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Identifiability and predictability of integer- and fractional-order epidemiological models using physics-informed
Ehsan Kharazmi1, Min Cai1,2, Xiaoning Zheng1,3
1Division of Applied Mathematics, Brown University, Providence, RI, USA.
Physics-informed neural networks (PINNs) identified time-dependent parameters and fractional operators in epidemiological models. This approach accurately forecasts COVID-19 spread by inferring unknown dynamics and parameters.
Area of Science:
- Epidemiology
- Computational Mathematics
- Machine Learning
Background:
- Epidemiological models are crucial for understanding disease spread.
- Traditional models often struggle with time-varying parameters and complex dynamics.
- Physics-informed neural networks (PINNs) offer a novel approach to address these limitations.
Purpose of the Study:
- To apply PINNs for identifying time-dependent parameters and fractional differential operators in epidemiological models.
- To analyze variations of the susceptible-infectious-removed (SIR) model, including fractional-order and time-delay models.
- To investigate the identifiability and uncertainty quantification for these models in real-world pandemic forecasting.
Main Methods:
- Utilized PINNs to analyze epidemiological models, including SIR variations.
- Incorporated fractional-order and time-delay dynamics into the models.
- Represented time-dependent parameters and fractional orders using neural networks.
- Applied the methodology to COVID-19 data from New York City, Rhode Island, Michigan, and Italy.
Main Results:
- Successfully inferred time-dependent parameters for integer-order and time-delay models.
- Determined time-dependent fractional derivative orders for fractional differential models.
- Demonstrated the capability of PINNs to simultaneously infer unknown parameters and unobserved dynamics.
- Quantified uncertainties associated with neural network predictions and control measures.
Conclusions:
- PINNs provide a powerful framework for enhancing epidemiological modeling.
- The method allows for the identification of complex, time-varying dynamics and parameters.
- Accurate forecasting of pandemic spread, like COVID-19, is achievable with improved model identifiability and uncertainty quantification.
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