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991.
In many areas of science, research questions imply the analysis of a set of coupled data blocks, with, for instance, each block being an experimental unit by variable matrix, and the variables being the same in all matrices. To obtain an overall picture of the mechanisms that play a role in the different data matrices, the information in these matrices needs to be integrated. This may be achieved by applying a data‐analytic strategy in which a global model is fitted to all data matrices simultaneously, as in some forms of simultaneous component analysis (SCA). Since such a strategy implies that all data entries, regardless the matrix they belong to, contribute equally to the analysis, it may obfuscate the overall picture of the mechanisms underlying the data when the different data matrices are subject to different amounts of noise. One way out is to downweight entries from noisy data matrices in favour of entries from less noisy matrices. Information regarding the amount of noise that is present in each matrix, however, is, in most cases, not available. To deal with these problems, in this paper a novel maximum‐likelihood‐based simultaneous component analysis method, referred to as MxLSCA, is proposed. Being a stochastic extension of SCA, in MxLSCA the amount of noise in each data matrix is estimated and entries from noisy data matrices are downweighted. Both in an extensive simulation study and in an application to data stemming from cross‐cultural emotion psychology, it is shown that the novel MxLSCA strategy outperforms the SCA strategy with respect to disclosing the mechanisms underlying the coupled data.  相似文献   
992.
Psychological trauma and prolonged stress may cause mental disorders such as posttraumatic stress disorder (PTSD). Pretrauma personality is an important determinant of posttraumatic adjustment. Specifically, trait neuroticism has been identified as a risk factor for PTSD. Additionally, the combination of high negative affectivity or neuroticism with marked social inhibition or introversion, also called Type D personality (Denollet, 2000), may compose a risk factor for PTSD. There is no research available that examined pretrauma Type D personality in relation to PTSD. The present study examined the predictive validity of the Type D personality construct in a sample of Dutch soldiers. Data were collected prior to and 6 months after military deployment to Afghanistan. Separate multiple regression analyses were performed to examine the predictive validity of Type D personality. First, Type D personality was defined as the interaction between negative affect and social inhibition (Na × Si). In a second analysis, Type D was defined following cutoff criteria recommended by Denollet (2000). Results showed that negative affectivity was a significant predictor of PTSD symptoms. Social inhibition and the interaction Na × Si did not add to the amount of explained variance in postdeployment PTSD scores over the effects of childhood abuse, negative affectivity, and prior psychological symptoms. A second analysis showed that Type D personality (dichotomous) did not add to the amount of explained variance in postdeployment PTSD scores over the effects of childhood abuse, and prior psychological symptoms. Therefore, Type D personality appears to be of limited value to explain development of combat-related PTSD symptoms.  相似文献   
993.
Huntington claimed that today's major conflicts are most likely to erupt between religiously defined “civilizations,” in particular between Christianity and Islam. Using World Values Surveys from 86 nations, we examine differences between Christians and Muslims in preferences for religious political leaders. The results suggest a marked difference between Muslims and Christians in their attitudes toward religious politicians, with Muslims more favorable by 20 points out of 100. Devoutness, education, degree of government corruption, and status as a formerly Communist state account for the difference. Little support is found for the clash‐of‐civilizations hypothesis. Instead, we find that a clash of individual beliefs—between the devout and the secular—along with enduring differences between the more developed and less developed world explains the difference between Islam and Christianity with regards to preferences for religious political leaders.  相似文献   
994.
Following a landmark component analysis of cognitive therapy by Jacobson and colleagues (1996), there has been renewed interest in behavioral activation (BA) treatments for depression. The Behavioral Activation for Depression Scale (BADS) was developed to measure when and how clients become activated over the course of BA treatment. Multiple studies have provided initial support for the BADS but have also identified several potential problems. Four studies were conducted in order to develop and provide initial evaluation of a short form of the BADS that addresses these concerns. In Study 1, an exploratory factor analysis was conducted on existing data using the original BADS in order to identify items to retain for the short form. In Study 2, these items were administered to a new sample of college students with elevated depressive symptoms and were analyzed with exploratory and confirmatory factor analyses. Study 3 examined the predictive validity of the BADS-SF by examining the BADS-SF and depression scores in relation to activity tracking and reward-value ratings over the course of 1 week. Study 4 examined BADS-SF data over the course of BA treatment for two clients using cross-lagged panel correlations. With one client, changes in BADS-SF scores led changes in depression scores by 1 week, whereas with the other client changes in BADS-SF and depression scores occurred concurrently. These studies resulted in a nine-item scale that demonstrated good item characteristics as well as acceptable internal consistency reliability, construct validity, and predictive validity.  相似文献   
995.
