%0 Journal Article %T An Activation Method of Topic Dictionary to Expand Training Data for Trend Rule Discovery %A Shigeaki Sakurai %A Kyoko Makino %A Shigeru Matsumoto %J Applied Computational Intelligence and Soft Computing %D 2014 %I Hindawi Publishing Corporation %R 10.1155/2014/871412 %X This paper improves a method which predicts whether evaluation objects such as companies and products are to be attractive in near future. The attractiveness is evaluated by trend rules. The trend rules represent relationships among evaluation objects, keywords, and numerical changes related to the evaluation objects. They are inductively acquired from text sequential data and numerical sequential data. The method assigns evaluation objects to the text sequential data by activating a topic dictionary. The dictionary describes keywords representing the numerical change. It can expand the amount of the training data. It is anticipated that the expansion leads to the acquisition of more valid trend rules. This paper applies the method to a task which predicts attractive stock brands based on both news headlines and stock price sequences. It shows that the method can improve the detection performance of evaluation objects through numerical experiments. 1. Introduction Recently, various kinds of sequential data are easily and cheaply collected from real world and virtual world. It is anticipated that the data includes the knowledge that brings smart life to us. Therefore, many researches aggressively tackle on the knowledge discovery task from the data [1¨C5]. On the other hand, the knowledge discovery task depends on features of the data and types of the knowledge. It is impossible to deal with all features and all types by only a method. It is indispensable to develop a discovery method reflecting target features and types. We try to develop a method which predicts whether evaluation objects such as companies and products are to be attractive in near future. This is because target data is easily collected from internet environments and it is easy for the prediction task to quantitatively evaluate the accuracy. The method deals with both text sequential data and numerical sequential data related to evaluation objects. It discovers trend rules from them. Each trend rule represents a relationship among evaluation objects, keywords, and numerical changes. The method applies the trend rules to text sequential data collected in the designated period and predicts attractive evaluation objects in the next period. It regards evaluation objects whose trends change as attractive evaluation objects. This paper aims at discovering more valid trend rules in order to improve detection performance in the prediction. It focuses on the expansion of the training data because many machine learning researches show that the expansion brings about better learning results. This %U http://www.hindawi.com/journals/acisc/2014/871412/