著者

藤巻 遼平 広瀬 俊亮 中田 貴之

出版者

The Japanese Society for Artificial Intelligence

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.25, no.4, pp.540-548, 2010

被引用文献数

1 1

---

Although Subsequence Time Series (STS) clustering has been one of the most popular techniques to extract typical subsequence patterns from time-series data, previous studies have gave surprising reports that cluster centers obtained using STS clustering closely resemble ``sine waves'' with little relation to input time-series data. This means that STS clustering cannot be used for its original purpose, extraction of typical subsequences. Despite this serious fact, its mathematical structure has seldom been studied. The main contribution of this paper is that we give a theoretical analysis of STS clustering from a frequency-analysis viewpoint and identify that sine waves are generated due to the superposition of time series subsequences, which have the same spectra but different phases. Another contribution is that we propose a clustering algorithm, which uses a phase alignment preprocessing, to avoid sine-wave patterns.

著者

大島 直樹 山口 雄大 デシルバ ラビンドラ 岡田 美智男

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.29, no.3, pp.288-300, 2014-05-01 (Released:2014-04-04)

参考文献数

17

---

Understanding why people treat simple geometric animations like real agent which has intention to interact with people even if its geometry is artificial thing will aid the `agency' problems of human-agent interaction. This paper explores effects of treating simple geometric animations as a real participant to facilitate multi-party conversation in social interaction. Observational study was conducted with groups of two or three persons using simple circle (sociable spotlight) which moves based on dynamic information in the current multi-party conversation, with the goal of discovering how participants are utilizing the behaviors of sociable spotlight as an other party for organizing the conversational sequences in talk-in-interaction. In addition, we motivated to explore how the sociable spotlight is embedded within the organization of conversation and how the user's behaviors are changed according to the sociable spotlight's behaviors by investigate through conversation analysis of a video-recording. Finally, we conclude how the agency of artificial things constructed in multi-party conversation from minimal designing point of view.

著者

長谷川 貴之 鍜治 伸裕 吉永 直樹 豊田 正史

出版者

The Japanese Society for Artificial Intelligence

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.29, no.1, pp.90-99, 2014

被引用文献数

1

---

While there have been many attempts to estimate the emotion of a speaker from her/his utterance, few studies have explored how her/his utterance affects the emotion of the listener. This has motivated us to investigate two novel tasks: predicting the emotion of the listener and generating a response that evokes a specific emotion in the listeners mind. We target Japanese Twitter posts as a source of dialogue data and automatically build training data for learning the predictors and generators. The feasibility of our approaches is assessed by using 1099 utterance-response pairs that are built by five human workers.

著者

稲葉 通将 神園 彩香 高橋 健一

出版者

The Japanese Society for Artificial Intelligence

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.29, no.1, pp.21-31, 2014

被引用文献数

9

---

Recently, computerized dialogue systems are studied actively. Non-task-oriented dialogue systems that handle domain-free dialogues like chats are expected be applied in various fields, but many challenges still exist in developing them. This paper addresses the problem of utterance generation for non-task-oriented dialogue systems. We search twitter data by topic words and acquire sentences. The sentences are filtered by rules and scored on the basis of training data. We acquire the sentences which have a high score as utterances. The results of an experiment demonstrate that the proposed method can generate appropriate utterances with a high degree of accuracy.

著者

杉山 貴昭 駒谷 和範 佐藤 理史

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.29, no.1, pp.32-40, 2014-01-05 (Released:2014-01-07)

参考文献数

16

被引用文献数

2 1

---

We have tackled a novel problem of predicting when a user is likely to begin speaking to a humanoid robot. The generality of the prediction model should be examined to apply it to various users. We show in this paper that the following two empirical evaluations. First, our proposed model does not depend on the specific participants whose data were used in our previous experiment. Second, the model can handle variations caused by individuality and instruction. We collect a data set to which 25 human participants give labels, indicating whether or not they would be likely to begin speaking to the robot. We then train a new model with the collected data and verify its performance by cross validation and open tests. We also investigate relationship of how much each human participant felt possible to begin speaking with a model parameter and instruction given to them. This shows a possibility of our model to handle such variations.