The presence of a best friend buffers the effects of negative experiences   总被引:1,自引:0,他引:1  
The goal of the current study was to examine how the presence of a best friend might serve as protection against the effect of negative experiences on global self-worth and the hypothalamic-pituitary-adrenocortical axis (HPA axis). A total of 103 English-speaking male (n = 55) and female (n = 48) participants from Grade 5 (M = 10.27 years) and Grade 6 (M = 11.30 years) completed booklets about their experiences that occurred 20 min previously and how they felt about themselves at the moment, and they provided saliva multiple times per day over the course of 4 consecutive days. Having a best friend present during an experience significantly buffered the effect of the negativity of the experience on cortisol and global self-worth. When a best friend was not present, there was a significant increase in cortisol and a significant decrease in global self-worth as the negativity of the experience increased. When a best friend was present, there was less change in cortisol and global self-worth due to the negativity of the experience.  相似文献   
996.
Researchers often have expectations about the research outcomes in regard to inequality constraints between, e.g., group means. Consider the example of researchers who investigated the effects of inducing a negative emotional state in aggressive boys. It was expected that highly aggressive boys would, on average, score higher on aggressive responses toward other peers than moderately aggressive boys, who would in turn score higher than nonaggressive boys. In most cases, null hypothesis testing is used to evaluate such hypotheses. We show, however, that hypotheses formulated using inequality constraints between the group means are generally not evaluated properly. The wrong hypotheses are tested, i.e.. the null hypothesis that group means are equal. In this article, we propose an innovative solution to these above-mentioned issues using Bayesian model selection, which we illustrate using a case study.  相似文献   
997.
Self-regulation of behavior frequently requires that people disengage from goals that are too difficult to attain. The current studies investigate whether self-focused rumination hinders the execution of this crucial self-regulatory competence. In study one, participants attempted to solve anagrams, some of which were unsolvable, and their predisposition to engage in self-focused rumination was assessed. The tendency to ruminate was associated with getting stuck in the attempt to solve unsolvable anagrams. In study two, ruminative thoughts were manipulated by asking participants to focus on their self, personality, and goals in life, a task frequently employed to induce rumination. Compared to participants undergoing a distraction induction, ruminating participants were more likely to get stuck trying to solve unsolvable anagrams. These results suggest that self-focused rumination hinders disengagement from unattainable goals.  相似文献   
998.
The information provided by parents is indispensable for the early identification of psychopathology; for this reason, developmentally appropriate, reliable, and valid questionnaires are needed to gather their information. This study was designed to examine the utility of the Infant Toddler Social Emotional Assessment (ITSEA), a parent‐report questionnaire covering a wide range of behavior and emotional problems and competencies, in preschoolers referred for child psychiatric evaluation. The fathers and mothers of 85 children (23.2% girls; age 15–57 months) with autism spectrum, externalizing, or internalizing disorders completed the ITSEA, the Child Behavior Checklist (CBCL/2–3 and 4–18 versions), and the child domain of the Parenting Stress Index (PSI). The ITSEA showed good interrater reliability between parents, and validity was supported by significant correlations with corresponding CBCl and PSI domains. Evidence supporting the validity of the ITSEA for psychopathology was mixed across scales, with good diagnostic accuracy at the level of the broader psychiatric syndromes being achieved by the combination of subscales within the Externalizing, Internalizing, and Competence domains. The value of the ITSEA lies in the ability to systematically evaluate a wide range of problem behaviors and competencies. The ITSEA may be useful to create profiles of children's functioning in preschoolers referred for psychiatric assessment.  相似文献   
999.
In this study, cross-cultural differences in cognitive test scores are hypothesized to depend on a test's cultural complexity (Cultural Complexity Hypothesis: CCH), here conceptualized as its content familiarity, rather than on its cognitive complexity (Spearman's Hypothesis: SH). The content familiarity of tests assessing short-term memory, attention, working memory, and figural and verbal fluid reasoning, was manipulated by constructing test versions with an item content derived from either Afrikaans or Tswana culture in South Africa. Both test versions were administered to children of both cultures. The sample consisted of 161 urban Afrikaans, 181 urban, and 159 rural Tswana children (Mage = 9.37 years). Children generally performed best on the test version that was designed for their own group, particularly on the cognitively and culturally complex working memory and figural fluid reasoning tests. This relation between content familiarity and cognitive test performance supports CCH and disconfirms SH.  相似文献   
1000.
Abnormalities in eye tracking are consistently observed in schizophrenia patients and their relatives and have been proposed as an endophenotype of the disease. The aim of this study was to investigate the performance of patients at Ultra High Risk (UHR) for developing psychosis on a task of smooth pursuit eye movement (SPEM). Forty-six UHR patients and twenty-eight age and education matched controls were assessed with a task of SPEM and psychiatric questionnaires. Our results showed that both the corrective and non-corrective saccadic rates during pursuit were higher in the UHR group. There were however no differences in smooth pursuit gain between the two groups. The saccadic rate was related to positive UHR symptoms. Our findings indicate that abnormalities in SPEM are already present in UHR patients, prior to a first psychotic episode. These abnormalities occur only in the saccadic system.  相似文献   
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