mPATH: An Interactive Visualization Framework for Behavior History Masaki Ito 1 Jin Nakazawa 1 Hideyuki Tokuda 12 1 Graduate School of Media and Governance, Keio University 2 Faculty of Environmental Information, Keio University niya, jin, hxt @ht.sfc.keio.ac.jp Abstract This paper presents an interactive analysis and visual- ization framework for behavior histories, called mPATH framework. In ubiquitous computing environment, it is pos- sible to infer human activities through various sensors and accumulation of their data. Visualization of such human activities is one of the key issues in terms of memory and sharing our experiences, since it acts as a memory assist when we recall, talk about, and report what we did in the past. However, current approaches for analysis and visu- alization are designed for a specific use, and therefore can not be applied to diverse use. Our approach provides users with programmability by a visual language interface for an- alyzing and visualizing the behavior histories. The frame- work includes icons representing data sources of behavior histories, analysis filters, and viewers. By composing them, users can create their own analysis method of behavior his- tories. We also demonstrate several visualizations on the framework. The visualizations show the flexibility of creat- ing behavior history viewers on the mPATH framework. 1. Introduction In ubiquitous computing environment where computers and sensors are embedded in our surroundings and assist our life, cognition of human behavior will be possible. Today, sensing technology is one of the hottest topics for ubiqui- tous computing researchers. Various technologies for gen- erating a sensor network have developed[11][18]. By sensor networks, acquisition of information in a certain place like temperature, humidity, noise level and light level is realized. In addition, tracking an object are also enabled by the coor- dination of sensors. Technologies for mobile computing[5][1][6] are also useful to sense our activities and environmental informa- tion. Sensors equipped with a mobile device acquire various information of the user such as a location, movement orien- tation and a physiological status by alone or coordination with infrastructures in surroundings[21][16]. Inferring highly abstracted behavior of a user and creat- ing predictive model of user’s behavior from the sensed data are also hot challenges in ubiquitous computing research. There are many researches which aim to guess user’s con- text and provide adaptive services. Several context process- ing technologies are proposed for the purpose[23][22]. In addition to processing sensor data in a certain time, storing and utilizing an accumulation of behavior data brings us a possibility to develop new applications[2]. A well presented behavior history helps human activities in terms of memory and sharing our experiences since it acts as a memory assist when we recall, talk about, and report what we did in the past[17][13]. For example, displaying user’s shopping log reminds him or her of goods which he or she intended to buy, and helps explanation of his or her inten- tion of shopping to his or her company. Analysis techniques of behavior history are important to find useful information from it. There are already various proposed methods for analyz- ing accumulated behavior history. However these methods are designed for a specific use, and hence users may not acquire applicable information. The analysis method of be- havior history, therefore, should be flexible enough to find various information from behavior history. In this paper, we presents a programmable analysis and visualization framework for behavior histories, called mPATH framework. In the mPATH framework, analysis methods are modularized and we can create various analysis methods using visual programming language. The frame- work allow every developers and users to mine behavior history intuitively and flexibly. This paper is organized as follows. In the next sec- tion, we argue problems of visualization of behavior his- tory. In section 3, we introduce mPATH frameworkwhich realizes flexible analysis of behavior history using visual language. We also introduce several visualizations on the mPATH framework in section 4. We evaluate the frame- work in section 5 and introduce related works in section 6. In the final session, we conclude this paper. 2. Visualization of Behavior History In this paper, behavior history is an aggregated form of information which contains location, date and description of behavior about a certain person. Location track data obtained by a GPS receiver is an example of the behavior history. A digital photo image is also behavior history if it contains a time stamp and a location information as its Proceedings of the 19th International Conference on Advanced Information Networking and Applications (AINA’05) 1550-445X/05 $20.00 © 2005 IEEE