著者

松永 健太 山田 健太 高安 秀樹 高安 美佐子

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.27, no.6, pp.365-375, 2012 (Released:2012-09-27)

参考文献数

27

被引用文献数

2

---

The dealer model is an agent based model that simulates the simplified dealer's behavior and satisfies various empirical laws of the foreign exchange markets by tuning major three parameters. In this study,we improve the dealer model to satisfy a newly established empirical law about widening of spread as a response to big market price changes. As a result when a big news occurs and the market becomes turbulent, this new model can reproduce broadening of distribution of price change.In a peculiar price change of official intervention in the foreign exchange market by Bank of Japan, this model can be used for estimation of strategies of intervention and responses of the market.

著者

杉原 貴彦 劉 欣 村田 剛志

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.28, no.1, pp.67-76, 2013 (Released:2013-01-05)

参考文献数

18

被引用文献数

2

---

Many real-world complex systems can be modeled as networks, and most of them exhibit community structures. Community detection from networks is one of the important topics in link mining. In order to evaluate the goodness of detected communities, Newman modularity is widely used. In real world, however, many complex systems can be modeled as signed networks composed of positive and negative edges. Community detection from signed networks is not an easy task, because the conventional detection methods for normal networks cannot be applied directly. In this paper, we extend Newman modularity for signed networks. We also propose a method for optimizing our modularity, which is an efficient hierarchical agglomeration algorithm for detecting communities from signed networks. Our method enables us to detect communities from large scale real-world signed networks which represent relationship between users on websites such as Wikipedia, Slashdot and Epinions.

著者

山本 修身 佐藤根 寛

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.26, no.2, pp.419-426, 2011

---

The fifteen puzzle is a sliding puzzle which has fifteen pieces on which numbers from 1 to 15 are printed. Using the IDA* algorithm with an admissible evaluation function, we can obtain an optimal solution of the puzzle. The performance of the algorithm depends on the evaluation function. The most simple evaluation function is the Manhattan evaluation function, whose value is the sum of the Manhattan distances from the positions of the corresponding pieces in the goal configuration. In this paper, we propose an evaluation function whose values are greater than or equal to that of the Manhattan evaluation function. Our evaluation function refers an approximated database of the gap-2<i>n</i> set. The database is computed beforehand like pattern databases, but it is completely different from pattern databases. The belongingness of a configuration of pieces to the set has to be checked by the database. Using an evaluation function based on the gap-8 set, we were able to reduce the number of search nodes to about 2.5×10^-4 times in average with the IDA* algorithm compared with the Manhattan evaluation function. We also show that combining an evaluation function by gap-8 set and an evaluation function by additive pattern databases of disjoint seven and eight pieces, we were able to reduce the number of search nodes by about 53 compared with the evaluation function only by the additive pattern databases.

著者

鳥海 不二夫 石井 健一郎

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.27, no.6, pp.346-354, 2012 (Released:2012-10-03)

参考文献数

12

被引用文献数

1

---

The concept of the ``wisdom of crowds'' has attracted attention for finding new insights by appropriately processing the large amount of information possessed by crowds. A prediction market is one estimating method that uses the mechanisms of financial markets such as stock or exchange markets to realize the ``wisdom of crowds''. In this study, we use agent-based simulation to clarify the condition that makes prediction markets effective. An artificial market is a virtual financial market run on a computer. Agents participate in them as computer programs that play the role of virtual dealers. In the simulation, we confirm the influence of the following parameters: information transmission frequency, the retention of motivation, and the gap of information recieve abilities. The results of this study suggest that prediction markets realize more accurate results than opinion polls under the following conditions: the gap of information recieve abilities and relatively low motivation.

