*  Measuring Latinos' Perceptions of Depression: A Confirmatory Factor Analysis of the Illness Perception Questionnaire - Academic...
This study examined the psychometric properties of the Revised Illness Perception Questionnaire adapted for a clinical sample of low-income Latinos suffering from depression. Participants (N = 339) were recruited from public primary care centers. Their average age was 49.73 years and the majority was foreign born females of either Mexican or Central American descent. Confirmatory factor analysis was used to test the factor structure of this measure. Construct and discriminant validity and internal consistency were evaluated. After the elimination of three items because of low factor loadings (| .40) and the specification of seven error covariances, a revised model composed of 24 items had adequate goodness-of-fit indices and factor loadings, supporting construct validity. Each of the subscales reported satisfactory internal consistency. Intercorrelations between the 5 illness perception ...
*  "On Time-Varying Factor Models: Estimation and Testing" by Liangjun SU and Xia WANG
Conventional factor models assume that factor loadings are fixed over a long horizon of time, which appears overly restrictive and unrealistic in applications. In this paper, we introduce a time-varying factor model where factor loadings are allowed to change smoothly over time. We propose a local version of the principal component method to estimate the latent factors and time-varying factor loadings simultaneously. We establish the limiting distributions of the estimated factors and factor loadings in the standard large N and large T framework. We also propose a BIC-type information criterion to determine the number of factors, which can be used in models with either time-varying or time-invariant factor models. Based on the comparison between the estimates of the common components under the null hypothesis of no structural changes and ...
*  Organisationally relevant variables and Keyes's Mental Health Continuum Scale: an exploratory study
Keyes, 2007, p. 100). This group was, furthermore, characterised by the lowest level of perceived helplessness, the highest level of functional goals, the highest level of self-reported resilience and the highest level of intimacy. They generally functioned better than moderately mentally healthy adults, who, in turn, functioned better than purely languishing adults. A confirmatory factor analysis on the short form of Keyes's questionnaire by Keyes et al. (2008) supported the hypothesised two-continuum model of mental health and mental illness found in the USA in a Setswana-speaking South African sample. The study also replicated the three-factor structure of emotional, psychological and social well-being found in US samples. Confirmatory factor analyses by Robitschek and Keyes (2009) also supported the three-factor model in two samples of US college students. Mental illness, languishing and flourishing are not stable or ...
*  Frontiers | Evaluation of Mother-Child Agreement and Factorial Structures of the SCARED Questionnaire in an Italian Clinical...
BACKGROUND: A great part of the literature has confirmed the importance of both child and parents reports as source of factual information, especially for childhood emotional syndromes. In our study we aimed at: i) calculating mother-child agreement and ii) evaluating factorial structure of the Screen for Child Anxiety Related Emotional Disorders (SCARED) questionnaire in an Italian clinical sample. under, Social Phobia and School Phobia. The novelty of this contribution is twofold: first, from a clinical point of view, we investigated the parent-child agreement level and examined separately the factorial structures of both parent and child versions of the SCARED for the first time in an Italian clinical sample. Second, unlike previous studies, we used statistical approaches specifically suited to account for the ordinal nature of the collected variables. METHOD: In a clinical sample of 171 children and adolescents aged 8-18 and their mothers we evaluated ...
*  Application of structural equation models to quality of life - Opus
Quality of life (QOL) has become an important concept for health care. As QOL is a multidimensional concept that is best evaluated by a number of latent constructs, it is well recognized that latent variable models, such as exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) are useful tools for analyzing QOL data. Recently, QOL researchers have realized the potential of structural equation modeling (SEM), which is a generalization of EFA and CFA in formulating a regression type equation in the model for studying the effects of the latent constructs to the QOL or health-related QOL. However, as the items in a QOL questionnaire are usually measured on an ordinal categorical scale, standard methods in SEM that are based on the normal distribution may produce misleading results. In this article, we propose an approach that uses a threshold specification to handle the ordinal categorical variables. Then, on the basis of ...
