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Direct Estimation of Parameters in ODE Models Using WENDy: Weak-form Estimation of Nonlinear Dynamics.
David M Bortz1, Daniel A Messenger, Vanja Dukic
1Department of Applied Mathematics, University of Colorado, Boulder, CO 80309-0526.
The Weak-form Estimation of Nonlinear Dynamics (WENDy) method accurately estimates parameters in nonlinear ODE systems. This novel approach is robust to noise and computationally efficient, outperforming traditional methods for complex systems.
Area of Science:
- Dynamical Systems and Mathematical Biology
- Computational Science and Engineering
Background:
- Estimating parameters in nonlinear ordinary differential equation (ODE) systems is crucial for scientific modeling.
- Traditional methods often rely on numerical ODE solvers, which can be slow and inaccurate, especially for high-dimensional or stiff systems.
- Measurement noise in biological data further complicates parameter estimation.
Approach:
- Introduced the Weak-form Estimation of Nonlinear Dynamics (WENDy) method, which avoids ODE solvers by converting the system's strong form to its weak form.
- Employs an Errors-In-Variables framework and iteratively reweighted least squares for robust parameter inference.
- Utilizes orthonormal test functions derived from C-infinity bump functions for improved accuracy.
Key Points:
- WENDy provides accurate parameter estimates for nonlinear ODEs, even with significant measurement noise.
- It is computationally efficient, often outperforming traditional methods by orders of magnitude for complex and stiff systems.
- Demonstrated effectiveness across diverse models in population biology, neuroscience, and biochemistry.
Conclusions:
- WENDy offers a robust and computationally efficient alternative for parameter estimation in nonlinear dynamical systems.
- The method's performance is competitive with, and often superior to, conventional approaches.
- Open-source code is available for reproducibility and further application.
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