Updated on 2024/12/13

写真a

 
SAKAMOTO Wataru
 
Organization
Faculty of Environmental, Life, Natural Science and Technology Professor
Position
Professor
Homepage
https://sites.google.com/site/sakamotoemsokayama/
External link

Degree

  • Ph.D in Engineering ( 1998.3   Osaka University )

Research Interests

  • Statistical Science

Research Areas

  • Informatics / Statistical science  / 計算統計学，正則化法，ベイズ統計

Education

  • Osaka University   大学院基礎工学研究科   数理系専攻 博士後期課程

    1995.4 - 1998.3

    　 More details

    Country： Japan

    researchmap

  • Osaka University   大学院基礎工学研究科   数理系専攻 博士前期課程

    1993.4 - 1995.3

    　 More details

  • Kyoto University   理学部  

    1989.4 - 1993.3

    　 More details

    Notes： 主として数学を専攻

    researchmap

Research History

  • Okayama University   学術研究院環境生命自然科学学域（工学系）   Professor

    2023.4

    　 More details

    Country：Japan

    Notes：組織変更

    researchmap

  • Okayama University   学術研究院環境生命科学学域   Professor

    2021.4 - 2023.3

    　 More details

    Country：Japan

    Notes：組織変更（教教分離）

    researchmap

  • Okayama University   Division of Human Ecology, Graduate School of Environmental and Life Science   Professor

    2013.4 - 2021.3

    　 More details

    Country：Japan

    researchmap

  • Osaka University   Graduate School of Engineering Science Department of Systems Innovation Division of Mathematical Science   Associate Professor

    2007.4 - 2013.3

    　 More details

    Country：Japan

    Notes：職名変更

    researchmap

  • Osaka University   Graduate School of Engineering Science Department of Systems Innovation Division of Mathematical Science   Associate Professor (as old post name)

    2003.10 - 2007.3

    　 More details

  • Osaka University   Graduate School of Engineering Science   Research Assistant

    1998.4 - 2003.9

    　 More details

    Country：Japan

    researchmap

▼display all

Professional Memberships

▼display all

Committee Memberships

  • 日本統計学会   代議員  

    2021.4 - 2023.3   

    　 More details

    Committee type：Academic society

    researchmap

  • 情報・システム研究機構・統計数理研究所   統計思考院運営委員会  

    2017.2 - 2019.3   

    　 More details

    Committee type：Other

    researchmap

  • The Asian Regional Section of the International Association for Statistical Computing   Board of Directors member  

    2016.1 - 2019.12   

    　 More details

    Committee type：Academic society

    researchmap

  • International Association for Statistical Computing   Scientific Secretary  

    2009.8 - 2011.8   

    　 More details

    Committee type：Academic society

    researchmap

  • 日本計算機統計学会   評議員・理事  

    2001.1   

    　 More details

    Committee type：Academic society

    評議員 (2003-2016, 2018-2020)
    庶務理事 (2001-2006)
    企画理事 (2007-2010)
    渉外理事 (2013-2014)
    欧文誌編集理事 (2015-2018)
    国際交流理事 (2019-2020)

    researchmap

  • 日本計量生物学会   評議員  

    2013.1 - 2018.12   

    　 More details

    Committee type：Academic society

    researchmap

  • 日本統計学会   理事（広報）  

    2006.9 - 2008.8   

    　 More details

    Committee type：Academic society

    researchmap

  • 特定非営利活動法人 医学統計研究会   理事  

    2006.4 - 2021.3   

    　 More details

    Committee type：Other

    医学統計研究会

    researchmap

▼display all

 

Papers

  • Spatio-temporal clustering analysis using generalized lasso with an application to reveal the spread of Covid-19 cases in Japan Reviewed

    Septian Rahardiantoro, Wataru Sakamoto

    Computational Statistics   39   1513 - 1537   2023.4

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

    DOI： 10.1007/s00180-023-01331-x

    researchmap

    Other Link： https://link.springer.com/article/10.1007/s00180-023-01331-x/fulltext.html

  • Bias‐reduced marginal Akaike information criteria based on a Monte Carlo method for linear mixed‐effects models Reviewed International journal

    Wataru Sakamoto

    Scandinavian Journal of Statistics   46 ( 1 )   87 - 115   2019.3

    　More details

    Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

    DOI： 10.1111/sjos.12339

    researchmap

    Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1111/sjos.12339

  • Statistical Issues on Japanese Criteria of Metabolic Syndrome Reviewed

    SAKAMOTO Wataru, ISOGAWA Naoki, GOTO Masashi

    Kodo Keiryogaku   35 ( 2 )   177 - 192   2008

    　More details

    Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Behaviormetric Society of Japan  

    The article by The Examination Committee of Criteria for 'Obesity Disease' in Japan and Japan Society for the Study of Obesity (2002) established cut-off points of waist circumference at 85 cm for males and 90 cm for females as criteria of obesity disease. Their article has also become a basis for criteria of metabolic syndrome in Japan; however, their article has various problems on statistical aspects. How the criteria on waist circumference should vary was investigated through reexamination based on descriptions in their article. First, their article obtained criteria on visceral fat area (VFA) from data in which males and females were pooled, while our reexamination suggested that we should use separate criteria on VFA between males and females. Second, their article inappropriately used regression lines to estimate waist circumference corresponding to VFA cut-off points. Our reexamination with errors-in-variables models suggested alternative cut-off points of waist circumference at 87 cm for males and 85 cm for females. Our simulation confirmed that the criteria by their article might lead to inappropriate diagnosis which is strict for males and easy for females.

    DOI： 10.2333/jbhmk.35.177

    CiNii Article

    researchmap

  • 罰則付きスプラインによる非線形回帰構造の推測 Reviewed

    坂本 亘, 井筒理人, 白旗慎吾

    計算機統計学   21 ( 1-2 )   55 - 94   2008

    　More details

    Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • EXTRACTING NON-LINEAR ADDITIVE REGRESSION STRUCTURE WITH POWER-ADDITIVE SMOOTHING SPLINES Reviewed

    Sakamoto Wataru

    Journal of the Japanese Society of Computational Statistics   20 ( 1 )   83 - 108   2007

    　More details

    Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society of Computational Statistics  

    The additive regression model assumes additivity among explanatory variables and other rigid requirements, which might give poor estimation of regression functions. Transforming response variables is a useful method to diagnose additivity and other requirements. From a practical point of view, parametric transformations such as the Box-Cox power transformation would give more helpful suggestions in interpreting results of analysis than nonparametric transformations. The power additive smoothing spline (PASS) model is proposed to diagnose the validity of assuming additivity in the additive regression model. The smooth functions (and often regression parameters) are estimated with a penalized likelihood approach, and the power and the smoothing parameters, which govern global nonlinear regression structure, are estimated with the empirical Bayes method, in which a Laplace approximation of the marginal likelihood is developed. The PASS model is applied to some data sets, and also its performance is examined through a simulation experiment. It is shown that the PASS model can extract an appropriate regression structure if true structure is additive after a Box-Cox power transformation of responses.