著者

石下 円香 佐藤 充 森 辰則

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.24, no.4, pp.339-350, 2009 (Released:2009-05-22)

参考文献数

15

被引用文献数

2

---

In this paper, we propose a method of non-factoid Web question-answering that can uniformly deal with any class of Japanese non-factoid question by using a large number of example Q&A pairs. Instead of preparing classes of questions beforehand, the method retrieves already asked question examples similar to a submitted question from a set of Q&A pairs. Then, instead of preparing clue expressions for the writing style of answers according to each question class beforehand, it dynamically extracts clue expressions from the answer examples corresponding to the retrieved question examples. This clue expression information is combined with topical content information from the question to extract appropriate answer candidates. The score of an answer candidate is measured by the density of submitted question's keywords, words associated with the question and the clue expressions. Note that we utilize the set of Q&A pairs, not to find answers from them, but to obtain clue expressions about the writing style of their answers. The information source for question answering is the Web documents retrieved by using an API of a Web search engine. Experimental results showed that the clue expressions obtained from the set of examples improved the accuracy of answer candidate extraction.

著者

市野 順子 田野 俊一

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.25, no.3, pp.504-513, 2010 (Released:2010-04-13)

参考文献数

39

被引用文献数

1

---

In this study, we investigated the relationship between phases of meeting and non-verbal speech information. We considered that conversations at the meeting must show information to phases of the meeting as non-verbal features. We attempted to discriminate between the divergence phase and the convergence phase by the decision tree method using only non-verbal speech information. We performed an experiment with a group task based on a modification of the game Twenty-Questions and recorded participants' speech data. In a discrimination test, we used the recorded speech, and defined non-verbal speech features such as switching pauses (i.e. silent intervals between the utterance of two speakers), frequency for each turn-taking pattern and duration. We conducted the two discrimination tests for using parameters with friends group, with strangers group and with both groups. From the results, the accuracy of the open test is 77.3%, 85.2% and 77.3%, respectively. Taking into account only non-verbal speech information was used, we consider these results to be fairly good.

著者

竹内 誉羽 庄野 修 辻野 広司

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.27, no.2, pp.92-102, 2012 (Released:2012-02-10)

参考文献数

23

---

Future robots/agents will perform situated behaviors for each user. Flexible behavioral learning is required for coping with diverse and unexpected users' situations. Unexpected situations are usually not tractable for machine learning systems that are designed for pre-defined problems. In order to realize such a flexible learning system, we were trying to create a learning model that can function in several different kinds of state transitions without specific adjustments for each transition as a first step. We constructed a modular neural network model based on reinforcement learning. We expected that combining a modular architecture with neural networks could accelerate the learning speed of neural networks. The inputs of our neural network model always include not only observed states but also memory information for any transition. In pure Markov decision processes, memory information is not necessary, rather it can lead to lower performance. On the other hand, partially observable conditions require memory information to select proper actions. We demonstrated that the new learning model could actually learn those multiple kinds of state transitions with the same architectures and parameters, and without pre-designed models of environments. This paper describes the performances of constructed models using probabilistically fluctuated Markov decision processes including partially observable conditions. In the test transitions, the observed state probabilistically fluctuated. The new learning model could function in those complex transitions. In addition, the learning speeds of our model are comparable to a reinforcement learning algorithm implemented with a pre-defined and optimized table-representation of states.

著者

後藤 真孝 緒方 淳 江渡 浩一郎

出版者

The Japanese Society for Artificial Intelligence

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.25, no.1, pp.104-113, 2010

被引用文献数

2 1

---

In this paper, we describe a public web service, <EM>``PodCastle''</EM>, that provides full-text searching of speech data (Japanese podcasts) on the basis of automatic speech recognition technologies. This is an instance of our research approach, <EM>``Speech Recognition Research 2.0''</EM>, which is aimed at providing users with a web service based on Web 2.0 so that they can experience state-of-the-art speech recognition performance, and at promoting speech recognition technologies in cooperation with anonymous users. PodCastle enables users to find podcasts that include a search term, read full texts of their recognition results, and easily correct recognition errors by simply selecting from a list of candidates. Even if a state-of-the-art speech recognizer is used to recognize podcasts on the web, a number of errors will naturally occur. PodCastle therefore encourages users to cooperate by correcting these errors so that those podcasts can be searched more reliably. Furthermore, using the resulting corrections to train the speech recognizer, it implements a mechanism whereby the speech recognition performance is gradually improved. Our experience with this web service showed that user contributions we collected actually improved the performance of PodCastle.

