Search results for "variance components"
showing 9 items of 9 documents
Investigating applicability of ratings of indicators of the CLASS Pre-K instrument
2022
When classroom observations are increasingly used for accountability and evaluation purposes, a deeper understanding of the psychometric properties of such measurement tools is needed. The present study took a unique approach to examine the psychometric properties of a commonly used classroom observation measure by testing the reliability of indicators for higher-order constructs (i.e. dimensions). We investigated the reliability of indicator ratings of the Classroom Assessment Scoring System (CLASS) Pre-K instrument in Finnish kindergarten and first grade classrooms. Twenty-one observer pairs rated 838 segments identified from the 413 lessons of 48 teachers. Variance components models were…
Healthy and unhealthy eating at lower secondary school in Norway
2010
Aims: To assess adolescents’ eating/drinking habits of a selection of healthy and unhealthy food items at school, variations in gender and socioeconomic status in these eating habits, and variations between the schools. Methods: A cross-sectional study among 2870 adolescents (mean age: 15.5 years) within the Fruits and Vegetables Make the Marks (FVMM) project. A survey questionnaire was completed by the pupils in the classroom in the presence of a trained project worker. One school lesson (45 minutes) was used to complete the questionnaire. A total of two healthy (fruit and vegetables (FV), water) and five unhealthy (candy and/or potato chips, sweet bakery, instant noodles, regular soft dr…
Replication of linkage of familial hypobetalipoproteinemia to chromosome 3p in six kindreds
2002
Familial hypobetalipoproteinemia (FHBL) is a genetically heterogeneous condition characterized by very low apolipoprotein B (apoB) concentrations in plasma and/or low levels of LDL-cholesterol (LDL-C) with a propensity to developing fatty liver. In a minority of cases, truncation-specifying mutations of the apoB gene (APOB) are etiologic, but the genetic basis of most cases is unknown. We previously reported linkage of FHBL to a 10 cM region on 3p21.1-22 in one kindred. The objectives of the current study were to identify other FHBL families with linkage to 3p and to narrow the FHBL susceptibility region on 3p. Six additional FHBL kindreds unlinked to the APOB region on chromosome 2 were ge…
Reference Priors in a Variance Components Problem
1992
The ordered group reference prior algorithm of Berger and Bernardo (1989b) is applied to the balanced variance components problem. Besides the intrinsic interest of developing good noninformative priors for the variance components problem, a number of theoretically interesting issues arise in application of the proposed procedure. The algorithm is described (for completeness) in an important special case, with a detailed heuristic motivation.
Widespread pain among 11-year-old Finnish twin pairs
2001
Objective To examine the prevalence of widespread musculoskeletal pain (WSP) symptoms in 11-year-old Finnish twins and to determine the relative role of genetic and environmental factors in the etiology of WSP. Methods Data on current pain items were collected from 1995 to 1998 from a national sample of Finnish families with 11-year-old twins born between 1984 and 1987. The presence of WSP was determined using a validated questionnaire method. Pairwise similarity was computed for 583 monozygotic (MZ) pairs, 588 same-sex dizygotic (DZ) pairs, and 618 opposite-sex DZ twin pairs. Variance components for genetic and environmental factors were estimated using biometric structural equation modeli…
Higher education and the development of competencies for innovation in the workplace
2012
PurposeThis paper aims to analyze the production function nexus between higher education practice and the development of innovation‐related competencies by university graduates in Spain. The research hypothesis is the presence of statistically significant relationships between the development of innovational competencies and the modes of teaching and learning used in higher education practice.Design/methodology/approachThe relationships are modeled through a set of stochastic frontier and variance component equations with the development of each competency as the dependent variable. The main explanatory variables capture the prevalence of diverse teaching/learning modes and the behavior of …
Repeatability of Feather Mite Prevalence and Intensity in Passerine Birds
2014
Understanding why host species differ so much in symbiont loads and how this depends on ecological host and symbiont traits is a major issue in the ecology of symbiosis. A first step in this inquiry is to know whether observed differences among host species are species-specific traits or more related with host-symbiont environmental conditions. Here we analysed the repeatability (R) of the intensity and the prevalence of feather mites to partition within- and among-host species variance components. We compiled the largest dataset so far available: 119 Paleartic passerine bird species, 75,944 individual birds, ca. 1.8 million mites, seven countries, 23 study years. Several analyses and appro…
Shoot age as a confounding factor on detecting the effect of human-induced disturbance on Posidonia oceanica growth performance
2007
Abstract The response of orthotropic rhizome elongation and primary production of Posidonia oceanica to anthropogenic perturbations and potential confounding effects of shoot age were assessed using a Linear Multilevel Model (LMM). This model examined the confounding effect of age by comparing the estimates of impact and variance components obtained by excluding and including Age as an explanatory variable. Age had a negative effect on rhizome elongation and primary production with an annual decrease of 0.6 mm y − 1 and 7 mg dw y − 1 respectively. According to the LMM when age effect was omitted, the differences between disturbed and control locations in rhizome elongation and primary produ…
Variance component analysis to assess protein quantification in biomarker discovery. Application to MALDI-TOF mass spectrometry.
2017
International audience; Controlling the technological variability on an analytical chain is critical for biomarker discovery. The sources of technological variability should be modeled, which calls for specific experimental design, signal processing, and statistical analysis. Furthermore, with unbalanced data, the various components of variability cannot be estimated with the sequential or adjusted sums of squares of usual software programs. We propose a novel approach to variance component analysis with application to the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) technology and use this approach for protein quantification by a classical signal processing algori…