Principles of System Identification

Foreword

System Identification is an ever-present interface between the real world and the mathematical world

of models for signals and systems used in control, signal processing and systems theory. It has its

early historic roots in the work of Gauss and Bayes in the eighteenth and nineteenth century and

became an established research area in Automatic Control in the mid-1960s. The 1960s and 1970s

was a bursting time of inventing new algorithms in the area. One can notice a dip in activities in the

late 1980s when it was even suggested then to discontinue the IFAC series on symposia on System

Identification. Since then, we have seen a remarkable revival of interest in the subject. Scopus lists

over 20,000 publications in 2013 with the term “System Identification” either in the title or in

the abstract. It is natural to trace this renewed interest to the exploding access to sensor and data

information as well as to computing power.

So it is important to welcome the comprehensive and up-to-date treatment of the area in the

present book by Professor Arun K. Tangirala. The text is extensive, but the division into clear parts

will make it easy both for course work and self-studies to structure the material appropriately. The

author has in his Preface discussed how this can be done efficiently.

Mastering System Identification techniques has an element of experience, creativity and inspira-

tion, in addition to the knowledge and understanding of available techniques. In this sense, System

Identification is as much an art as a science. Therefore, I am very pleased to see that the book

contains ample reference to code, such as the MATLAB System Identification Toolbox, for illus-

tration and training. There is no better way to master the area than getting hands-on experience on

the methods applied to real data. So I encourage the readers to take these opportunities to deeper

understanding and experience and wish them an interesting and enjoyable journey with this book.

Lennart Ljung

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