The failure to obtain predicted interactions between the effects of grade level and stimulus variation was attributed to the clarity of the relevant stimulus dimension. 相似文献
829.
Stability in the measurement of personality is crucial to its construct and predictive validity. The personality differentiation by intelligence hypothesis suggests that intelligence may be a threat to the measurement of personality. This study builds on existing literature by applying multigroup confirmatory factor analytic measurement invariance techniques to the item-level responses of a commonly used personality inventory. In contrast to recently published findings, our results suggest that the measurement of personality is not equivalent across intelligence levels. Though these results have important implications for the use of personality in research and practice, we maintain that personality measures are still important predictors of key criteria. We discuss future research directions, and hope that the current study highlights the need to increase the sophistication of currently available measurement techniques, and will bring continued examination of the personality differentiation by intelligence hypothesis. 相似文献
830.
Jordana Waxman Ryan J. Van Lieshout Saroj Saigal Michael H. Boyle Louis A. Schmidt 《Personality and individual differences》2013
Extremely low birth weight survivors (ELBW; <1000 g) display a personality style characterized by cautiousness, shyness, and risk aversion in their 20s. We examined whether non-impaired ELBW survivors were still more cautious than their normal birth weight (NBW) peers at ages 30–35 and assessed the stability of this personality characteristic across approximately a decade in the oldest known cohort of ELBW survivors. Of the 154 participants tested at ages 22–26, 111 (i.e., 72%) of them returned approximately 10 years later [i.e., 69% (49/71) ELBW and 75% (62/83) NBW], and once again they completed the Eysenck Personality Questionnaire-Revised (EPQ-R). We created the same theoretically and empirically derived composite measure of cautiousness at each visit by summing the EPQ-R psychoticism scale (reverse scored) and the EPQ-R lie scale. We found that ELBW adults reported higher cautiousness than their NBW counterparts at ages 30–35. We also found that levels of cautiousness remained stable over approximately 10 years in both groups. Our findings suggest that individuals born at ELBW were more cautious than NBW peers and that this personality characteristic remained stable into their early 30s. The present study appears to be the first empirical demonstration of personality stability among adult ELBW survivors. 相似文献