Zhejiang Gongshang University

About: Zhejiang Gongshang University is a education organization based out in Hangzhou, China. It is known for research contribution in the topics: Computer science & Chemistry. The organization has 8258 authors who have published 7670 publications receiving 90296 citations. The organization is also known as: Zhèjiāng Gōngshāng Dàxué.

Weighted support vector machine for classification with uneven training class sizes

Abstract: In the standard support vector machines for classification, training sets with uneven class sizes results in classification biases towards the class with the large training size. That is to say, the larger the training sample size for one class is, the smaller its corresponding classification error rate is, while the smaller the sample size, the larger the classification error rate. The main causes lie in that the penalty of misclassification for each training sample is considered equally. Weighted support vector machines for classification are proposed in this paper where penalty of misclassification for each training sample is different. By setting the equal penalty for the training samples belonging to same class, and setting the ratio of penalties for different classes to the inverse ratio of the training class sizes, the obtained weighted support vector machines compensate for the undesirable effects caused by the uneven training class size, and the classification accuracy for the class with small training size is improved. Experimental simulations on breast cancer diagnosis show the effectiveness of the proposed methods.

Effect of Migration on Children's Educational Performance in Rural China

Abstract: Migration is one of the main ways of alleviating poverty in developing countries, including China. However, there are concerns about the potential negative effects of migration on the educational achievement of the children that are left behind in villages when one or both of their parents out-migrate to cities. This paper examines changes in school performance before and after the parents of students out-migrate. Surprisingly, we find that there is no significant negative effect of migration on school performance. In fact, we find that educational performance improves in migrant households in which the father out-migrates.