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Updated: May 18, 2026

06:49
Evaluation of a Smartphone-based Human Activity Recognition System in a Daily Living Environment
Published on: December 11, 2015
Duration discretisation for activity recognition.
Priyanka Chaurasia1, Sally McClean, Bryan Scotney
1School of Computing and Information Engineering, University of Ulster, Coleraine, Northern Ireland, UK. chaurasia-p@email.ulster.ac.uk
Summary
Discretizing activity durations using clustering improves activity recognition in smart environments. Incorporating this duration information enhances prediction accuracy by nearly 3%.
Area of Science:
- Computer Science
- Artificial Intelligence
- Human-Computer Interaction
Background:
- Activity recognition is crucial for smart environments and assistive technologies.
- Learning activities from sensor data is complex, with activity duration being a key, yet challenging, parameter.
- Directly using continuous duration values in models can be difficult and less effective.
Purpose of the Study:
- To discretize activity durations using various clustering algorithms.
- To develop a probabilistic model that predicts activities and individuals based on sensor data, time, and discrete durations.
- To evaluate the impact of duration discretization on activity prediction performance.
Main Methods:
- Exploration of clustering algorithms, from visual inspection to model-based clustering, for duration discretization.
- Development of a probabilistic model integrating sensor sequences, time, and discrete duration values.
- Comparative analysis of different models based on their activity prediction accuracy.
Main Results:
- Discretizing activity durations using clustering algorithms was explored.
- A probabilistic model was successfully built incorporating discrete duration values.
- Incorporating duration information consistently improved prediction performance across different clustering methods.
Conclusions:
- Discretization of activity durations using clustering is a viable approach.
- Integrating discrete duration information significantly enhances activity recognition model performance.
- The study demonstrates a nearly 3% improvement in prediction accuracy by including duration data.
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