著者

山田 誠二 村瀬 文彦

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.16, no.1, pp.46-54, 2001 (Released:2002-02-28)

参考文献数

12

---

In this paper, we develop an organization method of page information agents for adaptive interface between a user and a Web search engine. Though a Web search engine indicates a hit list of Web pages to user’s query using a large database, they includes many useless ones. Thus a user has to select useful Web pages from them with page information indicated on the hit list, and actually fetch the Web page for investigating the relevance. Unfortunately, since the page information on a hit list is neither sufficient nor necessary for a user, the adequate information is necessary for valid selection. However which information is adequate depends on a user and a task. Hence we propose adaptive interface AOAI in which different page information agents are organized through man-machine interaction. In AOAI, the page information agents indicating different page information on a hit list like the file-size, network traffic and a page title are prepared at first. A user evaluates them through searching with a search engine, and the agents are organized based on the evaluation. As results, different organizations are achieved depending on a user and a task. Finally we make experiments with subjects and find out AOAI is promising for adaptive interface between a user and a search engine.

著者

飯島 勝矢 亀山 祐美 秋下 雅弘 大内 尉義 柳元 伸太郎 今井 靖 矢作 直樹 ロペズ ギヨーム 酒造 正樹 山田 一郎

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.27, no.2, pp.40-45, 2012 (Released:2012-02-01)

参考文献数

7

被引用文献数

1 1

---

An increase in short-term blood pressure (BP) variability is a characteristic feature in the elderly. It makes the management of hemodynamics more difficult, because it is frequently seen disturbed baro-reflex function and increased arterial stiffness, leading to isolated systolic hypertension. Large BP variability aggravates hypertensive target organ damage and is an independent risk factor for the cardiovascular (CV) events in elderly hypertensive patients. Therefore, appropriate control in BP is indispensable to manage lifestyle-related diseases and to prevent subsequent CV events. In addition, accumulating recent reports show that excessive BP variability is also associated with a decline in cognitive function and fall in the elderly. In the clinical settings, we usually evaluate their health condition, mainly with single point BP measurement using cuff inflation. However, unfortunately we are not able to find the close changes in BP by the traditional way. Here, we can show our advantageous approach of continuous BP monitoring using newly developing device `wearable BP sensing' without a cuff stress in the elderly. The new device could reflect systolic BP and its detailed changes, in consistent with cuff-based BP measurement. Our new challenge suggests new possibility of its clinical application with high accuracy.

著者

西山 莉紗 竹内 広宜 渡辺 日出雄 那須川 哲哉

出版者

The Japanese Society for Artificial Intelligence

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.24, no.6, pp.541-548, 2009

被引用文献数

1 2

---

It is important for R&D managers, consultants, and other people seeking broad knowledge in technology fields to survey technical literature such as research papers, white papers, and technology news articles. One of the important kinds of information for those people regards the effectiveness of new technologies in their own businesses. General search engines are good at selecting documents revealing the details of a specific technology or a technology field, but it is hard to obtain useful information about how a technology will apply to individual business cases from such search results. There is a need for a technology survey assistance tool that helps users find technologies with suitable capabilities. In this paper, two technical tasks were tackled to develop the prototype of this assistance tool: Extraction of advantage phrases and scoring for the advantage phrases to find novel applications in the target technology field. We describe a new method to identify advantage phrases in technical documents and our scoring function that gives higher scores to novel applications of the technology. The results of evaluations showed our phrase identification method with only a few phrasal patterns performs almost as well as human annotators, and the proposed scoring conforms better to the decisions made by professionals than random sort.