    DOI： 10.5183/jjscs1988.20.83

    CiNii Article

    CiNii Books

    researchmap

  • MARS: selecting basis functions and knots with an empirical Bayes method Reviewed

    Wataru Sakamoto

    COMPUTATIONAL STATISTICS   22 ( 4 )   583 - 597   2007

    　More details

    Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER HEIDELBERG  

    An empirical Bayes method to select basis functions and knots in multivariate adaptive regression spline (MARS) is proposed, which takes both advantages of frequentist model selection approaches and Bayesian approaches. A penalized likelihood is maximized to estimate regression coefficients for selected basis functions, and an approximated marginal likelihood is maximized to select knots and variables involved in basis functions. Moreover, the Akaike Bayes information criterion (ABIC) is used to determine the number of basis functions. It is shown that the proposed method gives estimation of regression structure that is relatively parsimonious and more stable for some example data sets.

    DOI： 10.1007/s00180-007-0075-7

    Web of Science

    researchmap

  • Diagnosing Homoscedasticity with the Power-weighted Smoothing Spline Reviewed

    SAKAMOTO Wataru

    Ouyou toukeigaku   33 ( 1 )   27 - 49   2004

    　More details

    Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society of Applied Statistics  

    In nonparametric regression models, the requirements of homoscedasticity and so on are implicitly assumed, which leads to poor estimation of regression functions. A power weighted smoothing spline (PWSS) model, whose objective is to diagnose homoscedasticity as well as to estimate unknown nonlinear regression structure, is assumed. The responses in an additive regression model are power-transformed, and then their variances after transformation are assumed to be constant. Smoothing splines are obtained as estimated functions by maximizing the penalized likelihood, and a reweighted version of a backfitting algorithm is constructed. A power-transformation parameter and smoothing parameters, which control smoothness of the functions, are estimated by maximizing the marginal likelihood, based on Bayesian approaches to smoothing splines. A form of the marginal likelihood, which yields comparatively easy computation, is derived using the property that smoothing splines are the best linear unbiased predictor of a linear mixed model. Examination of some data sets from the literature and a simulation experiment show that the power transformation estimated with the PWSS model attains homoscedasticity while taking nonlinear structure into account.

    DOI： 10.5023/jappstat.33.27

    CiNii Article

    CiNii Books

    researchmap

    Other Link： https://jlc.jst.go.jp/DN/JALC/00242632045?from=CiNii

  • 制限付き最尤推定法による平滑化パラメータの選定：効率的な計算方式とその適用 Reviewed

    坂本 亘

    計算機統計学   15 ( 1 )   19 - 45   2002

    　More details

    Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • Likelihood-based cross-validation score for selecting the smoothing parameter in maximum penalized likelihood estimation Reviewed

    W Sakamoto, S Shirahata

    COMMUNICATIONS IN STATISTICS-THEORY AND METHODS   28 ( 7 )   1671 - 1698   1999

    　More details

    Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MARCEL DEKKER INC  

    Maximum penalized likelihood estimation is applied in non(semi)-parametric regression problems, and enables us exploratory identification and diagnostics of nonlinear regression relationships. The smoothing parameter lambda controls trade-off between the smoothness and the goodness-of-fit oof a function. The method of cross-validation is used for selecting lambda, but the generalized cross-validation, which is based on the squared error criterion, shows bad behavior in non-normal distribution and can not often select reasonable lambda. The purpose of this study is to propose a method which gives more suitable lambda and to evaluate the performance of it.
    A method of simple calculation for the delete-one estimates in the likelihood-based cross-validation (LCV) score is described. A score of similar form to the Akaike information criterion (AIC) is also derived. The proposed scores are compared with the ones of standard procedures by using data sets in literatures. Simulations are performed to compare the patterns of selecting lambda and overall goodness-of-fit and to evaluate the effects of some factors.
    The LCV scares by the simple calculation provide good approximations to the exact one if lambda is not extremely small. Furthermore the LCV scores by the simple calculation have little risk of choosing extremely small lambda and make it possible to select lambda adaptively. They have the effect of reducing the bias of estimates and provide better performance in the sense of overall goodness of-fit. These scores are useful especially in the case of small sample size and in the case of binary logistic regression.

    Web of Science

    researchmap

  • SIMPLE CALCULATION OF LIKELIHOOD-BASED CROSS-VALIDATION SCORE IN MAXIMUM PENALIZED LIKELIHOOD ESTIMATION OF REGRESSION FUNCTIONS Reviewed

    Sakamoto Wataru, Shirahata Shingo

    Journal of the Japanese Society of Computational Statistics   10 ( 1 )   27 - 40   1997

    　More details

    Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society of Computational Statistics  

    In maximum penalized likelihood estimation, approaches of cross-validation (CV) are often useful in selecting a smoothing parameter. The CV score based on squared-error criterion behaves more badly than the likelihood-based score. However, it is expensive to calculate the likelihood-based score. Hence we propose a method for simple calculation of this score. The simple calculation is derived as an analogue of the deletion lemma in ordinary or penalized least squares, and is shown to be related to the one-step approximation to the estimates of parameters for the Newton-Raphson method. Our method is applied to binary data from some case studies in the context of logistic regression. It is illustrated that the simple calculation method well behaves and gives a good approximation to the likelihood-based score calculated by the delete-one method,

    DOI： 10.5183/jjscs1988.10.27

    CiNii Article

    CiNii Books

    researchmap

  • セミパラメトリック回帰問題におけるスプライン平滑化 Reviewed

    坂本 亘, 白旗慎吾

    計算機統計学   9 ( 1 )   13 - 35   1996

    　More details

    Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)  

    CiNii Article

    researchmap

  • Optimum Tuning Parameter Selection in Generalized lasso for Clustering with Spatially Varying Coefficient Models Reviewed

    Septian Rahardiantoro, Wataru Sakamoto

    IOP Conference Series: Earth and Environmental Science   950 ( 1 )   012093 - 012093   2022.1

    　More details

    Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

    Abstract

    Spatial clustering with spatially varying coefficient models is useful for determining the region with common effects of variables in spatial data. This study focuses on selecting the optimum tuning parameter of the generalized lasso for clustering with the spatially varying coefficient model. The k-fold cross-validation (CV) may fail to split spatial data into a training set and a testing set, if a region contains only a few observations. Moreover, the k-fold CV is known to give a biased estimate of the out-of-sample prediction error. Therefore, we investigated the performance of approximate leave-one-out cross-validation (ALOCV) in comparison with k-fold CV for selecting the tuning parameter in a simulation study on 2-dimensional grid. The ALOCV yielded smaller error than k-fold CV and could detect edges with differences shrunk by generalized lasso appropriately. Then, the ALOCV for selecting the optimum tuning parameter of the generalized lasso in fitting the spatially varying coefficient model is applied to the Chicago crime data. The result of selection by ALOCV was in accordance with the conclusion suggested in the preceding literature. Clustering into regions in advance for making k-fold CV feasible may lead to a wrong result of clustering with a spatially varying coefficient model.

