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Multiple Indicators (multiple + indicator)
Selected AbstractsA stronger latent-variable methodology to actual,ideal discrepancyEUROPEAN JOURNAL OF PERSONALITY, Issue 7 2008L. Francesca Scalas Abstract We introduce a latent actual,ideal discrepancy (LAID) approach based on structural equation models (SEMs) with multiple indicators and empirically weighted variables. In Study 1, we demonstrate with simulated data, the superiority of a weighted approach to discrepancy in comparison to a classic unweighted one. In Study 2, we evaluate the effects of actual and ideal appearance on physical self-concept and self-esteem. Actual appearance contributes positively to physical self-concept and self-esteem, whereas ideal appearance contributes negatively. In support of multidimensional perspective, actual - and ideal -appearance effects on self-esteem are substantially,but not completely,mediated by physical self-concept. Whereas this pattern of results generalises across gender and age, multiple-group invariance tests show that the effect of actual appearance on physical self-concept is larger for women than for men. Copyright © 2008 John Wiley & Sons, Ltd. [source] Water Framework Directive: ecological classification of Danish lakesJOURNAL OF APPLIED ECOLOGY, Issue 4 2005MARTIN SØNDERGAARD Summary 1The European Water Framework Directive (WFD) requires that all European waterbodies are assigned to one of five ecological classes, based primarily on biological indicators, and that minimum good ecological quality is obtained by 2015. However, the directive provides only general guidance regarding indicator definitions and determination of boundaries between classes. 2We used chemical and biological data from 709 Danish lakes to investigate whether and how lake types respond differently to eutrophication. In the absence of well-defined reference conditions, lakes were grouped according to alkalinity and water depth, and the responses to eutrophication were ordered along a total phosphorus (TP) gradient to test the applicability of pre-defined boundaries. 3As a preliminary classification we suggest a TP-based classification into high, good, moderate, bad and poor ecological quality using 0,25, 25,50, 50,100, 100,200 and > 200 µg P L,1 boundaries for shallow lakes, and 0,12·5, 12·5,25, 25,50, 50,100 and > 100 µg P L,1 boundaries for deep lakes. Within each TP category, median values are used to define preliminary boundaries for the biological indicators. 4Most indicators responded strongly to increasing TP, but there were only minor differences between low and high alkalinity lakes and modest variations between deep and shallow lakes. The variability of indicators within a given TP range was, however, high, and for most indicators there was a considerable overlap between adjacent TP categories. Cyanophyte biomass, submerged macrophyte coverage, fish numbers and chlorophyll a were among the ,best' indicators, but their ability to separate different TP classes varied with TP. 5When using multiple indicators the risk that one or more indicators will indicate different ecological classes is high because of a high variability of all indicators within a specific TP class, and the ,one out , all out' principle in relation to indicators does not seem feasible. Alternatively a certain compliance level or a ,mean value' of the indicators can be used to define ecological classes. A precise ecological quality ratio (EQR) using values between 0 and 1 can be calculated based on the extent to which the total number of indicators meets the boundary conditions, as demonstrated from three Danish lakes. 6Synthesis and applications. The analysis of Danish lakes has identified a number of useful indicators for lake quality and has suggested a method for calculating an ecological quality ratio. However, it also demonstrates that the implementation of the Water Framework Directive faces several challenges: gradual rather than stepwise changes for all indicators, large variability of indicators within lake classes, and problems using the one out , all out principle for lake classification. [source] A Metric of Maternal Prenatal Risk Drinking Predicts Neurobehavioral Outcomes in Preschool ChildrenALCOHOLISM, Issue 4 2009Lisa M. Chiodo Background:, Fetal Alcohol Spectrum Disorders (FASDs), including Fetal Alcohol Syndrome, continue to be high-incidence developmental disorders. Detection of patterns of maternal drinking that place fetuses at risk for these disorders is critical to diagnosis, treatment, and prevention, but is challenging and often insufficient during pregnancy. Various screens and measures have been used to identify maternal risk drinking but their ability to predict child outcome has been inconsistent. This study hypothesized that a metric of fetal "at-risk" alcohol exposure (ARAE) derived from several indicators of maternal self-reported drinking would predict alcohol-related neurobehavioral dysfunctions in children better than individual measures of maternal alcohol consumption alone. Methods:, Self-reported peri-conceptional and repeated maternal drinking during pregnancy were assessed with semi-structured interviews and standard screens, i.e., the CAGE, T-ACE, and MAST, in a prospective sample of 75 African-American mothers. Drinking volumes per beverage type were converted to standard quantity and frequency measures. From these individual measures and screening instruments, a simple dichotomous index of prenatal ARAE was defined and used to predict neurobehavioral outcomes in the 4- to 5-year-old offspring of these women. Study outcomes included IQ, attention, memory, visual-motor integration, fine motor skill, and behavior. Statistical analyses controlled for demographic and other potential confounders. Results:, The current "at-risk" drinking metric identified over 62% of the mothers as drinking at risk levels,23% more than the selection criterion identified,and outperformed all individual quantity and frequency consumption measures, including averages of weekly alcohol use and "binge" alcohol exposures (assessed as intake per drinking occasion), as well as an estimate of the Maternal Substance Abuse Checklist (Coles et al., 2000), in predicting prenatal alcohol-related cognitive and behavioral dysfunction in 4- to 5-year-old children. Conclusions:, A metric reflecting multiple indices of "at-risk" maternal alcohol drinking in pregnancy had greater utility in predicting various prenatal alcohol-related neurobehavioral dysfunction and deficits in children compared to individual measures of maternal self-reported alcohol consumption or a previous maternal substance abuse index. Assessing fetal risk drinking in pregnant women was improved by including multiple indicators of both alcohol consumption and alcohol-related consequences and, if appropriate practical applications are devised, may facilitate intervention by health care workers during pregnancy and potentially reduce the incidence or severity of FASDs. [source] Factorial Invariance Within Longitudinal Structural Equation Models: Measuring the Same Construct Across TimeCHILD DEVELOPMENT PERSPECTIVES, Issue 1 2010Keith F. Widaman Abstract, Charting change in behavior as a function of age and investigating longitudinal relations among constructs are primary goals of developmental research. Traditionally, researchers rely on a single measure (e.g., scale score) for a given construct for each person at each occasion of measurement, assuming that measure reflects the same construct at each occasion. With multiple indicators of a latent construct at each time of measurement, the researcher can evaluate whether factorial invariance holds. If factorial invariance constraints are satisfied, latent variable scores at each time of measurement are on the same metric and stronger conclusions are warranted. This article discusses factorial invariance in longitudinal studies, contrasting analytic approaches and highlighting strengths of the multiple-indicator approach to modeling developmental processes. [source] |