The Institute of Statistical Mathematics aims to further develop statistics by promoting the exchange of data and resources between domestic and foreign researchers. This has been examined from a statistical viewpoint, which suggests using a new index whereby the progress and effectiveness of the joint use can be objectively assessed. We analyzed co-author information using betweenness centrality in articles written by researchers at the Institute of Statistical Mathematics in 2013, obtained from the Web of Science. The analysis results enable identification of the researched people that are in the center of their research field.

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Capital adequacy ratio is widely discussed among the banking institution as they must secure certain amount as required by financial regulator. It represents the percentage of risk-weighted asset and act as the indication of no excess leverage should be hold by them. Therefore the Basel Committee has designed Basel l, Basel ll and Basel lll for banking institution as a reference to ensure the capital requirement is sufficient in minimizing the operational risk. This study aims to analyze the trend and pattern on capital adequacy and its execution in banking system in Japan after the introduction of Basel Standard. The study covered the 11 years articles published in Nikkei 21 from 2004 to 2014 by using text mining and correspondence analysis as a methodology. RMeCab and MeCab in R statistical tools were used and it leads to present the importance of Basel Standard as guidance in determining the level of capital adequacy ratio.

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Companies endeavor to manage corporate scandals, but cannot always recover from the downturns. The present paper aims to reveal the fundamental structure behind the lagged impact of a corporate scandal on its sales decline, and to identify systemic causes of management failures. To this end, a Systems Dynamics model is developed and simulated using data presented in a White Paper on the National Lifestyle 2008 published in Japan. The results show that corporate scandals are more difficult to manage when the scandal is followed by a temporal improvement without recognizing the steeper customer turnover induced by the time delay. Appropriate reactions to a corporate scandal are indispensable for prompt recovery, but their forms depend on the severity of the initial impact of the scandal. In cases of limited initial impact, no reaction may yield a more desirable result than taking some form of action. This implies that an overreaction to a small corporate scandal may ultimately accelerate the sales decline. Ethical issues aside, this fact may cause intentional concealment of corporate scandals.

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This study shows a process of designing and comparing two quantitative evaluation methods for the structure of assurance cases (AC), which use two description methods: Goal Structuring Notation, and Dependability Cases. The International Organization for Standardization has mandated organizations to include AC in ISO 26262 and recommended to include AC in other standards. This study proposes two quantitative evaluation methods designed by authors, and assesses the necessity and effectiveness of the methods based on the results of quantitative evaluation of AC to confirm if the methods are useful for work improvement. We used a questionnaire completed by third party employees who are 1) working in an organization with written work procedures developed in Japanese organizational culture, 2) working in the manufacturing industry, and 3) engaged in daily routine work. These conditions define how written work procedures and documents have been created at each participant's workplace. Since we use these written materials as evidence to evaluate ACs, they satisfy certain conditions for preparation of the written information. After showing previous research on assurance cases and presenting a procedure of quantitative evaluation, we propose two equations for quantitatively evaluating a sub-goal. One equation simply integrates the numbers of Evidence and Monitoring. The second equation takes into account users' opinion on Evidence and Monitoring to quantitatively evaluate an optional sub-goal. We then describe and discuss the results of a questionnaire on the two quantitative evaluation methods for assurance cases, one using Eq. 1 and the other using Eq. 2. Responses were given quantitatively on a seven-point ordinal scale and qualitatively in a free descriptive space. We then assessed effectiveness and necessity of the two methods. The results were statistically significant for both "effectiveness" and "necessity," And we found that Eq.1 suggested more efficacy than Eq.2. This paper concludes with future research topics.

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We consider the following problem:
1) There are demand points and possible construction sites in an urban area with some barriers. We adopt rectilinear distance.
2) We construct two facilities, one is welcome facility and the other obnoxious one. We call welcome one as A and obnoxious one as B and two facilities A, B can be constructed at the same site or constructed separately, that is, at two different sites. We assume that each construction cost of A, B is a random variable respectively and construction cost of both facilities simultaneously as a same site is also random variable. These are distributed according to normal distributions.
3) The probability that total construction cost become below budget f should be not less than thefixed probability levelα and f should be minimized.
4) We consider three criteria, that is, maximum distance from the construction site of A to all demand points to be minimized, minimum distance from the construction site of B to all demand points to be maximized and budget to be minimized.
Since usually there exists no site optimizing three criteria at a time, we seek non-dominated solutionafter definition of non-domination. Finally we conclude results and discuss further research problems.

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Utilizing both qualitative and quantitative analyses, this article intended to analyze (1) whether a special article inserted in the Indian Patent Law 2005 had a role in reducing the negative impact on the Indian Pharmaceutical Industry from the introduction of product patents based on analysis of a variety of data and on-site interviews with stake holders, and (2) whether change of the business model of the Indian pharmaceutical industry helped the industry to continue to develop through 2005 by avoiding negative impact from the introduction of product patents. It is believed that this study may be valuable when considering such developing countries as they plan to set up a patent system that would be suitable to the situation of each country.

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In this article, we discuss multi-production planning problem under the framework of cooperative game theory. Shapley value is employed to evaluate allocated risk, and the average value-at-risk (AVaR), a function managing risk mainly used to evaluate a loss distribution, is defined as characteristic function for singular player and respective coalitions. Opposite to the conventional Shapley value we treat the problem using quadratic programming models. Three models are proposed, namely Model 1.1 where production constraints are added directly to Shapley value [11]; Model 2 or Constrained Model using Shapley value and production constraints without considering individual rationality and Model 3, similar to the second, but with a weighting factor, w_{9, controled by decision-maker. Hence, the scheme proposed in this study seeks to satisfy, essentially, individual rationality and group rationality properties. The concept of penalty for each period is introduced, and by quantifying its value the decision-maker can forecast the production volume for those periods efficiently. A numerical illustration is also considered. Abstract In this article, we discuss multi-production planning problem under theory. Shapley value is employed to evaluate allocated risk, and the tion managing risk mainly used to evaluate a loss distribution, is defined singular player and respective coalitions. Opposite to the conventional using quadratic programming models. Three models are proposed, namely straints are added directly to Shapley value [11]; Model 2 or Constrained production constraints without considering individual rationality and with a weighting factor, w_{9, controled by decision-maker. Hence, the scsatisfy, essentially, individual rationality and group rationality properties. period is introduced, and by quantifying its value the decision-maker can those periods efficiently. A numerical illustration is also considered.

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In a retail store, some persons shop alone, while others shop in groups of two or three. Prior marketing research focused on the purchase behavior of one person, suggesting that only a part of the purchase behavior in a store has been studied. In this study, we focus on the purchase behavior of a group. The purchase behavior of a group of two or more persons is different from the purchase behavior of one person as the interpersonal relationship affects the purchase. Heider, a social psychologist, constructed a theory regarding a mechanism of interrelationship from a socio-psychological perspective. Heider simply described how an attitude of a person towards others becomes balanced in a three-party interpersonal relationship, and expanded the theory to include correlations among persons, objects, and concepts. With regards to using attitude to determine a consumer's purchase in this study, if his/her attitude towards a product is divided within the group, persuasion is used to influence purchase behavior. This proposed model plays a role in expanding the breadth of the marketing study. An application of multi-agent simulation to virtual collaboration of various fashion leaders can be considered.

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