INDEFINITE QUADRATIC ESTIMATION AND CONTROL: A Unified Approach to H_2 and H_oo Theories B. Hassibi, A. H. Sayed, and T. Kailath Studies in Applied Mathematics, vol. 16, SIAM, PA. Hardcover. xvii+555 pages. ISBN 0-89871-411-7. Descirption: This monograph presents a unified mathematical framework for a wide range of problems in estimation and control. The authors discuss two most commonly used methodologies: the stochastic H_2 approach and the deterministic (worst- case) H_oo approach. Despite the fundamental differences in the philosophies of these two approaches, the authors have discovered that, if indefinite metric spaces are considered, they can be treated in the same way, and are essentially the same. The benefits and consequences of this unification are pursued in detail, with discussions of how to generalize well-known results from H_2 theory to the H_oo setting, as well as new results and insights, the development of new algorithms, and applications to adaptive signal processing. Table of Contents: 1. Introduction and Motivation 2. Linear Estimation in Krein Spaces 3. State-Space Models in Krein Space 4. Finite Horizon H_oo Filtering 5. Array Algorithms 6. Several Related Problems 7. H_oo Optimality of the LMS Algorithm 8. Duality 9. Finite-Horizon Control Problems 10. Input-Output Approach to H_2 and H_oo Estimation 11. Input-Output Approach to H_2 and H_oo Control 12. The Discrete-Time Algebraic Riccati Equation 13. Infinite-Horizon Results for State-Space Models 14. Asymptotic Behavior 15. Optimal H_oo Solutions 16. Continuous-Time Results and Final Remarks Bibliography Index Audience: Written for the second-year graduate student in electrical, mechanical, or aerospace engineering, the book requires a basic understanding of linear algebra and linear systems theory. Researchers in systems and control, signal processing, communications, and numerical algorithm development will also find this book useful. About the Authors: B. Hassibi is with Bell Laboratories, Murray Hill, NJ. A. H. Sayed is Associate Prof. of Electrical Eng., UCLA T. Kailath is Hitachi America Prof. of Eng., Stanford Univ.