48 research outputs found
Confirmatory Factor Analysis using Amos, LISREL, Mplus, SAS/STAT CALIS
Factor analysis is a statistical method used to find a small set of unobserved variables (also called latent variables, or factors) which can account for the covariance among a larger set of observed variables (also called manifest variables). A factor is an unobservable variable that is assumed to influence observed variables. Scores on multiple tests may be indicators of intelligence (Spearman, 1904); political liberties and popular sovereignty may measure the quality of a country’s democracy (Bollen, 1980); or issue emphases in election manifestos may signify a political party’s underlying ideology (Gabel & Huber, 2000). Factor analysis is also used to assess the reliability and validity of measurement scales (Carmines & Zeller, 1979)
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Changing behaviour 'more or less'-do theories of behaviour inform strategies for implementation and de-implementation? A critical interpretive synthesis
BACKGROUND: Implementing evidence-based care requires healthcare practitioners to do less of some things (de-implementation) and more of others (implementation). Variations in effectiveness of behaviour change interventions may result from failure to consider a distinction between approaches by which behaviour increases and decreases in frequency. The distinction is not well represented in methods for designing interventions. This review aimed to identify whether there is a theoretical rationale to support this distinction. METHODS: Using Critical Interpretative Synthesis, this conceptual review included papers from a broad range of fields (biology, psychology, education, business) likely to report approaches for increasing or decreasing behaviour. Articles were identified from databases using search terms related to theory and behaviour change. Articles reporting changes in frequency of behaviour and explicit use of theory were included. Data extracted were direction of behaviour change, how theory was operationalised, and theory-based recommendations for behaviour change. Analyses of extracted data were conducted iteratively and involved inductive coding and critical exploration of ideas and purposive sampling of additional papers to explore theoretical concepts in greater detail. RESULTS: Critical analysis of 66 papers and their theoretical sources identified three key findings: (1) 9 of the 15 behavioural theories identified do not distinguish between implementation and de-implementation (5 theories were applied to only implementation or de-implementation, not both); (2) a common strategy for decreasing frequency was substituting one behaviour with another. No theoretical basis for this strategy was articulated, nor were methods proposed for selecting appropriate substitute behaviours; (3) Operant Learning Theory makes an explicit distinction between techniques for increasing and decreasing frequency. DISCUSSION: Behavioural theories provide little insight into the distinction between implementation and de-implementation. Operant Learning Theory identified different strategies for implementation and de-implementation, but these strategies may not be acceptable in health systems. Additionally, if behaviour substitution is an approach for de-implementation, further investigation may inform methods or rationale for selecting the substitute behaviour
Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans
Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have
fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in
25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16
regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of
correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP,
while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in
Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium
(LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region.
Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant
enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the
refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa,
an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of
PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent
signals within the same regio
What Makes Retirees Happier: A Gradual or 'Cold Turkey' Retirement?
This study explores the factors that affect an individual’s happiness while transitioning into retirement. Recent studies highlight gradual retirement as an attractive option to older workers as they approach full retirement. However, it is not clear whether phasing or cold turkey makes for a happier retirement. Using longitudinal data from the Health and Retirement Study, this study explores what shapes the change in happiness between the last wave of full employment and the first wave of full retirement. Results suggest that what really matters is not the type of transition (gradual retirement or cold turkey), but whether people perceive the transition as chosen or forced
Does the number of parties to place affect the placement of parties? Results from an expert survey experiment
Expert surveys are frequently used in comparative politics to measure the ideological locations of political parties. However, it is possible that increasing the number of parties to place systematically biases results as experts try to fit more actors onto a common space. We test this possibility with an experiment embedded in an “expert” survey – with graduate students serving as our pool of experts to ensure an adequate sample size – by varying the number of parties to be placed in the United Kingdom and Germany. We find some tendency for the variance of Labour and SPD placements to diminish when more parties are present, and for SPD placements to move toward the center given more parties. However, we find no consistent evidence that the number of parties systematically affects mean or median party placements. Our results support the reliability of expert surveys as an indicator of party ideology
Deconstructing the time-out: What do mothers understand about a common disciplinary procedure?
Time-out (TO) is one of the most common and effective disciplinary tactics used to address problem behavior; however, parents rate TO as one of the least useful behavior modification techniques. This may be due to a discrepancy between empirically supported TO procedures and how mothers are actually conducting TO. Fifty-five mothers were asked to define TO, provide information on how they conduct TO, and identify errors in TO procedures. Results indicate that maternal knowledge and implementation of TO differs considerably from the empirical ideal, potentially impacting the utility and frequency of TO usage in the home to address child problem behaviors
Short-term Climate Variabiliy Models - directory 4 of 16
Contains Model output data for Short-term Climate Variability Models for species in the genera Caracara, Cardellina, Cardinalis, Carpodacus, Cathartes, Catharus, Catherpes, Certhia, Chaetura, Chamaea, Charadrius, Chlidonias, Chloroceryle, and Chondestes
Long-Term Climate Average Models 2
Second half of data for species distribution models for long-term climate average model