Jaroslaw (Jarek) Harezlak, of the Department of Epidemiology and Biostatistics at Indiana University – Bloomington, will present: “What can the Raw Accelerometry Data Tell us about Human Activity – Walking vs. Stair Climbing”.
Abstract: Wearable accelerometers offer a noninvasive measure of physical activity (PA). They record high frequency three-dimensional time series data. Among many human activities, walking is the most common moderate level PA. Our work addresses the classification of walking into level walking, descending stairs and ascending stairs. We apply our method, based on the extracted short-time interpretable features arising from the Fourier and wavelet transforms, to data collected on 32 middle-age participants. We build subject-specific and group-level classification models utilizing a tree-based classifier. We evaluate the effects of sensor location and tuning parameters on the classification accuracy of these models. In the group-level classification setting, we propose a robust feature normalization approach and evaluate its performance. In summary, our work provides a framework for better extraction and use of the raw accelerometry data to differentiate among different walking modalities. We show that both at a subject-specific level and at a group level, overall classification accuracy is above 80% indicating excellent performance of our method.
A social tea will be held at 3:00 p.m. in A434 Mayo. All are Welcome.