Page 138 - Introduction to Statistical Pattern Recognition
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120                        Introduction to Statistical Pattern Recognition



                      Problems


                      1.   Two one-dimensional distributions are uniform in [0, 21  for 01  and [ 1, 41
                           for q, and PI = P2 = 0.5.

                           (a)   Find  the  Bayes  boundary  for  minimum  error,  and  compute  the
                                Bayes error.
                           (b)   Plot the operating characteristics.
                           (c)   Find the Neyrnan-Pearson boundary with   = 0.25.
                           (d)  Find the minimax boundary.

                           (e)   Compute the Chernoff bound, and find the optimal s.
                           (f)  Compute the Bhattacharyya bound.
                      2.   Two normal distributions are characterized by
                                                Pi =P2 =0.5,






                           (a)   Draw the Bayes decision boundary to minimize the probability of
                                error.

                           (b)   Draw  the  Bayes  decision  boundary  to  minimize  the  cost  with
                                cII =~~~=Oandc~~=2c~,.
                      3.   Repeat Problem 2 for





                      4.   Assuming that  c II  = c22 = 0 and  c 12 =c21 in  Problem  2,  plot  the  rela-
                           tionship between the threshold values of the likelihood ratio and the pro-
                           babilities of errors.
                           (a)   Plot the operating characteristics.
                           (b)  Find  the  total  error when  the  Neyman-Pearson  test  is  performed
                                with E] = 0.05.
                           (c)   Find the threshold value and the total error for the minimax test.
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