*  Confirmatory factor analysis, standardized estimates. T | Open-i
Confirmatory factor analysis, standardized estimates. TE = Treatment Effectiveness, GS = General Satisfaction, ID = Impact on Activities of Daily Living, CU = C
*  PPT - ANOVA Determining Which Means Differ in Single Factor Models PowerPoint Presentation - ID:6806389
ANOVA Determining Which Means Differ in Single Factor Models. Single Factor Models Review of Assumptions. Recall that the problem solved by ANOVA is to determine if at least one of the true mean values of several different treatments differs from the others. For ANOVA we assumed: Slideshow 6806389 by baxter-kemp
*  China's Food Security Evaluation Based on Factor Analysis - pdf descargar
China's Food Security Evaluation Based on Factor Analysis. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
*  Efficient Estimation of Approximate Factor Models via Regularized Maximum Likelihood - Munich Personal RePEc Archive
Alessi, L., Barigozzi, M. and Capassoc, M. (2010). Improved penalization for determining the number of factors in approximate factor models. Statistics and Probability Letters, 80, 1806-1813.. Bai, J. (2003). Inferential theory for factor models of large dimensions. Econometrica. 71 135-171.. Bai, J. and Li, K. (2012). Statistical analysis of factor models of high dimension. Ann. Statist. 40, 436-465.. Bai, J. and Ng, S.(2002). Determining the number of factors in approximate factor models. Econometrica. 70 191-221.. Bickel, P. and Levina, E. (2008a). Covariance regularization by thresholding. Ann. Statist. 36 2577-2604.. Bickel, P. and Levina, E. (2008b). Regularized estimation of large covariance matrices. Ann. Statist. 36 199-227.. Bien, J. and Tibshirani, R. (2011). Sparse estimation of a covariance matrix. Biometrika. 98, 807-820.. Breitung, J. and Tenhofen, J. (2011). ...
*  The psychological consequences of unemployment in South Africa
Table 5 shows that 87.1 per cent of the participants would prefer to find a job within a month. Further, 75.6 per cent expected to find work within a month. 42.3 per cent of the participants asked for a job every day, with 34.6 per cent asking once, twice or three times, while 6.3 per cent were not looking for a job at that time. Only 4.2 per cent of the participants never enquired about the availability of work, while 9.2 per cent never presented themselves for work.. Factor analysis. Exploratory factor analysis was used to explore the factor structure of the EUQ. A simple principal component analysis was carried out on the 26 items of the EUQ. An analysis of the eigenvalues (, 1.00; Tabachnick & Fidell, 2007) indicated that four factors explained 45.65 per cent of the variance. The scree plot confirmed that four factors could be extracted. A principal ...
*  Arbitrage, Factor Structure, and Mean-Variance Analysis on Large Asset Markets
Downloadable! We examine the implications of arbitrage in a market with many assets. The absence of arbitrage opportunities implies that the linear functionals that give the mean and cost of a portfolio are continuous; hence there exist unique portfolios that represent these functionals. These portfolios span the mean-variance efficient set. We resolve the question of when a market with many assets permits so much diversification that risk-free investment opportunities are available. Ross 112, 141 showed that if there is a factor structure, then the mean returns are approximately linear functions of factor loadings. We define an approximate factor structure and show that this weaker restriction is sufficient for Ross' result. If the covariance matrix of the asset returns has only K unbounded eigenvalues, then there is an approximate factor structure and it is unique. The corresponding K eigenvectors converge and play the role of ...
*  Search
This study aimed at using a multivariate approach to describe the body structure of Djallonke sheep in northern Ghana and to determine which approach explains better the variation in body composition. Live weight (LW) and linear body measurements including heart girth (HG), neck girth (NG), chest depth (CD), height at withers (HW), rump height (RH), body length (BL) and pin-bone width (PBW) were obtained from 172 sheep aged between two and three years. The fixed effects of sex and age were tested using the general linear model (GLM) while the Nearest Neighbor method of Hierarchical Cluster Analysis was used to group body traits into clusters. Principal Component Factor Analysis was used to describe the variation in body traits where extracted factors were varimax rotated to enhance interpretability. The analysis of variance revealed significant (P < 0.01) differences in the morphological traits of the two sexes with higher ...
