Page 26 - Introduction to Statistical Pattern Recognition
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8                          Introduction to Statistical Pattern Recognition






                                                                 SEARCH FOR
                                       NORMALIZATION             NEW MEASUREMENTS
                                       REGISTRATION


                                      (NONPARAMETRIC)
                                                                              1
                      NONPARAMETRIC            &< Eo        ERROR ESTIMATION
                      PROCESS                               (NONPARAMETRIC)




                                                            STATISTICAL TESTS

                                                            LINEAR CLASSIFIER
                                                            QUADRATIC CLASSIFIER
                                                            PIECEWISE CLASSIFIER
                      PARAMETERIZATION                      NONPARAMETRIC CLASS1  FI E R
                      PROCESS












                                             t
                               Fig. 1-6  A flow chart of the process of classifier design.

                      merely  increase the  classification error.  Therefore,  we  must  go  back  to  data
                      gathering and seek better measurements.
                           Only  when  the  estimate  of  the  Bayes  error  is  less  than  E,,,  may  we
                      proceed  to  the  next  stage  of  data  structure  analysis  in  which  we  study  the
                      characteristics of  the data.  All kinds of  data analysis techniques are used here
                      which  include feature extraction, clustering, statistical tests,  modeling, and  so
                      on.  Note that, each time a feature set is chosen, the Bayes error in the feature
                      space is estimated and compared with the one in the measurement space.  The
                      difference between them  indicates how much  classification information is  lost
                      in the feature selection process.
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