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The paper has proposed a linear unsupervised transfer learning (LUTL). Therefore, a cost function has been introduced. In the cost function of the proposed LUTL, the aim is to minimize the difference between the distribution of the transformed source domain (SD) data and the distribution of the target domain (TD) data. In the proposed cost function, it is also targeted to preserve the local structures of the untransformed SD data. Three mechanisms have been proposed for the preservation of local structures in the untransformed SD data: (1) minimization of the distances between the data pairs that are similar to each other in the untransformed SD data, (2) preservation of the clusters emerged in the untransformed SD data and finally (3) their combination. The optimization problem has emerged as a nonlinear one. Two techniques have been introduced to obtain an approximation of the optimal weight matrix. Each technique guarantees to reach a local optimum, but no one guarantees to reach the global solution. While the first method is an iterative one, the second is a relaxed version of the optimization problem. The paper shows also experimentally that the proposed techniques overshadow the state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Abundant data of the patients is recorded within the health care system. During data mining process, we can achieve useful knowledge and hidden patterns within the data and consequently we will discover the meaningful knowledge. The discovered knowledge can be used by physicians and managers of health care to improve the quality of their services and to reduce the number of their medical errors. Since by the usage of a single data mining algorithm, it is difficult to diagnose or predict diseases, therefore in this research, we take a combination of the advantages of some algorithms in order to achieve better results in terms of efficiency. Most of standard learning algorithms have been designed for balanced data (the data with the same frequency of samples in each class), where the cost of wrong classification is the same within all classes. These algorithms cannot properly represent data distribution characteristics when datasets are imbalanced. In some cases, the cost of wrong classification can be very high in a sample of a special class, such as wrongly misclassifying cancerous individuals or patients as healthy ones. In this article, it is tried to present a fast and efficient way to learn from imbalanced data. This method is more suitable for learning from the imbalanced data having very little data in class of minority. Experiments show that the proposed method has more efficiency compared to traditional simple algorithms of machine learning, as well as several special-to-imbalanced-data learning algorithms. In addition, this method has lower computational complexity and faster implementation time. [ABSTRACT FROM AUTHOR]