    DOI： 10.1088/1755-1315/950/1/012093

    researchmap

    Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/950/1/012093/pdf

  • Multiple mutations in RNA polymerase β-subunit gene (rpoB) in Streptomyces incarnatus NRRL8089 enhance production of antiviral antibiotic sinefungin: modeling rif cluster region by density functional theory Reviewed International journal

    Saori Ogawa, Hitomi Shimidzu, Koji Fukuda, Naoki Tsunekawa, Toshiyuki Hirano, Fumitoshi Sato, Kei Yura, Tomohisa Hasunuma, Kozo Ochi, Michio Yamamoto, Wataru Sakamoto, Kentaro Hashimoto, Hiroyuki Ogata, Tadayoshi Kanao, Michiko Nemoto, Kenji Inagaki, Takashi Tamura

    Bioscience, Biotechnology, and Biochemistry   85 ( 5 )   1275 - 1282   2021.4

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

    <title>ABSTRACT</title>
    Streptomyces incarnatus NRRL8089 produces the antiviral, antifungal, antiprotozoal nucleoside antibiotic sinefungin. To enhance sinefungin production, multiple mutations were introduced to the rpoB gene encoding RNA polymerase (RNAP) β-subunit at the target residues, D447, S453, H457, and R460. Sparse regression analysis using elastic-net lasso-ridge penalties on previously reported H457X mutations identified a numeric parameter set, which suggested that H457R/Y/F may cause production enhancement. H457R/R460C mutation successfully enhanced the sinefungin production by 3-fold, while other groups of mutations, such as D447G/R460C or D447G/H457Y, made moderate or even negative effects. To identify why the rif cluster residues have diverse effects on sinefungin production, an RNAP/DNA/mRNA complex model was constructed by homology modeling and molecular dynamics simulation. The 4 residues were located near the mRNA strand. Density functional theory–based calculation suggested that D447, H457, and R460 are in direct contact with ribonucleotide, and partially positive charges are induced by negatively charged chain of mRNA.

    DOI： 10.1093/bbb/zbab011

    PubMed

    researchmap

    Other Link： http://academic.oup.com/bbb/article-pdf/85/5/1275/37329090/zbab011.pdf

  • Clustering Regions Based on Socio-Economic Factors Which Affected the Number of COVID-19 Cases in Java Island Reviewed

    Septian Rahardiantoro, Wataru Sakamoto

    Journal of Physics: Conference Series   1863 ( 1 )   012014 - 012014   2021.3

    　More details

    Authorship：Last author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

    DOI： 10.1088/1742-6596/1863/1/012014

    researchmap

    Other Link： https://iopscience.iop.org/article/10.1088/1742-6596/1863/1/012014/pdf

  • Microsimulation model for evaluating the effect of cancer control program: example for colorectal cancer Reviewed

    加茂憲一, 福井敬祐, 福井敬祐, 坂本亘, 伊藤ゆり

    計量生物学   41 ( 2 )   93 - 115   2021

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    J-GLOBAL

    researchmap

  • Meta-analysis of a continuous outcome combining individual patient data and aggregate data: a method based on simulated individual patient data Reviewed

    Yusuke Yamaguchi, Wataru Sakamoto, Masashi Goto, Jan A. Staessen, Jiguang Wang, Francois Gueyffier, Richard D. Riley

    Research Synthesis Methods   5 ( 4 )   322 - 351   2014.12

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

    DOI： 10.1002/jrsm.1119

    Web of Science

    researchmap

  • REGRESSION ANALYSIS USING LASSO RANDOM FOREST Reviewed

    Nakamura Masatoshi, Shimokawa Toshio, sakamoto Wataru, Goto Masashi

    Bulletin of the Computational Statistics of Japan   26 ( 1 )   17 - 31   2013

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society of Computational Statistics  

    Random Forest (RF) is one of tree-structured approaches, such as classification and regression trees, involved in ensemble learning method to predict outcome more precisely. In this paper we proposed an adjusted RF based on lasso (lasso-RF) for further predictive performance in regression analysis. In particular, we integrated lasso which use one of shrinkage estimators into the tree-structured model of RF. Practically we carried out two case studies and a small scale simulation with factors which influence prediction of outcome such as sample size {100, 200, 400}, methods {RF, lasso-RF} and bootstrap re-sampling times {100, 200, 400}, and evaluated predictive performance. Our case studies suggested that lasso-RF decreased the mean squared errors between true and estimate outcomes less than original RF. By our simulation study, we evaluated influencing factors on the mean squared errors based on analysis of variance with above three factors and their interaction, and showed that the factor of methods as fixed effect was significant at level 0.05 with proportion of variation 29.2%.

    DOI： 10.20551/jscswabun.26.1_17

    CiNii Article

    CiNii Books

    researchmap

  • An evaluation of treatment-covariate interaction in meta-analysis with marginalizing the missing individual patient data Reviewed

    Yamaguchi Y, Sakamoto W, Shirahata S, Goto M

    26 ( 1 )   1 - 16   2013

    　More details

    Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.5183/jjscs.1212001_203

    researchmap

  • PERFORMANCE EVALUATION OF BAYESIAN MODEL DIAGNOSTIC METHODS THAT FOCUS ON PREDICTION Reviewed

    Isogawa Naoki, Sakamoto Wataru, Goto Masashi

    Bulletin of the Computational Statistics of Japan   25 ( 1 )   1 - 13   2012

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society of Computational Statistics  

    In the framework of Bayesian approach, though we can select various prior distributions according to the situations, many models which should be evaluated exist. However, we think that the diagnosis methods for these models have proper diagnostic situations. In this paper, we consider two diagnostic methods that focus on prediction: the Bayesian predictive information criterion (BPIC) and the prior and posterior predictive checking approach (PCA) and conduct some simulations for the purpose of clarifying the feature of these methods and suggesting the effective diagnostic situations. As the results, regardless of whether the prior mean was true or not, BPIC showed the low values on the occasion with strong prior information, but PCA showed the high predictive checking probabilities on the occasion with weak prior information. So, it might happen that the model with non-true prior mean was selected by simulation setting. To select a proper model, it is necessary to find the performance of the model diagnoses in the situation before model evaluations.

