| dc.description.abstract | In a world full of information, more and more companies want to use this information to improve their competitiveness. However, the problems of “Class Imbalance” and “Missing Value” have always been important issues in the real world. For example, class imbalance datasets often occur in different fields such as medical diagnosis and bankruptcy prediction. In class imbalance, the number of samples of the majority class in the dataset is larger than that of the minority class, and the data will look skewed. In order to have a higher classification accuracy rate, the prediction model established by the general classifier will also be misjudged as a large class of data due to the influence of the skewed distribution. If the precious minority class contains some missing data, the available data are even rarer.
In this thesis, dynamic time warping is used as the core for the missing value imputation task. Dynamic time warping correction feature is used to solve the problem of missing data in the minority class containing small numbers of samples. And this method is not limited to the need for a complete data sample. Therefore, in the experiment, 10%, 30%, 50%, 70%, and 90% missing rates of the minority class data are simulated.
In this paper, we use 17 KEEL datasets for the experiment, and two classification models (SVM, Decision Tree) are constructed, and the AUC (Area Under Curve) are examined for different methods. The experimental results show that the dynamic time warping has good performance under the missing rate of 50%~90%, which performs better than the KNN imputation method. | en_US |