*  Aid, Exports, and Growth; A Time-Series Perspective on the Dutch Disease Hypothesis
Downloadable! We use a heterogeneous panel VAR model identified through factor analysis to study the dynamic response of exports, imports, and per capita GDP growth to a
*  Hur mäts idrottstränares beteenden? : En svensk översättning och validering av skattningsskalan Coaching Behavior Scale for...
Aim. The purpose of the study was to translate and validate the Coaching Behavior Scale for Sports (CBS-S) from English to Swedish.. Method. A total of 545 participants were distributed in two samples. The participants were team sport athletes from teams in the two highest national levels. The participants answered a questionnaire consisting of CBS-S and scales for other coaching behaviors, motivation, self-confidence and the relationship with the coach. On the data an exploratory factor analysis with varimax rotation was performed and correlations between the different dimensions in the scales were computed. 39 of the participants also answered CBS-S twice and on this data test-retest correlation were computed between the dimensions in CBS-S.. Results. The factor analysis found eight dimensions with Eigenvalue , 1. The relationships between coaching behaviors in CBS-S and other coaching behaviors, motivation, self-confidence and the ...
*  Temporal Dynamics of Host Molecular Responses Differentiate Symptomatic and Asymptomatic Influenza A Infection
Author Summary The transcriptional responses of human hosts towards influenza viral pathogens are important for understanding virus-mediated immunopathology. Despite great advances gained through studies using model organisms, the complete temporal host transcriptional responses in a natural human system are poorly understood. In a human challenge study using live influenza (H3N2/Wisconsin) viruses, we conducted a clinically uninformed (unsupervised) factor analysis on gene expression profiles and established an ab initio molecular signature that strongly correlates to symptomatic clinical disease. This is followed by the identification of 42 biomarkers whose expression patterns best differentiate early from late phases of infection. In parallel, a clinically informed (supervised) analysis revealed over-stimulation of multiple viral sensing pathways in symptomatic hosts and linked their temporal trajectory with development of diverse clinical signs and ...
*  Pricing Interest Rate Derivatives in a Non-Parametric Two-Factor Term-Structure Model
Downloadable! Diffusion functions in term-structure models are measures of uncertainty about future price movements and are directly related to the risk associated with holding financial securities. Correct specification of diffusion functions is crucial in pricing options and other derivative securities. In contrast to the standard parametric two-factor models, we propose a non-parametric two-factor term-structure model that imposes no restrictions on the functional forms of the diffusion functions. Hence, this model allows for maximum flexibility when fitting diffusion functions into data. A non-parametric procedure is developed for estimating the diffusion functions, based on the discretely sampled observations. The convergence properties and the asymptotic distributions of the proposed non-parametric estimators of the diffusion functions with multivariate dimensions are also obtained. Based on U.S. data, the non-parametric prices of the bonds and bond options are ...
*  Example 37.5 Creating Path Diagrams for Factor Solutions :: SAS/STAT(R) 13.2 User's Guide
The path diagram in Output 37.5.3 also represents factor variances and error variances by double-headed links. However, each of these links points to an individual variable, rather than to a pair of variables as the double-headed links for correlations do. The path diagram also displays the numerical values of factor variances or error variances next to the associated links. The directed links from factors to variables in the path diagram represent the effects of factors on the variables. The path diagram displays the numerical values of these effects, which are the loading estimates that are shown in Output 37.5.2. However, to aid the interpretation of the factors, the path diagram does not show all factor loadings or their corresponding links. By default, the path diagram displays only the links that have loadings greater than 0.3 in magnitude. For example, instead of associating ...
*  Interaction Effects in Factorial Analysis of Variance ISBN13:9780761912217 ISBN10:0761912215 - TextbookRush
Get the best deals on Interaction Effects in Factorial Analysis of Variance ISBN13:9780761912217 ISBN10:0761912215 from TextbookRush at a great price and get free shipping on orders over $35!