    DOI： 10.20551/jscswabun.25.1_1

    CiNii Article

    CiNii Books

    researchmap

  • 「保健指導」に関する評価の試み Reviewed

    五十川直樹, 池邉淑子, 坂本 亘, 後藤昌司

    行動計量学   38 ( 1 )   51 - 63   2011

    　More details

    Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • Relationship between Transmission Intensity and Incidence of Dengue Hemorrhagic Fever in Thailand Reviewed

    Suwich Thammapalo, Yoshiro Nagao, Wataru Sakamoto, Seeviga Saengtharatip, Masaaki Tsujitani, Yasuhide Nakamura, Paul G. Coleman, Clive Davies

    PLoS Neglected Tropical Diseases   2 ( 7 )   e263 - e263   2008.7

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Public Library of Science (PLoS)  

    DOI： 10.1371/journal.pntd.0000263

    researchmap

  • 関数データの判別分析―線形的手法と関数部分空間法 Reviewed

    Dou Xiaoling, 白旗慎吾, 坂本 亘

    計算機統計学   19 ( 1 )   13 - 30   2006

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • AICによるウェーブレット基底関数の選択 Reviewed

    松嶋優貴, 白旗慎吾, 坂本 亘

    応用統計学   33 ( 2 )   201 - 219   2004

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • Statistical evaluation of umbrella dose-response relationships Reviewed

    Baba M, Fujisawa M, Sakamoto W, Goto M

    Journal of the Japanese Society of Computational Statistics   15 ( 2 )   281 - 294   2003

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society of Computational Statistics  

    In the drug development process, it is essential to assess the relationship (mechanism) between dose and response of a biological system following drug administration. This mechanism is known as the "dose-response relationship". Then, dose-response relationships are often evaluated based on a monotonic hypothesis. However, in practice, we may often encounter non-monotonic dose-response relationships, such as the umbrella relationship, which then makes interpretation of the relationships somewhat problematic. In this paper, to assess such umbrella dose-response relationships, the cumulative dose logit model is proposed and applied to an example. To evaluate properties of this model, some Monte-Carlo studies are performed. The results of the cumulative dose logit model are compared with those of the quadratic logit model. This indicates that the cumulative dose logit model provides more stable estimates than the quadratic logit model in estimating the maximum effective dose. It is suggested that the cumulative dose logit model is appropriate for assessing non-monotonic dose-response relationships.

    CiNii Article

    CiNii Books

    researchmap

  • CONSTRUCTION OF CONFIDENCE BANDS FOR SIMPLE LINEAR REGRESSION OVER BOUNDED INTERVALS Reviewed

    Fujisawa Masaki, Baba Mitsumasa, Sakamoto Wataru, Goto Masashi

    Bulletin of the Computational Statistics of Japan   14 ( 1 )   29 - 44   2002

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society of Computational Statistics  

    In this article, we discuss methods to construct confidence bands for regression function, especially to construct uniform width-confidence bands and trapezoidal confidence bands in a finite interval of interest. With case studies and numerical experiments, we examined the coverage probability and the efficiency (area ratio) of these confidence bands. From a viewpoint of the coverage probability, it is reasonable to use the uniform width- confidence bands (Gafarian bands) and trapezoidal confidence bands (Bowden-Graybill bands) for the finite interval of interest, rather than to use the Working-Hotelling bands. In particular, the use of these confidence bands can be emphasized when a length of the interval of interest is smaller than that of the observation interval. Moreover, from the examination about efficiency, it is strongly recommended to use the trapezoidal confidence bands when the interval of interest is near the relative ends of the observation interval.

    DOI： 10.20551/jscswabun.14.1_29

    CiNii Article

    CiNii Books

    researchmap

  • Likelihood Ratio Test in the Two Phase Linear Regression Problem. Reviewed

    BIAN Qi, SAKAMOTO Wataru, SHIRAHATA Shingo

    Ouyou toukeigaku   26 ( 3 )   135 - 150   1997

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society of Applied Statistics  

    DOI： 10.5023/jappstat.26.135

    CiNii Article

    researchmap

▼display all

Books

  • 統計学辞典

    白旗慎吾, 内田雅之, 熊谷悦生, 黒木 学, 阪本雄二, 坂本 亘

    共立出版  2010.10  （ ISBN:9784320019393 ）

    　More details

    Total pages：vi, 512p   Language：Japanese

    CiNii Books

    researchmap

MISC

  • Inference on variance components near boundary in linear mixed effect models Reviewed

    Wataru Sakamoto

    Wiley Interdisciplinary Reviews: Computational Statistics   11 ( 6 )   2019.11

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：Wiley  

    DOI： 10.1002/wics.1466

    researchmap

    Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/wics.1466

  • p 値と仮説検定：どう教えればよいか

    坂本 亘

    2017年度統計関連学会連合大会 講演報告集   2017.9

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • Cluster detection of disease mapping data based on latent Gaussian Markov random field models Reviewed

    Sakamoto, W

    Proceedings of COMPSTAT 2016: 22th International Conference on Computational Statistics (Oviedo, Spain)   267 - 277   2016.8

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • 医学統計概論―多変量解析とは―

    坂本 亘, 後藤昌司

    日本心血管インターベンション治療学会誌   2 ( 4 )   295 - 302   2010

    　More details

    Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

    researchmap

  • MARS: selecting basis and knots with the empirical Bayes method Reviewed

    Sakamoto, W

    Compstat 2006: Proceedings in Computational Statistics (CD-ROM) (Rome, Italy)   1397 - 1404   2006.8

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • 時間依存回帰係数をもつ罰則付き Cox モデルによる比例ハザード性の点検

    西田尚樹, 坂本 亘

    日本計算機統計学会第38回シンポジウム講演論文集   194 - 197   2024.10

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • 一般化極値分布上の分位点回帰におけるSSVS法による変数選択

    近藤野十夏, 坂本亘

    日本計算機統計学会第38回シンポジウム講演論文集   232 - 235   2024.10

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • 構造的因果モデルに基づく因果効果識別方法の検討

    塩飽大基, 坂本亘, 山本倫生

    日本行動計量学会第50回大会抄録集   2022.8

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • 計算機統計学に関連する国内外の学会・雑誌の動向

    坂本 亘

    エストレーラ   ( 328 )   2021.7

    　More details

    Authorship：Lead author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (bulletin of university, research institution)  

    researchmap

  • 数理モデルによる大腸腫瘍発生過程のシミュレーション

    坂本 亘, 伊森晋平, 加茂憲一

    厚労科研総括・分担報告書   22 - 25   2017.3

    　More details

    Language：Japanese  

    researchmap

  • 代替変数によるインフルエンザ流行予測の改良

    澤井啓介, 坂本亘

    日本計算機統計学会第30回シンポジウム講演論文集   69 - 72   2016.11

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • ラザニアプロットを用いた経時データの視覚化

    兼田麻里奈, 坂本亘

    日本計算機統計学会第30回シンポジウム講演論文集   177 - 178   2016.11

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • 過分散を考慮した癌罹患データの空間解析

    宮下司, 坂本亘

    日本計算機統計学会第30回シンポジウム講演論文集   73 - 76   2016.11

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • An analysis of Japanese liver cancer mortality data with Bayesian age-period-cohort models

