Title: Registration for exponential family functional data
Authors: Julia Wrobel - University of Colorado School of Public Health (United States) [presenting]
Jeff Goldsmith - Columbia University (United States)
Abstract: The problem of aligning curves from exponential family distributions is considered. The approach is based on the combination of alignment and functional principal components analysis, and is facilitated by recent extensions of FPCA to non-Gaussian settings. The motivation comes from the physical activity using accelerometers, wearable devices that provide around-the-clock monitoring of activity and produce non-Gaussian measurements. We apply the proposed methods to activity counts using a binary active vs inactive indicator using a binomial distribution. After alignment, the trajectories show clear peaks of activity in the morning and afternoon with a dip in the middle of the day.