this paper generated a challenging two-dimensional imbalanced dataset M_DATA2 based on the normal distribution. Its scatter plot is shown in Figure 1. The dataset has a sample size of 1000, 2 feature variables, and the ratio between the number of samples in the two classes is 1:4. Among them, the samples of the minority class are divided into four parts by the majorityclasssamples, and there is a certain mixed area, which makes it difficult for the GNB classifier to classify effectivel