On Segmentation of Time Series.
Abstract
The problem of partitioning a time-series into segments is considered. The segments fall into classes, which may correspond to phases of a cycle (recession, recovery, expansion in the business cycle) or to portions of a signal obtained by scanning (background/clutter, target, background/clutter again, another target, etc.; or normal tissue, tumor, normal tissue). Parametric families of distributions are considered, a set of parameter values being associated with each class. With each observation is associated an unobservable label, indicating from which class the observation arose. The label process is modeled as a Markov chain. Segmentation algorithms are obtained by applying a method of iterated maximum likelihood to the resulting likelihood function. In this paper special attention is given to the situation in which the observations are conditionally independent, given the labels. A numerical example is given. Choice of the number of classes, using Akaike's automatic (model) identification criterion (AIC), is illustrated. Prediction is considered. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 30, 1981
- Accession Number
- ADA109479
Entities
People
- Stanley L. Sclove
Organizations
- University of Illinois at Chicago