Tama University

About: Tama University is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Multidimensional scaling & Matrix (mathematics). The organization has 43 authors who have published 93 publications receiving 422 citations.

Asymmetric Multidimensional Scaling of Two-Mode Three-Way Proximities

Abstract: An asymmetric multidimensional scaling model and an associated nonmetric algorithm to analyze two-mode three-way proximities (object × object × source) are introduced. The model consists of a common object configuration and two kinds of weights, i.e., for both symmetry and asymmetry. In the common object configuration, each object is represented by a point and a circle (sphere, hypersphere) in a Euclidean space. The common object configuration represents pairwise proximity relationships between pairs of objects for the ‘group’ of all sources. Each source has its own symmetry weight and a set of asymmetry weights. Symmetry weights represent individual differences among sources of data in symmetric proximity relationships, and asymmetry weights represent individual differences among sources in asymmetric proximity relationships. The associated nonmetric algorithm, based on Kruskal’s (1964b) nonmetric multidimensional scaling algorithm, is an extension of the algorithm for the asymmetric multidimensional scaling of one mode two-way proximities developed earlier (Okada and Imaizumi 1987). As an illustrative example, we analyze intergenerational occupational mobility from 1955 to 1985 in Japan among eight occupational categories.

Analysis of impact of geographic characteristics on suicide rate and visualization of result with Geographic Information System.

Abstract: Aim The aim of our study was to understand the geographic characteristics of Japanese communities and the impact of these characteristics on suicide rates. Methods We calculated the standardized mortality ratio from suicide statistics of 3318 municipalities from 1972 to 2002. Correlation analysis, multi-regression analysis and generalized additive model were used to find the relation between topographic and climatic variables and suicide rate. We visualized the relation between geographic characteristics and suicide rate on the map of Wakayama Prefecture, using the Geographic Information System. Results Our study showed that the geographic characteristics of each community are related with its suicide rate. The strongest factor among the geographic characteristics to increase the suicide rate was the slope of the habitable land. Conclusions It is necessary to take the characteristics of each community into consideration when we work out measures of suicide prevention. Visualization of the findings on the local map should be helpful to promote understanding of problems and to share the information among various parties in charge of suicide prevention.

Orthographic representation and variation within the Japanese writing system Some corpus-based observations

Abstract: Given its multi-scriptal nature, the Japanese writing system can potentially yield some important insights into the complex relationships that can exist between units of language and units of writing. This paper discusses some of the difficult issues surrounding the notions of orthographic representation and variation within the Japanese writing system, as seen from the perspective of creating word lists based on the Kokuritsu Kokugo Kenkyūjo’s ‘Balanced Corpus of Contemporary Written Japanese’ (BCCWJ) Project. More specifically, the paper (i) reflects on the treatment of lemmas within UniDic, the morphological analyzer dictionary developed for the project, (ii) notes some concerns for extracting word lists that stem from the project’s approach towards defining orthographic words which draws on its conceptualization of short and long unit words, and (iii) attempts to quantify the extent of orthographic variation within the Japanese writing system as represented by the BCCWJ. Keywords: Japanese; Balanced Corpus of Contemporary Written Japanese (BCCWJ); kanji; hiragana; katakana; orthographic variation; UniDic