53 citations · 153 across the 6 of their papers we have counts for
7 papers
Shape-constrained Estimation in Functional Regression with Bernstein Polynomials
Rahul Ghosal, Sujit Ghosh, Jacek Urbanek +2
Shape restrictions on functional regression coefficients such as non-negativity, monotonicity, convexity or concavity are often available in the form of a prior knowledge or requir…
Scalar on time-by-distribution regression and its application for modelling associations between daily-living physical activity and cognitive functions in Alzheimer's Disease
Rahul Ghosal, Vijay R. Varma, Dmitri Volfson +4
Wearable data is a rich source of information that can provide deeper understanding of links between human behaviours and human health. Existing modelling approaches use wearable d…
Distributional data analysis via quantile functions and its application to modelling digital biomarkers of gait in Alzheimer's Disease
Rahul Ghosal, Vijay R. Varma, Dmitri Volfson +5
With the advent of continuous health monitoring with wearable devices, users now generate their unique streams of continuous data such as minute-level step counts or heartbeats. Su…
Epidemiology of Objectively Measured Bedtime and Chronotype in the US adolescents and adults: NHANES 2003-2006
Jacek K. Urbanek, Adam Spira, Junrui Di +3
Background: We propose a method for estimating the timing of in-bed intervals using objective data in a large representative U.S. sample, and quantify the association between these…
Validation of gait characteristics extracted from raw accelerometry during walking against measures of physical function, mobility, fatigability, and fitness
Jacek K. Urbanek, Vadim Zipunnikov, Tamara Harris +3
Background. Wearable accelerometry devices allow collection of high-density activity data in large epidemiological studies both in-the-lab as well as in-the-wild (free-living). Suc…
Stride variability measures derived from wrist- and hip-worn accelerometers
Jacek K. Urbanek, Jaroslaw Harezlak, Nancy W. Glynn +3
Many epidemiological and clinical studies use accelerometry to objectively measure physical activity using the activity counts, vector magnitude, or number of steps. These measures…
Prediction of sustained harmonic walking in the free-living environment using raw accelerometry data
Jacek K. Urbanek, Vadim Zipunnikov, Tamara Harris +6
Objective. Using raw, sub-second level, accelerometry data, we propose and validate a method for identifying and characterizing walking in the free-living environment. We focus on…