Tadashi Imaizumi

Tadashi Imaizumi
Tama University · School of Management & Information Sciences

About

35
Publications
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298
Citations
Introduction
Multi-Dimensional Data Analysis Cluster Analysis Multi-Dimensional Scalinf

Publications

Publications (35)
Article
Full-text available
What is known and objective: In our previous studies, we developed a cross-resistance rate (CRR) correlation diagram (CRR diagram) that visually captures the magnitude of CRRs between antimicrobials using scatter plots. We used asymmetric multidimensional scaling (MDS) to transform cross-resistance similarities between antimicrobials into a 2-dime...
Chapter
As methods of analyzing the relationship of n objects of proximity matrix, multidimensional scaling (MDS) has been developed and applied to many data sets. However, we take care to apply them to an asymmetric proximity matrix. Okada and Imaizumi have been proposed so-called “circle (or radius–distance) model” by introducing the radius of each objec...
Book
This book focuses on the latest developments in behaviormetrics and data science, covering a wide range of topics in data analysis and related areas of data science, including analysis of complex data, analysis of qualitative data, methods for high-dimensional data, dimensionality reduction, visualization of such data, multivariate statistical meth...
Book
This edited volume focuses on the latest developments in classification and data science and covers a wide range of topics in the context of data analysis and related areas, e.g. the analysis of complex data, analysis of qualitative data, methods for high-dimensional data, dimensionality reduction, data visualization, multivariate statistical metho...
Chapter
Similarity matrix represents the relationship of n objects and gives us a useful information about these objects. Several models for analyzing this data assume that each object of n objects is embedded as a point or a vector in t dimensional “common space” of n objects in general. However, these models are not appropriate for analyzing a sparse blo...
Book
This volume presents theories, models, algorithms, and applications in clustering, classification, and visualization. It also includes applications of clustering, classification, and visualization in various fields such as marketing, recommendation system, biology, sociology, and social survey. The contributions give insight into new models and con...
Article
The university enrollment flow among Japanese 47 prefectures for 31 years from 1972 through 2002 was analyzed. University enrollment flow data in the present study consist of 31 tables. Each table is 47×47, the (j, k) element of the i-th table, corresponding to year i, is the number of high school graduates in prefecture j who entered into universi...
Conference Paper
The purpose of the present study is to introduce a model and the associated nonmetric algorithm of multidimensional scaling for analyzing one-mode two-way (object x object) asymmetric proximities. In the model each object is represented as a point in a multidimensional Euclidean space, and a point, called the dominance point, is also embedded in th...
Chapter
A new model for analyzing two-way, two-mode preference data is proposed. MultiDimensional Unfolding models (MDU) have been used widely. In these model, the observed preference value is related to the distance between the ideal point and object point only. The market share of each brand is ignored or assumed to be be the same for all objects. The at...
Chapter
The unfolding model has been widely used as a model for preferential choice data. This model is treated as the special case of multidimensional scaling with so-called “ideal” points. In this model, the distance between an “ideal” point and object points are related to the degree of individual preferential choice data for objects. However, the unfol...
Chapter
A joint space model and an associated nonmetric algorithm to analyze two-mode three-way asymmetric proximities (object × object × source) are presented. Each object is represented as a point and a circle (sphere, hyper sphere) in the common joint configuration which is common to all sources. Each source is represented as a point in the common joint...
Article
Relationships among managers of a firm were analyzed. Each manager responded who goes to whom for help or advice for work-related problems. Resulting responses constitute a set of matrices, each comes from a manager. Each matrix is transformed to a matrix of geodesic distances from row to column managers. The set of geodesic distance matrices was a...
Conference Paper
An external analysis of two-mode three-way (object×object×source) asymmetric multidimensional scaling is introduced, which is similar to the external analysis of INDSCAL. The present external analysis discloses the asymmetry of each object, and source differences in symmetric and in asymmetric proximity relationships among objects respectively for...
Article
A layout of a supermarket, which increases the jointly purchasing items of different categories, was developed based on purchase data of more than 14,000 customers for half a year at a supermarket. Similarities among 24 categories of items sold at the supermarket were defined, for each of 12 conditions (the age of the customers, the place they live...
Chapter
