Our purposes in writing this Second Edition | more than a quarter century after
the original | remain the same: to give a systematic account of the major
topics in pattern recognition, based whenever possible on fundamental principles. We
believe that this provides the required foundation for solving problems in more specialized
application areas such as speech recognition, optical character recognition,
signal analysis, and so on. Since 1973, there has been an immense wealth of e®ort,
and in many cases progress, on the topics we addressed in the First Edition. The
pace of progress in algorithms for learning and pattern recognition has been exceeded
only by the improvements in computer hardware. Some of the outstanding problems
acknowledged in the First Edition have been solved, whereas others remain as frustrating
as ever. Taken with the manifest usefulness of pattern recognition, this makes
the ¯eld extremely vigorous and exciting.
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