lines 2-26 of file: smoother.xrst {xrst_begin smoother} {xrst_spell nonaffine } The iterated Kalman smoother as a Gauss-Newton method ##################################################### Abstract ******** The Kalman smoother is known to be the maximum likelihood estimator when the measurement and transition functions are affine; i.e., a linear function plus a constant. A new proof of this result is presented that shows that the Kalman smoother decomposes a large least squares problem into a sequence of much smaller problems. The iterated Kalman smoother is then presented and shown to be a Gauss-Newton method for maximizing the likelihood function in the nonaffine case. The method takes advantage of the decomposition obtained with the Kalman smoother. :ref:`citation` {xrst_end smoother}