    Proceedings of the International Conference for JSCS 30th Anniversary in Seattle   2016.10

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • 数理モデルによる腫瘍発生過程のシミュレーション

    坂本 亘, 伊森晋平, 加茂憲一

    厚労科研総括・分担研究報告書   26 - 30   2016.3

    　More details

    Language：Japanese  

    researchmap

  • がん対策推進基本計画の効果検証と目標設定に関する研究 肝臓がん自然史モデルに対する数理モデルと推定アルゴリズムについて

    伊森晋平, 田中純子, 加茂憲一, 坂本亘, 伊藤ゆり, 福井敬祐

    がん対策推進基本計画の効果検証と目標設定に関する研究 平成27年度 総括・分担研究報告書   2016

    　More details

  • 数理モデルによる腫瘍発生のマイクロシミュレーション

    坂本 亘, 伊藤ゆり, 加茂憲一

    厚労科研総括・分担研究報告書   32 - 35   2015.3

    　More details

    Language：Japanese  

    researchmap

  • メタ・アナリシスの要点と解釈 Invited

    山口祐介, 坂本亘, 後藤昌司

    骨粗鬆症治療   14 ( 3 )   264 - 267   2015

    　More details

    Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：先端医学社  

    CiNii Article

    CiNii Books

    researchmap

    Other Link： http://search.jamas.or.jp/link/ui/2016087928

  • 一般化線形混合モデルに対するINLAによるBayes流推測の性能評価

    萩原 駿祐, 坂本 亘

    日本計算機統計学会第27回シンポジウム論文集   27   131 - 134   2013.11

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)   Publisher：日本計算機統計学会  

    DOI： 10.20551/jscssymo.27.0_131

    CiNii Article

    CiNii Books

    researchmap

  • A meta-analysis method based on simulated individual patient data Reviewed

    Yamaguchi Y, Sakamoto W, Shirahata S, Goto M

    The 58th World Statistical Congress of the International Statistical Institute (ISI 2011): Proceedings (USB media, 6 pages). (Dublin, Ireland)   2011.8

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • Failure prediction method for network management system by using Bayesian network and shared database Reviewed

    Erwin Harahap, Wataru Sakamoto, Hiroaki Nishi

    8th Asia-Pacific Symposium on Information and Telecommunication Technologies, APSITT 2010   2010.6

    　More details

    Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    Network Management System (NMS) is a service that employs a variety of tools, applications, and devices to assist network administrators on monitoring and maintaining network. Keeping the network in high quality of service is the main purpose of NMS. This paper proposed a method to solve the network problem by making a prediction of failure based on network-data behavior. The prediction represented by conditional probability generated by Bayesian network. Bayesian network is a probability graphical model for representing the probabilistic relationship among a large number of variables and doing probabilistic inference with those variables. In order to describe how the prediction works, we discuss the prediction result by simulation on network congestion.

    Scopus

    researchmap

  • データ復元・拡大問題における計算統計の展望

    坂本 亘

    日本計算機統計学会・第24回シンポジウム講演論文集   105 - 108   2010

    　More details

    Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • Selecting an appropriate transformation of responses for fitting a linear or additive mixed model Reviewed

    Sakamoto, W

    Proceedings of the 57th Session of the International Statistical Institute (ISI 2009) (2 pages). Durban, South Africa)   2009.8

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • Selecting an appropriate transformation of responses for fitting a semiparametric mixed model Reviewed

    Sakamoto, W

    IASC2008: Joint Meeting of 4th World Conference of the IASC and 6th Conference of the Asian Regional Section of the IASC on Computational Statistics & Data Analysis: Proceedings (CD-ROM: 6 pages). (Yokohama, Japan)   2008.12

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • A simulation study on evaluating contribution of variables with empirical Bayes MARS Reviewed

    Sakamoto, W

    Bulletin of the International Statistical Institute 56th Session: Proceedings (CD-ROM: 4 pages). (Lisbon, Portugal)   2007.8

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • 経験Bayes法による多変量適応的回帰スプラインの基底および節点の選定

    坂本 亘

    日本計算機統計学会第20回大会講演論文集   20   165 - 168   2006

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)   Publisher：日本計算機統計学会  

    DOI： 10.20551/jscstaikai.20.0_165

    CiNii Article

    CiNii Books

    researchmap

  • MARS: selecting basis and knots with the empirical Bayes method Reviewed

    Sakamoto, W

    Proceedings of the 5th IASC Asian Conference on Statistical Computing (Hong Kong)   135 - 138   2005.12

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • Diagnosing non-linear regression structure with power additive smoothing splines

    Sakamoto, W

    Proceedings of the ISM/KIER Joint Conference on Nonparametric and Semiparametric Statistics (Tokyo, Japan)   249 - 262   2005.3

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • 近似最大周辺尤度法：平滑化スプライン・モデルへの応用

    坂本 亘

    「ノンパラメトリック・セミパラメトリック法を用いた統計解析理論とその学際的応用」研究報告書   217 - 229   2004

    　More details

    Publishing type：Meeting report  

    researchmap

  • Exploring nonlinear structure with nonparametric regression Reviewed

    Sakamoto, W

    Proceedings of the 54th Conference of the International Statistical Institute (CD-ROM) (Berlin, Germany)   2003.8

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • 制限付き最尤推定法による平滑化パラメータの選定：シミュレーションによる評価

    坂本 亘

    日本計算機統計学会第16回シンポジウム講演論文集   16   101 - 104   2002

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)   Publisher：日本計算機統計学会  

    DOI： 10.20551/jscssymo.16.0_101

    CiNii Article

    CiNii Books

    researchmap

  • Statistical evaluation of umbrella dose-response relationships Reviewed

    Baba M, Sakamoto W, Goto M

    Proceedings of the 4th ARS Conference of the IASC (Busan, Korea)   185 - 186   2002

    　More details

    Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • Approximation of maximum marginal likelihood in non-Gaussian nonparametric regression models Reviewed

    Sakamoto, W

    Proceedings of the 4th ARS Conference of the IASC (Busan, Korea)   22 - 25   2002

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • 制限付き最尤推定法による平滑化パラメータの選定

    坂本 亘

    統計数理研究所・共同研究リポート, No. 143, pp. 51-68.   143   51 - 68   2001

    　More details

    Publishing type：Article, review, commentary, editorial, etc. (bulletin of university, research institution)  

    researchmap

  • 平滑化スプラインによる非線形構造の探索

    坂本 亘

    統計数理研究所・共同研究リポート   134   27 - 42   2000

    　More details

    Publishing type：Article, review, commentary, editorial, etc. (bulletin of university, research institution)  

    researchmap

  • 制約付き最尤推定法による平滑化パラメータの選定

    坂本 亘

    第68回日本統計学会講演報告集   217 - 218   2000

    　More details

    Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • 平滑化パラメータの選定における制約付き最尤推定法の適用とその評価