A model and an associated nonmetric algorithm of multidimensional scaling (MDS) for analyzing two-mode three-way (object×object×source) asymmetric proximities are introduced. The model and the algorithm of the present two-mode three-way asymmetric MDS were extended from those of Okada and Imaizumi (1997) which can represent differences of symmetric...
Chapter
A model and an associated nonmetric algorithm for multidimensional scaling of two-mode three-way asymmetric proximities or a set of proximity matrices, where each matrix can be asymmetric, is presented. The present model is extended from that of (1997), and can represent differences among sources both in symmetric and in asymmetric proximity relati...
Article
A model and an associated nonmetric algorithm for analyzing two-mode three-way asymmetric proximities are presented. The model represents proximity relationships among objects which are common to all sources, the salience of symmetric proximity relationships along dimensions for each source, and the salience of asymmetric proximity relationships al...
Conference Paper
A new fuzzy k-means clustering method is proposed by introducing crisp regions of clusters. Boundaries of the regions are determined by hyperbolas and membership values are given by one or zero in each region. The area between crisp regions is a fuzzy region, where membership values are proportional to distances to crisp regions. A new method is a...
Article
A new fuzzy k-means clustering algorithm is proposed by introducing crisp regions of clusters. Boundaries of the regions are determined by hyperbolas and membership values are given by one or zero in each region. The area between crisp regions is a fuzzy region, where membership values are proportional to distances to crisp regions. Though the trad...
Chapter
A model and an accompanying algorithm for two-mode three-way asymmetric multidimensional scaling is presented. The present model has a constraint on asymmetry, compared with the model of Okada, Imaizumi (1997) where each source has a different magnitude of asymmetry, but all sources are constrained so that the relative importance of the asymmetry a...
Conference Paper
A fuzzy correlation coefficient is proposed for fuzzy random variables from the practical viewpoint, by using correlation coefficients between points in their level sets. The proposed correlation coefficient is applied to the analysis of the relationship between the meaning of the word “tall” and individual heights
Article
This paper presents an extended model of the ADCLUS model as a model for overlapping clustering. It is assumed that the degree of the belonging of each object to a cluster is represented as a binary random variable, and similarity between two objects is defined by a weighted expectation of a cross product of these variables. The problems on the vis...
Article
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...
Article
A fuzzy hypothesis is introduced and a testing method of a fuzzy hypothesis is proposed for random data. The proposed test produces a conclusion which is also fuzzy. Some applications of the fuzzy statistical test are demonstrated. Particularly the test of the difference of two population means is considered in detail and the fuzzy hypothesis that...
Article
A statistical model based on fuzzy random variables is proposed for fuzzy data which includes randomness and fuzziness simultaneously. The effectiveness of the model is clarified. Using this model, we show that the statistical inference on fuzzy data can be reduced to an ordinary statistical problem containing only randomness according to circumsta...
Chapter
This chapter discusses a hierarchical clustering method for dissimilarity matrices with individual differences. The methods for hierarchical clustering help to visualize the result of clustering by a tree diagram. A tree diagram can be used to construct a new dissimilarity matrix between objects. The hierarchical clustering process can be described...
Article
Full-text available
This paper proposes a model to analyze the symmetric dissimilarity matrix by an Euclidean distance model with additional terms. The proposed model is a restricted model of Weeks and Bentler's model. The symmetric dissimilarity is assumed to be induced from asymmetric dissimilarities. A Monte Carlo simulation study conducted demonstrated that the pr...
Article
Nonmetric multidimensional scaling which could be applied to a square asymmetric interstimulus proximity matrix is presented. In the model each stimulus is represented as a point and a circle (sphere, hypersphere) whose center is at that point in a multidimensional Euclidean space . The radius of a circle (sphere, hypersphere) tells the skew-symmet...
Article
A new method is introduced which can explain individual differences in dissimilarity judgments by N subjects. The method is based on a weighted distance model which is a generalization of DeLeeuw and Pruzansky's model to Minkowski r metric. A set of N dissimilarity matrices is analyzed nonmetrically to derive a group stimulus configuration and a su...
Article
An introduction for preparing manuscripts for the conference volume of The 72nd Annual Meeting of the Psychometric Society held on 9-13 July, 2007 is pro- vided in this paper. This paper is written in a format to be used for all manuscripts and illustrates the final appearance for workshop papers. It is very important to follow these instructions t...

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