Natural Language Understanding Tools with Low Language Resource in Building Automatic Indonesian Mind Map Generator

Here, we describe our work in developing Indonesian Mind Map Generator that employs several Indonesian natural language understanding tools as its main engine. The Indonesian Mind Map Generator 1 aims to help the user in easily making a Mind Map object. The system consists of several Indonesian natural language understanding tools such as Indonesian POS Tagger, Indonesian Syntactic Parser, and Indonesian Semantic Analyzer. The methods used for developing each of Indonesian natural language understanding tools are devised to such an extend that they are enable to alleviate the low availability of Indonesian language resources. For Indonesian POS Tagger, we employed HMM and subsequently enhanced the result by using affix tree. As for the Indonesian Syntactic Parser, we compared the performance of CYK and Earley parser, which are known as common dynamic algorithms in PCFG. The Indonesian Semantic Analyzer consists of several components such as lexical semantic attachment, reference resolution, and Semantic Analyzer itself that transforms the parse tree result into first order logic representation. In our work, instead of using a rich resource on semantic information for each vocabulary, we defined several rules for the lexical semantic attachment based on POS Tags and certain words. Finally, to develop the Mind Map generator, we used the radial drawing method to visualize the first order logic representation and we also built a Mind Map editor to allow a user in modifying the Mind Map result. To evaluate the result, we conducted the experiments for each component mentioned previously. The POS Tagger accuracy achieved 96.5%, the Syntactic Parser achieved accuracy of 47.22%, and the Semantic Analyzer achieved accuracy of 62.5%. The final result of Mind Map object was evaluated by 5 respondents. The results of evaluationshowed that, for the simple sentence, the Mind Map object can be easily understood. 1. Background Nowadays, many education systems employ Mind Map symbols in explaining concepts that can be understood easily by the students. The idea of Mind Map is to use picture and color combination, which is compatible with how the brain works(1). Since Mind Map is a popular concept, people try to develop Mind Map editors to help the other sin drawing a Mind Map. One of the drawbacks is that, in these Mind Map editors, user has to draw the object from scratch, which can demotivate the user to start using the Mind Map editor. To handle such problems, several researches proposed a Mind Map generator tool to help the user in preparing the Mind Map object. By using a Mind Map generator tool, one doesn't have to draw the Mind Map object from scratch. User can edit the result of Mind Map generator tool and shorten the effort to draw the Mind Map object. Unfortunately, the Mind Map generator tool is only available for English text(2)(3). In English Mind Map generator, the basic approach is to employ natural language understanding tool in transforming English text into other representations such as syntactical representation or semantic representation. There was no research or product on developing Mind Map generator for Indonesian language. In the recent years, there have been several works on developing 1 The application can be accessed at http://mindmap.kataku.org