Dr Andrew Smith's Outputs (49)

Prenatal exposure to maternal smoking and offspring DNA methylation across the lifecourse: Findings from the Avon Longitudinal Study of Parents and Children (ALSPAC) (2014)
Journal Article

© The Author 2014. Maternal smoking during pregnancy has been found to influence newborn DNA methylation in genes involved in fundamental developmental processes. It is pertinent to understand the degree to which the offspring methylomeis sensitive t... Read More about Prenatal exposure to maternal smoking and offspring DNA methylation across the lifecourse: Findings from the Avon Longitudinal Study of Parents and Children (ALSPAC).

Dietary patterns and changes in body composition in children between 9 and 11 years (2014)
Journal Article

Objective: Childhood obesity is rising and dietary intake is a potentially modifiable factor that plays an important role in its development. We aim to investigate the association between dietary patterns, obtained through principal components analys... Read More about Dietary patterns and changes in body composition in children between 9 and 11 years.

Dietary patterns in UK adolescents obtained from a dual-source FFQ and their associations with socio-economic position, nutrient intake and modes of eating (2013)
Journal Article

Objective To derive dietary patterns using principal components analysis from separate FFQ completed by mothers and their teenagers and to assess associations with nutrient intakes and sociodemographic variables. Design Two distinct FFQ were complete... Read More about Dietary patterns in UK adolescents obtained from a dual-source FFQ and their associations with socio-economic position, nutrient intake and modes of eating.

Quadratic programming and penalized regression (2013)
Presentation / Conference Contribution

Quadratic programming is a versatile tool for calculating estimates in penalized regression. It can be used to produce estimates based on L1 roughness penalties, as in total variation denoising. In particular, it can calculate estimates when the roug... Read More about Quadratic programming and penalized regression.

Longitudinal comparisons of dietary patterns derived by cluster analysis in 7- to 13-year-old children (2012)
Journal Article

Little is known about changes in dietary patterns over time. The present study aims to derive dietary patterns using cluster analysis at three ages in children and track these patterns over time. In all, 3 d diet diaries were completed for children f... Read More about Longitudinal comparisons of dietary patterns derived by cluster analysis in 7- to 13-year-old children.

Dietary patterns obtained through principal components analysis: The effect of input variable quantification (2012)
Journal Article

Principal components analysis (PCA) is a popular method for deriving dietary patterns. A number of decisions must be made throughout the analytic process, including how to quantify the input variables of the PCA. The present study aims to compare the... Read More about Dietary patterns obtained through principal components analysis: The effect of input variable quantification.

Nonparametric Regression on a Graph (2011)
Journal Article

The 'Signal plus Noise' model for nonparametric regression can be extended to the case of observations taken at the vertices of a graph. This model includes many familiar regression problems. This article discusses the use of the edges of a graph to... Read More about Nonparametric Regression on a Graph.

A comparison of dietary patterns derived by cluster and principal components analysis in a UK cohort of children (2011)
Journal Article

Background/Objectives: The objective of this study was to identify dietary patterns in a cohort of 7-year-old children through cluster analysis, compare with patterns derived by principal components analysis (PCA), and investigate associations with s... Read More about A comparison of dietary patterns derived by cluster and principal components analysis in a UK cohort of children.

Streamlined variance calculations for semiparametric mixed models (2007)
Journal Article

Semiparametric mixed model analysis benefits from variability estimates such as standard errors of effect estimates and variability bars to accompany curve estimates. We show how the underlying variance calculations can be done extremely efficiently... Read More about Streamlined variance calculations for semiparametric mixed models.