Example data set: NHANES 2003-2006

The rapid growth of wearable devices has made it possible to collect high-resolution, objectively measured physical activity data. In the National Health and Nutrition Examination Survey (NHANES) 2003-2006, approximately 14000 people were asked to wear a hip-worn accelerometer for seven consecutive days while maintaining their normal life activities. Tri-axial accelerations were collected and released as minute-level activity counts (AC). Here is a tutorial to obtain a ready-to-use NHANES data set.

The statistical analysis of this data set is challenging because (1) it contains many participants (large n) and many covariates (large p); (2) each participant has multiple days of data, which induces a multilevel structure; (3) for each day, physical activity data are high-dimensional; (4) the activity counts exhibit non-stationary behavior across time of the day.