Page 261 - Introduction to Statistical Pattern Recognition
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5  Parameter Estimation                                       243





                                E*


                                EX



                                                                              (5.174)


                   where Ex indicates the expectation with respect to the w's.
                            AX ,*
                        f(X, M, ,X, can be expanded around f(X,k,,i,) by the Taylor series as
                                 )





                                               A*   A
                   where  AM;  = My  - k;, A$  = Z;  -Xi.  and  df*/&;  is  defined  in  (5.141).
                   Since h(~) =f(~,M~,i,) -f(~,ii*,i*),


                   Ah(X) = h*(X) - h(X)


                                                                              (5.176)


                   The partial derivatives of (5.176) can be obtained by (5.144) and (5.145).

                   Bootstrap Expectation

                        Using the approximation of (5.60), (5.169) can be approximated as


                                                                              (5.177)


                   The  third  term  is  a  third  order  variation  with  the  combination  of  AwY)  and
                     -2
                   Ah  , and can be ignored.  Thus, our analysis will focus on the first and second
                   terms only.  With  this  in  mind,  substituting (5.171), (5.172),  and  (5.176) into
                   (5.177) produces
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