著者

石垣 司 竹中 毅 本村 陽一

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.26, no.6, pp.670-681, 2011 (Released:2011-10-12)

参考文献数

48

被引用文献数

8 13

---

This paper describes a computational customer behavior modeling by Bayesian network with an appropriate category. Categories are generated by a heterogeneous data fusion using an ID-POS data and customer's questionnaire responses with respect to their lifestyle. We propose a latent class model that is an extension of PLSI model. In the proposed model, customers and items are classified probabilistically into some latent lifestyle categories and latent item category. We show that the performance of the proposed model is superior to that of the k-means and PLSI in terms of category mining. We produce a Bayesian network model including the customer and item categories, situations and conditions of purchases. Based on that network structure, we can systematically identify useful knowledge for use in sustainable services. In the retail service, knowledge management with point of sales data mining is integral to maintaining and improving productivity. This method provides useful knowledge based on the ID-POS data for efficient customer relationship management and can be applicable for other service industries. This method is applicable for marketing support, service modeling, and decision making in various business fields, including retail services.

著者

木村 泰知 渋木 英潔 高丸 圭一 乙武 北斗 小林 哲郎 森 辰則

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.26, no.5, pp.580-593, 2011 (Released:2011-07-20)

参考文献数

14

被引用文献数

3

---

This paper presents an automatic question generation method for a local councilor search system. Our purpose is to provide residents with information about local council activities in an easy-to-understand manner. Our designed system creates a decision tree with leaves that correspond to local councilors in order to clarify the differences in the activities of local councilors using local council minutes as the source. Moreover, our system generates questions for selecting the next branch at each condition in the decision tree. We confirmed experimentally that these questions are appropriate for the selection of branches in the decision tree.

著者

片柳 亮太 菅原 俊治

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.26, no.1, pp.76-85, 2011 (Released:2011-01-06)

参考文献数

8

被引用文献数

1

---

We propose an effective method of dynamic reorganization using reinforcement learning for the team formation in multi-agent systems (MAS). A task in MAS usually consists of a number of subtasks that require their own resources, and it has to be processed in the appropriate team whose agents have the sufficient resources. The resources required for tasks are often unknown \ extit{a priori} and it is also unknown whether their organization is appropriate to form teams for the given tasks or not. Therefore, their organization should be adopted according to the environment where agents are deployed. In this paper, we investigated how the structures of network and the number of tasks affect team formations of the agents. We will show that the utility and the success of the team formation is deeply affected by depth of the tree structure and number of tasks.

著者

加藤 昇平 鈴木 祐太 小林 朗子 小島 敏昭 伊藤 英則 本間 昭

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.26, no.2, pp.347-352, 2011 (Released:2011-01-06)

参考文献数

15

被引用文献数

3 3

---

This paper presents a new trial approach to early detection of cognitive impairment in the elderly with the use of speech sound analysis and multivariate statistical technique. In this paper, we focus on the prosodic features from speech sound. Japanese 115 subjects (32 males and 83 females between ages of 38 and 99) participated in this study. We collected speech sound in a few segments of dialogue of HDS-R examination. The segments corresponds to speech sound that is answering for questions on time orientation and number backward count. Firstly, 130 prosodic features have been extracted from each of the speech sounds. These prosodic features consist of spectral and pitch features (53), formant features (56), intensity features (19), and speech rate and response time (2). Secondly, these features are refined by principal component analysis and/or feature selection. Lastly, we have calculated speech prosody-based cognitive impairment rating (SPCIR) by multiple linear regression analysis. The results indicated that there is moderately significant correlation between HDS-R score and synthesis of several selected prosodic features. Consequently, adjusted coefficient of determination R2=0.50 suggests that prosody-based speech sound analysis has possibility to screen the elderly with cognitive impairment.