*  Hormozgan Medical Journal
p,Introduction: This study aims at analyzing factor structure of Short Form Healthy Survey (SF-36), Persian Version, for both normal people and patients with chronic diseases. Methods: In this cross-sectional study, a total of 585 patients with chronic diseases and 642 over 18-years old normal people were selected using simple casual sampling method. When the survey was completed by the participants, the Cronbach's alpha coefficient and confirmatory factor analysis (CFA) were used to determine the survey's validity and reliability. T-test also was used to compare the average score of the survey's domains in both groups. Results: For the group of patients with the chronic diseases, the highest mean belonged to the social functioning domain's score (43.11±18.48). In contrast, for the normal people's group, vitality found the highest mean score (50.83±9.95). T-test results showed that the mean difference in all domains except the role limitations ...
*  Dynamic Specification Tests for Dynamic Factor Models
Downloadable! We derive computationally simple and intuitive expressions for score tests of neglected serial correlation in common and idiosyncratic factors in dynamic factor models using frequency domain techniques. The implied time domain orthogonality conditions are analogous to the conditions obtained by treating the smoothed estimators of the innovations in the latent factors as if they were observed, but they account for their final estimation errors. Monte Carlo exercises confirm the finite sample reliability and power of our proposed tests. Finally, we illustrate their empirical usefulness in an application that constructs a monthly coincident indicator for the US from four macro series.
*  Newbie stats help: How to safely interpret Total Variance Explained -Factor analysis
Hi all, I have run a factor analysis to test reliability and validity of an established scale and found simple structure with my own sample, which is great. I found a difference between the factors that explain most of the variance in the established study and my study. Now I am discussing my results and I interpreted this finding like this for example: Seeing though most of the variance explained was by X factor and not Y factor (as suggested by the scale autors) this suggests that X
*  A test of Ledoit-Wolf versus a factor model | R-bloggers
Statistical factor models and Ledoit-Wolf shrinkage are competing methods for estimating variance matrices of returns. So which is better? This adds a data
*  Again with Ledoit-Wolf and factor models | R-bloggers
We come closer to a definitive answer on the relative merit of Ledoit-Wolf shrinkage versus a statistical factor model for variance matrices. Previously This
*  Evolution in Four Dimensions: Genetic, Epigenetic, Behavioral, and Symbolic Variation in the History of Life Free Download Pdf
Jablonka and Lamb present a richer, more complex view of evolution than that offered by the gene-based Modern Synthesis, arguing that induced and acquired changes also play a role. Their lucid and accessible text is accompanied by artist-physician Anna Zeligowski's lively drawings, which humorously and effectively illustrate the authors' points. Each chapter ends with a dialogue in which the authors refine their arguments against the vigorous skepticism of the fictional "I.M." (for Ipcha Mistabra - Aramaic for "the opposite conjecture"). The extensive new chapter, presented engagingly as a dialogue with I.M., updates the information on each of the four dimensions - with special attention to the epigenetic, where there has been an explosion of new research.. Praise for the first edition. "With courage and verve, and in a style accessible to general readers, Jablonka and Lamb lay out some of the exciting new pathways of Darwinian evolution that have been uncovered by contemporary research." - ...
*  Evolution in Four Dimensions | Welcome to my website, containing a number of essays which take an alternative, often dissident...
Inherently limited - a review of Evolution in Four Dimensions. Since the late 19th century, when scientists established beyond doubt that conception consists of the fusion between one sperm and one egg to form one cell, one of biology's chief tasks was to explain how all the information needed to make a complex organism could be contained in a single fertilised egg cell. When it was discovered that all cell nuclei contain chromosomes which are all replicated prior to cell division, biologists concentrated all their attention on those chromosomes as the containers of inheritable information. By the 1950s, it had been established that those chromosomes contain very long-chain molecules, known as DNA, whose linear sequences of bases contain coded instructions for making nearly all the molecules needed for the construction and maintenance of an organism's body. Furthermore, the method by which chromosomes become replicated was confirmed. Though the process is susceptible to accidental errors, it was ...