    坂本 亘

    第67回日本統計学会講演報告集   404 - 405   1999

    　More details

    Publishing type：Research paper, summary (national, other academic conference)  

    researchmap

  • 平滑化パラメータの選定における制約付き最尤推定法の適用とその評価

    坂本 亘

    統計数理研究所・共同研究リポート   118   109 - 118   1999

    　More details

    Publishing type：Article, review, commentary, editorial, etc. (bulletin of university, research institution)  

    researchmap

  • ノンパラメトリック回帰における平滑化パラメータの制約付き最尤推定

    坂本 亘

    日本計算機統計学会第12回シンポジウム講演論文集   12   49 - 52   1998

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)   Publisher：日本計算機統計学会  

    DOI： 10.20551/jscssymo.12.0_49

    CiNii Article

    CiNii Books

    researchmap

  • Simple calculation of likelihood-based cross-validation score in maximum penalized likelihood estimation Reviewed

    Sakamoto W, Shirahata S

    Multivariate Analysis and Computing: Proceedings of the Ninth Korea and Japan Joint Conference of Statistics (KJCS-97), (Jeju-do, Korea)   267 - 272   1997.12

    　More details

    Language：English   Publishing type：Article, review, commentary, editorial, etc. (international conference proceedings)  

    researchmap

  • 罰則付き最尤推定における尤度に基づく交差確認得点の簡便計算

    坂本 亘, 白旗慎吾

    日本計算機統計学会第10回シンポジウム講演論文集   10   20 - 23   1996

    　More details

    Language：Japanese   Publishing type：Research paper, summary (national, other academic conference)   Publisher：日本計算機統計学会  

    DOI： 10.20551/jscssymo.10.0_20

    CiNii Article

    CiNii Books

    researchmap

▼display all

Presentations

  • Analysis of disease mapping data: how to detect clusters of higher prevalence more flexibly Invited

    Sakamoto, W

    ICMSDS 2020 (Bogor, Indonesia: Online)  2020.11.11 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    researchmap

  • Analysis of Spatial Data with a Gaussian Mixture Markov Random Field Model

    Sakamoto, W

    IASC-ARS/NZSA 2017  2017.12 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • Cluster detection of disease mapping data based on latent Gaussian Markov random field models Invited

    Wataru Sakamoto

    2016 IASC-ARS Conference (Daejeon, Korea)  2016.11 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    researchmap

  • Spatially varying coefficient modeling of numerical and categorical predictor variables in the generalized lasso

    Septian Rahardiantoro, Wataru Sakamoto

    IASC-ARS2022  2022.2.23 

    　More details

    Event date： 2022.2.21 - 2022.2.24

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • 馬蹄事前分布を用いたスパース回帰モデルの選択

    坂本 亘

    第６回かごしまデータ科学シンポジウム  2024.8.5 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    researchmap

  • Clustering Regions Based on Socio Economic Factors Which Affected the Number of COVID 19 Cases in Java Island

    S. Rahardiantoro, W. Sakamoto

    ICMSDS 2020  2020.11.11 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • Bayes 階層モデリングによる疾病地図解析

    坂本 亘

    大分統計談話会第60回大会  2019.10 

    　More details

    Presentation type：Oral presentation (general)  

    researchmap

  • 時空間従属構造を考慮した高リスク集積領域の同定

    坂本 亘

    大分統計談話会第58回大会  2018.10 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    researchmap

  • R Shiny implementation of lasagna plot: interactive manipulation and visualization of longitudinal data

    Sakamoto W, Kaneda M

    IFCS 2017  2017.8 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • ベイズ統計：結果から原因を推測する

    坂本 亘

    岡山大学公開講座2017「身近に広がる数学ＩＩ」  2017.7.30 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • Environmental and medical applications of latent Gaussian Markov random field models Invited

    Sakamoto, W.

    Utah State University Math and Stat Special Research Colloquium  2016.10 

    　More details

    Language：English   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • 統計的推測の基本

    坂本 亘

    医学統計研究会・定例シンポジウム2016 「医療で必要とされる統計的基礎知識」  2016.10 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • R による計量データの解析：パッケージと開発環境

    坂本 亘

    医学統計研究会特定主題セミナー｢臨床評価における計算環境Rとその課題｣  2015.11 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • Performance of Bayes inference with integrated nested Laplace approximation in generalized linear mixed effect models

    Hagihara, S, Sakamoto, W

    The 24th South Taiwan Statistics Conference and 2015 Chinese Institute of Probability and Statistics Annual Meeting (STSC/CIPS2015)  2015.6 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • Information criteria for linear mixed effect models: bias correction based on a Monte Carlo method

    2014.5 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • 潜在構造を伴う統計モデルの推測と その複雑さの制御 Invited

    坂本 亘

    広島大学統計科学研究拠点セミナー  2014 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • 医学統計の実践で起こる過誤～科学論文に見られる誤用から学ぶ～

    坂本 亘

    医学統計研究会・定例シンポジウム2012 「医療に必要とされる統計的基礎知識」  2012.10 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • Selecting an optimal mixed effect model based on information criteria Invited

    ISBIS 2012 (Bangkok, Thailand)  2012.6 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    researchmap

  • Selecting variance structure in mixed effect models by information criteria based on Monte Carlo approximations

    Sakamoto, W

    Joint Meeting of the 2011 Taipei International Statistical Symposium and 7th Conference of the Asian Regional Section of the IASC  2011.12 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • Selecting an optimal mixed effect model based on information criteria

    Sakamoto, W

    COMPSTAT'2010 (Paris, France)  2010.8 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • Rによる統計的シミュレーション入門

    医学統計研究会特定主題シンポジウム「臨床評価における計算環境Rとその周辺：S-Plusによる妥当性確認」  2010.6 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • シミュレーションの前と後：統計的観点

    五十川直樹, 坂本 亘, 後藤昌司

    医学統計研究会特定主題セミナー｢臨床評価過程におけるシミュレーションとその実際｣  2010.3 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • Bayes 流接近法の基礎

    坂本 亘

    医学統計研究会特定主題シンポジウム「臨床評価におけるBayes 流接近法」  2009.11 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • 生存時間解析に必要な統計的基礎知識

    坂本 亘

    医学統計研究会特定主題シンポジウム「患者像に基づく臨床評価の過程：癌患者の治療を中心に」  2009.9 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • Bayes 流接近法の基礎

