booktitle = "2019 IEEE Congress on Evolutionary Computation (CEC)",
title = "User and Task Identification of Smartwatch Data with
an Ensemble of Nonlinear Symbolic Models",
year = "2019",
pages = "2506--2513",
abstract = "Smart devices are becoming more universally adopted
and can be used to track and model user activity and
monitor for abnormalities. Deviations from what is
expected may indicate that a fall is imminent or that
an injury has been sustained. Healthcare practitioners
can use descriptive models of human kinematics as a
tool to monitor patient recovery. This work extends
previous work which generated descriptive nonlinear
symbolic models of human kinematics with genetic
programming. Previously, linear models were developed
and compared to the nonlinear models. Although the
linear models fit the data well, they were
significantly worse than the nonlinear models. In this
phase of the project, ensembles of nonlinear models
were created to more accurately fit and classify data.
Different model selection strategies for the ensembles
were investigated. As one would expect, ensembles of
models were significantly better than a single model
classifier. It was also observed that, although more
models in the ensemble yielded better results, only 2
models were required to obtain significantly better
results. It was also observed that a random model
selection strategy for the ensembles produced
competitive results when compared to a more rigorous
model selection strategy.",