Page 224 - Introduction to Statistical Pattern Recognition
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206                        Introduction to Statistical Pattern Recognition


                           Quadratic classifier: Although we  do not  need  to know  the value  of  v
                      to  conduct  Experiment  3  to  estimate  E, v  can  be  computed  by  obtaining  the
                      partial  derivatives of  h  and  carrying  through  the  integration  of  (5.69)  for  a
                      specific classifier.  When the quadratic classifier of  (5.54) with  the parameters
                      of  (5.8) and  (5.9)  is  adopted,  the  partial  derivatives  of  h  are,  from  (A.29)-
                      (A.32) and (A.36)-(A.38),

                      --                                                          (5.72)
                       " - (-l)rA;'(X-A4r),
                       aM,.

                                                                                  (5.73)



                                                                                  (5.74)









                      Substituting  (5.72)-(5.75)  into  (5.70),  and  noting  that  1:" = 1,  hj2' = h- I+
                      mil) = 0 and mj2' = m,, v of (5.71) becomes
                                     1
                                     2x
                                vy = -Jkq(X,  o)ej""'X'p(x)dodX ,                 (5.76)
                      where
                                           If {          }
                                   1
                         fJX,  0) = -  (n+l)C .,f  -
                                   2
                                          I=I







                      The integration of  (5.76) can be carried out by  using the procedure discussed in
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