    坂本 亘

    医学統計研究会特定主題シンポジウム「臨床評価におけるBayes 流接近法」  2009.3 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • Selecting an appropriate transformation of responses for fitting a semiparametric mixed model Invited

    Sakamoto, W

    International Joint Session of CSA, JSS and KSS. (Taipei)  2008.12 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    researchmap

  • 「メタボリック・シンドローム」診断基準の統計的問題

    坂本 亘

    第92回行動計量学会シンポジウム  2008.6 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • 「メタボリック･シンドローム」の統計的論拠について

    坂本 亘

    大分統計談話会・第37回大会  2008.2 

    　More details

    Presentation type：Oral presentation (general)  

    researchmap

  • Rによる統計的シミュレーション入門

    坂本 亘

    BRA特定主題セミナー「臨床評価における計算環境Rとその周辺：S-Plusによる妥当性確認」  2007.12 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • 「医学統計学」とその周辺：誤用と対策

    坂本 亘

    医学統計研究会定例シンポジウム「医療で必要とされる統計的基礎知識2007」  2007.10 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • 生存時間解析に必要な統計的基礎知識

    坂本 亘

    医学統計研究会特定主題セミナー「癌治療の評価における生存時間解析の方法  2007.9 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • Rによる統計的シミュレーション入門

    坂本 亘

    医学統計研究会特定主題シンポジウム「臨床評価における計算環境Rとその周辺：S-Plusによる妥当性確認」  2007.3 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • 「医学統計学」とその周辺：誤用と対策

    坂本 亘

    医学統計研究会定例シンポジウム「医療で必要とされる統計的基礎知識2006」  2006.11 

    　More details

    Presentation type：Public lecture, seminar, tutorial, course, or other speech  

    researchmap

  • 経験Bayes法による多変量適応的回帰スプラインの推定

    坂本 亘

    大分統計談話会・第34回大会  2006.10 

    　More details

  • Selecting basis and knots in MARS with an empirical Bayes method

    Sakamoto, W

    Conference on Nonparametric Statistics and Related Topics (Carleton University, Ottawa, Canada)  2006.9 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • Bayes 流樹木構造接近法の有用性

    大分統計談話会・第32回大会  2005.10 

    　More details

    Presentation type：Oral presentation (general)  

    researchmap

  • Diagnosing non-linear regression structure with power additive smoothing splines

    Sakamoto, W

    14th International Workshop on Matrices and Statistics (Auckland, NZ)  2005.3 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • 非正規型ノンパラメトリック回帰問題における平滑化パラメータの選定 ： 近似最大周辺尤度法

    坂本 亘

    大分統計談話会・第26回大会  2002.10 

    　More details

    Presentation type：Oral presentation (general)  

    researchmap

  • ノンパラメトリック回帰の諸法

    坂本 亘

    大分統計談話会・第20回会合  1999.9.30 

    　More details

    Presentation type：Oral presentation (invited, special)  

    researchmap

▼display all

Awards

  • IASC Young Researchers Award

    2006.9   COMPSTAT2006 (Rome, Italy)  

    　More details

Research Projects

  • Effective inference and selection of statistical models to represent latent structure in spatial data

    Grant number：26330042  2014.04 - 2017.03

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)  Grant-in-Aid for Scientific Research (C)

    Sakamoto Wataru

    　 More details

    Grant amount：\4160000 （ Direct expense: \3200000 、 Indirect expense：\960000 ）

    Some methods of making effective inference and selection in statistical models with high-dimensional latent variables are considered to reveal complicated latent structure in spacial and geographical data. It was shown that the method of detecting regions using estimated spatial effect, proposed for application to disease mapping data, had higher possibility of detecting regions with high risk than existing methods. Also it was suggested that the model selection method considered in the analysis of cancer mortality data with age-period-cohort (APC) models could estimate each effect appropriately, and give a new knowledge for interpretation.

    researchmap

  • Selecting an optimal mixed effect model based on simulation : theory and applications

    Grant number：21500275  2009 - 2011

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)  Grant-in-Aid for Scientific Research (C)

    SAKAMOTO Wataru

    　 More details

    Grant amount：\3250000 （ Direct expense: \2500000 、 Indirect expense：\750000 ）

    Mixed effect models are useful for analysis of data which are measured repeatedly for each individual, and have been applied to various fields such as medical and biological sciences. However, how to select an optimal mixed effect model has not been fully examined. We proposed a criterion to select such an optimal model, which would be appropriate in theory and practically more useful. The criterion can be computed approximately by using random numbers. We confirmed that the proposed criterion should lessen risk of choosing a parsimonious model wrongly.

    researchmap

  • ノンパラメトリック回帰による多次元構造の探索:推定方式の改良と実装

    Grant number：17700280  2005 - 2007

    日本学術振興会  科学研究費助成事業  若手研究(B)

    坂本 亘

    　 More details

    Grant amount：\3100000 （ Direct expense: \3100000 ）

    本研究は、非線形構造の探索・診断という観点からノンパラメトリック回帰の方法論を再整備し、ノンパラメトリック回帰をより強力な探索的データ解析の道具にすることを目的とした。とくに交互作用効果を含む多次元ノンパラメトリック回帰モデルの有用性を探った。
    前年度までに提案・開発した、多変量適応的回帰スプライン(MARS)における経験Bayes法による基底関数および節点の選定方式は、Friedman による従来の方式(一般化交差確認法の利用)での回帰構造の解釈などの難点を克服することを目標としている。これについて、本年度は以下のような研究を行った。
    1.変数寄与の測度の再検討
    回帰構造の解釈に必要となる、各々の説明変数の寄与(主効果・交互作用効果)の測度について、従来の「相対重要度」はかなりアドホックな定義であった。より合理的・包括的な測度として、分散分析などで用いられる平方和分解に類似した変動の分解に基づいて、条件付き分散を用いて定義することを検討した。
    2.シミュレーションなどによる性能評価
    前述の条件付き分散に基づく測度を用いて、従来の方式(Friedmanが提案した交差確認法などによる方法)に比べて、回帰構造、とくに交互作用効果を正しく抽出できることを実証した。

    researchmap

  • ノンパラメトリック回帰による非線形構造の探索とその実装

    Grant number：14780171  2002 - 2004

    日本学術振興会  科学研究費助成事業  若手研究(B)

