* 1. Conference for the paper: IMS*

** Dynamical systems trajectory estimation via tunable
models with noisy data
**

Grace Wahba and Jianjian Gong

* Department of Statistics, University
of Wisconsin, Madison WI USA*

Donald R. Johnson

* Space Science and Engineering Center, University
of Wisconsin, Madison WI USA*

Joseph Tribbia

* National Center for Atmospheric Research,
Boulder CO USA*

We consider the estimation of a trajectory which
represents the evolution of a very complex dynamical system,
for which there exists an approximate computer representation
with some physical parameters only known approximately,
and for which scattered, noisy, incomplete observations
on functionals of the trajectory over
time and space are available. We consider the simultaneous
tuning of weighting, smoothing and physical parameters,
which influence the fitted trajectory.
Such problems occur in general circulation models describing the
atmosphere and the ocean, and elsewhere. Simulation results concerning
a `toy' problem based on an equivalent barotropic vorticity
equation on a latitude circle are described, and feasible
methods for potential
implementation in operational systems are discussed.

[Grace Wahba,
Dept. of Statistics, University of Wisconsin, 1210 W.
Dayton St., Madison, WI 53706, USA;
` wahba@stat.wisc.edu`]

See URL `
ftp://ftp.stat.wisc.edu/pub/wahba/talks/sydney.96`
for related work.

* 2. Oral Presentation*

* 3. This paper is invited for the IMS Session on `Curve Estimation'*

Wed Feb 21 19:08:36 CST 1996