Advancements in accelerometer analytic and visualization techniques allow researchers to
more precisely identify and compare critical periods of physical activity (PA) decline by age …

The NHANES study contains objectively measured physical activity data collected using hip-
worn accelerometers from multiple cohorts. However, using the accelerometry data has …

Our goal is to provide an easy-to-follow applied book on semiparametric regression
methods using R. Semiparametric regression has a large literature, but much of it is geared …

Emerging technologies generate data sets of increased size and complexity that require
new or updated statistical inferential methods and scalable, reproducible software. These …

We introduce fast multilevel functional principal component analysis (fast MFPCA), which
scales up to high dimensional functional data measured at multiple visits. The new approach …

We consider dependent functional data that are correlated because of a longitudinal‐based
design: each subject is observed at repeated times and at each time, a functional …

Smoothing of noisy sample covariances is an important component in functional data
analysis. We propose a novel covariance smoothing method based on penalized splines …

Objective measurement of physical activity using wearable devices such as accelerometers
may provide tantalizing new insights into the association between activity and health …

We propose the additive functional Cox model to flexibly quantify the association between
functional covariates and time to event data. The model extends the linear functional …

Epidemiological research supports an association between maternal exposure to air
pollution during pregnancy and adverse children's health outcomes. Advances in exposure …