Out-of-bag Prediction Error: A Cross Validation Index for Generalized Structured Component Analysis

Cross validation is a useful way of comparing predictive generalizability of theoretically plausible a priori models in structural equation modeling (SEM). A number of overall or local cross validation indices have been proposed for existing factor-based and component-based approaches to SEM, including covariance structure analysis and partial least squares path modeling. However, there is no such cross validation index available for generalized structured component analysis (GSCA) which is another component-based approach. We thus propose a cross validation index for GSCA, called Out-of-bag Prediction Error (OPE), which estimates the expected prediction error of a model over replications of so-called in-bag and out-of-bag samples constructed through the implementation of the bootstrap method. The calculation of this index is well-suited to the estimation procedure of GSCA, which uses the bootstrap method to obtain the standard errors or confidence intervals of parameter estimates. We empirically evaluate the performance of the proposed index through the analyses of both simulated and real data.     

A Limited Information Estimator for Dynamic Factor Models

Structural equation modeling (SEM) is an increasingly popular method for examining multivariate time series data. As in cross-sectional data analysis, structural misspecification of time series models is inevitable, and further complicated by the fact that errors occur in both the time series and measurement components of the model. In this article, we introduce a new limited information estimator and local fit diagnostic for dynamic factor models within the SEM framework. We demonstrate the implementation of this estimator and examine its performance under both correct and incorrect model specifications via a small simulation study. The estimates from this estimator are compared to those from the most common system-wide estimators and are found to be more robust to the structural misspecifications considered.     

Decision making in the prisoner's dilemma game: The effect of exit on cooperation and social welfare

The prisoner's dilemma game is a mixed‐motive game that offers two players the simultaneous choice between a cooperative and a defective alternative. An often neglected aspect of such a binary‐choice game, however, is that in many real‐life encounters, people can choose not only to cooperate or defect, but they also have a third option: to exit the social dilemma. Although in the literature a consensus has emerged that the addition of an exit opportunity benefits cooperation, there is only scant research into its effect on social welfare. In order to allow a direct comparison of cooperation rates and welfare levels across binary‐choice and trinary‐choice games, in this study, we used a design in which the same participants played similar games with and without an exit option (i.e., a within‐subjects design), and this in a range of structural variations. The findings of our study indicated that the aggregated outcome of both players is generally lower in games with an exit option than in games without an exit option. Moreover, our results showed that the efficiency of the exit option strongly depends on the specific outcome structure of the game (in terms of its endowment size, (a)symmetry, and level of noncorrespondence). In the discussion, it is argued that the implementation of an exit option as a strategy to increase social welfare should be critically assessed.     

公平感对社会认知的影响:经济因素的调节作用

目的及方法:基于中国综合社会调查2010年数据,采用多层结构方程模型,探究中国民众公平感对社会认知的作用,及经济因素在其中的调节效应。研究结果:第一,公平感越高,则社会冲突感越低,外在政治效能感越高,越倾向于对社会不平等进行内部归因,即对于社会的整体认知更加积极; 第二,经济因素能调节公平感与社会不平等内归因的关系,具体而言,经济水平越低,则公平感对于社会不平等的内部归因正向预测作用越大。     

Modelling elderly patients’ perception of the community pharmacist image when providing professional services*

Professional pharmaceutical services may impact on patient’s health behaviour as well as influence on patients’ perceptions of the pharmacist image. The Health Belief Model predicts health-related behaviours using patients’ beliefs. However, health beliefs (HBs) could transcend beyond predicting health behaviour and may have an impact on the patients’ perceptions of the pharmacist image. This study objective was to develop and test a model that relates patients’ HBs to patient’s perception of the image of the pharmacist, and to assess if the provision of pharmacy services (Intervention group-IG) influences this perception compared to usual care (Control group). A qualitative study was undertaken and a questionnaire was created for the development of the model. The content, dimensions, validity and reliability of the questionnaire were pre-tested qualitatively and in a pilot mail survey. The reliability and validity of the proposed model were tested using Confirmatory Factor Analysis (CFA). Structural Equation Modelling (SEM) was used to explain relationships between dimensions of the final model and to analyse differences between groups. As a result, a final model was developed. CFA concluded that the model was valid and reliable (Goodness of Fit indices: x²(80) = 125.726, p = .001, RMSEA = .04, SRMR = .04, GFI = .997, NFI = .93, CFI = .974). SEM indicated that ‘Perceived benefits’ were significantly associated with ‘Perceived Pharmacist Image’ in the whole sample. Differences were found in the IG with also ‘Self-efficacy’ significantly influencing ‘Perceived pharmacist image’. A model of patients’ HBs related to their image of the pharmacist was developed and tested. When pharmacists deliver professional services, these services modify some patients’ HBs that in turn influence public perception of the pharmacist.     

Decomposing the relationship between cognitive functioning and self-referent memory beliefs in older adulthood: what’s memory got to do with it?

With advancing age, episodic memory performance shows marked declines along with concurrent reports of lower subjective memory beliefs. Given that normative age-related declines in episodic memory co-occur with declines in other cognitive domains, we examined the relationship between memory beliefs and multiple domains of cognitive functioning. Confirmatory bi-factor structural equation models were used to parse the shared and independent variance among factors representing episodic memory, psychomotor speed, and executive reasoning in one large cohort study (Senior Odyssey, N = 462), and replicated using another large cohort of healthy older adults (ACTIVE, N = 2802). Accounting for a general fluid cognitive functioning factor (comprised of the shared variance among measures of episodic memory, speed, and reasoning) attenuated the relationship between objective memory performance and subjective memory beliefs in both samples. Moreover, the general cognitive functioning factor was the strongest predictor of memory beliefs in both samples. These findings are consistent with the notion that dispositional memory beliefs may reflect perceptions of cognition more broadly. This may be one reason why memory beliefs have broad predictive validity for interventions that target fluid cognitive ability.     

Substance or System as Foundational Metaphor for a Contemporary Christian World View?

Natural scientists increasingly employ the notion of system, i.e. organized groups of individual entities in dynamic interrelation, as a controlling metaphor in their analysis of physical reality, thereby reflecting a new emphasis on ecology and a holistic approach to reality. A.N. Whitehead’s understanding of the reciprocal cause-and-effect relation between constituent actual entities and the governing structure of the “society” to which they belong provides philosophical grounding for this new methodology and removes the danger of regarding systems as completely deterministic rather than open-ended and self-organizing. Likewise, a systems-oriented approach to the Christian doctrines of the Trinity, the Incarnation and Eschatology clears up residual ambiguities in the traditional understanding of those same beliefs.     

绝对音高加工的认知神经机制

绝对音高(absolute pitch,AP)是一种比较罕见的音高加工能力,具有特殊的认知和神经机制。事件相关电位研究表明AP音乐家进行音高命名时,工作记忆参与较少但涉及多个认知策略。功能神经成像研究发现左侧额叶背侧后部和左侧颞叶平面对AP音乐家非常重要,而准AP音乐家(quasi-AP)的某些右侧脑区的参与则反映其增加的音高加工负荷和难度。结构神经成像研究发现AP音乐家具有特殊的灰质结构形态及白质连接。未来研究有待将AP能力进一步分为"具有相对音高能力"与"没有相对音高能力"两类并观察相应的认知神经机制,并通过影像基因组学来探索基因多态性对AP能力的影响,以及有必要观察以声调语言为母语的音乐家进行音高加工的神经机制。