Input: a dataset, V, including all the positive and negative samples, and the negative samples are more than the positive samples. |
Output: ensemble classifier based on integrating multiple classification instances. |
(1) For to |
(2) If is a positive sample |
(3) , is the weight of |
(4) else |
(5) |
(6) End If |
(7) End For |
(8) t is used to record the current iteration number, and its initial value is set as 1 |
(9) While () |
(10) = Null, the negative training set is emptied |
(11) If equals 1 |
(12) All negative samples are gathered into k clusters based on the -means method. Assume set P is composed of all the |
positive samples and the parameter |
(13) For each cluster, the sample locating closest to the center is selected and added into . Furthermore, the number of |
negative samples is equal to that of positive samples |
(14) else |
(15) According to the weights of negative samples, k negative samples are selected in proportion to their weights. |
These samples are added into and |
(16) End If |
(17) The training dataset is composed of and . A new classification instance based on SVM is constructed by using |
the training dataset and integrating their weight distribution |
(18) is used to classify all the samples in , evaluate its classification performance , |
and compute its classification error rate |
(19) The adjustment weight is calculated, and the weight of each positive and negative sample |
is updated by using the rule |
(20) |
(21) End While |
(22) An integrated classifier is constructed by integrating classification instances based on the voting mechanism. |
The final classification result is obtained as follows. |
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