    坂本 亘

    　 More details

    Grant amount：\3100000 （ Direct expense: \3100000 ）

    本研究の目標は,データの背後にある複雑な非線形構造を探索・抽出するための道具として,ノンパラメトリック回帰,とくに平滑化スプラインの有用性を実証し,その方法を実装したアプリケーションを開発することであった。
    本年度に実施した研究内容は以下のとおりである。
    1.応答のベキ変換による加法モデルの拡張
    加法モデルにおける仮定(加法性,分散均一性,正規性など)の妥当性を評価するために,ベキ加法化平滑化スプラインやベキ重み付き平滑化スプラインなどを提案し,Fortranプログラムによる実装を行った。応答のベキ変換パラメータを分散・平滑化パラメータと同時に最大周辺尤度法(経験Bayes法)によって選定する。ベキ加法化平滑化スプラインでは周辺尤度の正確な計算は困難であるため,その近似方式を提案した。本方式の近似精度,および本方式を用いた場合の加法関数の推定性能を,事例研究やシミュレーションを通じて評価し,推定されるベキ変換が非線形構造を考慮しながら加法性や分散均一性などの要件を達成するという妥当な結果を得ることができた。
    2.ABIC(赤池Bayes情報量基準)による最適なモデルの選定
    平滑化スプラインの線形混合モデルによる表現を利用することにより,包括的な階層型のモデル族を構築することが可能となる。モデルが非線形(ノンパラメトリック)成分を含むかどうかの診断は,線形混合モデルのランダム効果に関する診断に帰着され,必要となる分散パラメータの個数の選定にはABICを用いることができる。本方式の有用性を事例研究などにより確認した。

    researchmap

  • Refinement and improvement of microsimulation for colorectal cancer risk assessment

    Grant number：22K10559  2022.04 - 2026.03

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    加茂 憲一, 福井 敬祐, 坂本 亘

    　 More details

    Grant amount：\4030000 （ Direct expense: \3100000 、 Indirect expense：\930000 ）

    researchmap

  • がん対策推進基本計画の効果検証と目標設定に関する研究

    2014 - 2016

    厚生労働省  厚生労働科学研究費  H26-がん政策-一般-015

    加茂憲一(研究代表者), 田中純子, 高橋秀人, 坂本亘, 片野田耕太, 伊藤ゆり, 雑賀公美子, 松田 彩子, 伊森晋平

    　 More details

    Authorship：Coinvestigator(s)  Grant type：Competitive

    researchmap

  • Estimate on Regression Functions and ProbabilityDensity Functions

    Grant number：22540126  2010 - 2012

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    SHIRAHATA Shingo, SAKAMOTO Wataru, FUJIKI Mie, DOU Xiaoling

    　 More details

    Grant amount：\2340000 （ Direct expense: \1800000 、 Indirect expense：\540000 ）

    We proposed new procedures in the following two fields. First, we proposed robust estimator for simple linear regression and methods to analyze ultrasonic vocalization (USV) emitted from mice and rats. By Fourier transform ation of USV, we have functional data. We proposed methods how to eliminate errors, how to judge whether the extracted are really curves and how to classify the curves. Next, we constructed estimators of the integration of squared density function. We adopted kernel functions and U-statistics and showed that the asymptotic normality of the estimators and investigated several properties of them by computer simulations.

    researchmap

  • 関数データの解析法の開発とその応用の研究

    Grant number：17654024  2005 - 2007

    日本学術振興会  科学研究費助成事業  萌芽研究

    白旗 慎吾, 坂本 亘

    　 More details

    Grant amount：\3100000 （ Direct expense: \3100000 ）

    本研究では、気象データ、人間の成長データなど本来は関数として得られるべきであるが、観測の都合上離散時点で観測されたデータを関数データとし、その解析法を開発することを目的としている。
    関数データでは通常観測時点数が比較的多く、通常の多変量解析法は適用困難であり、まず元の関数(回帰関数)をできるだけ再現し、その後に判別解析、主成分分析などの種々の解析を行う。本年はその基本的問題である回帰関数の推定量、および、例えば人間の成長過程の解析に必要な速度関数(1回微分関数)・加速度(2回微分関数)の種々推定量の比較を行った。回帰関数の推定量の比較に関しては多くの研究がすでに行われているが微分関数の推定量の比較検討はほとんど行われていない。推定量としては、最もよく普及しているスプライン関数による区分的多項式で基底関数の係数を回帰関数と微分関数で別々に推定する方式と一度に推定する方式、kernel関数によるある種の加重和で通常の推定量を微分する方式と局所多項式モデルを考えその係数を用いる方式を考えた。ただし、解析は数学的には困難でコンピュータ・シミュレーションを多用した。比較する母回帰関数としては、微分の方が変動の激しい関数、変動がほとんど変わらない関数、変動が減少する関数を採用した。結果として、どの場合でもスプライン関数で基底関数の係数を回帰関数と微分関数で別個に推定する方式が最良であった。ただし計算量では一度に推定する方式の方が負荷が軽い。ただし、どの方式であれ、関数の定義域の境界近くで乱雑度が増し、精度が落ち欠点がある。そこで定義域の境界近くでより平滑な関数を得るために節点を調整する工夫を行った。結果は論文として投稿すべく準備中である。

    researchmap

  • Toward Sustainable Improvement in Quality of Life : Theoretical and Statistical Analysis on Policy Assessments

    Grant number：16203020  2004 - 2006

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    SHIMOMURA Ken-ichi, SHIRAHATA Shingo, FUKUSHIGE Mototsugu, YAMAJI Hidetoshi, HASHIMOTO Yoshizo, KOIKE Atsushi

    　 More details

    Grant amount：\39780000 （ Direct expense: \30600000 、 Indirect expense：\9180000 ）

    We conducted both theoretical and empirical analyses of policy assessments focusing on actual performances of economic policies. The analytical methods are economic theory, statistics, econometrics, and experimental economics. We regularly had meetings to check the processes and the results of works in progress, and finally published outputs of the researches.
    We form two research groups. One is a team to study environment, traffics and policy assessment, the members of which reviewed literatures of Japan and other countries about environmental and traffic problems such as garbage, industrial wastes, air pollutions, natural environment of sightseeing spots, and public transportation facilities. This group examined what kind of analytical methods and evaluation methods are suitable for these problems. Some of them carried out field surveys and hearing about the slow life and the recycling activities in the environmental policies of Italy. In addition, other members conducted cost-benefit analysis on the extension plan of the Osaka monorail, which is called "Saito project," with the choice experiment method.
    The other group specialized in the research of local public finance and the urban policy. They collected and analyzed data of sustainable growth of economies of remote islands and information disclosure problems of local governments. In particular, they employed questionnaire surveys to those who concern tourism of Amami Oshima Island and those who suffered from the Chuetsu earthquake. Some members also studied a tendency of convergence of income per capita based on data of the metropolitan area of Japan with Markov matrices. In the experimental economic analysis, other members showed that decentralized market mechanisms may not work out for unstable equilibria of perfect competition, or any types of equilibria of monopolistic competition. In the dynamic spatial general equilibrium analysis incorporated economies of scale, other members analyzed the influence of the traffic jam in the city part of the Netherlands from an aspect of the social economy and a living standard aspect, and investigated what influene congestions have on what type of industries.

    researchmap

  • Studies on statistical analysis process of lifetime information

    Grant number：15300091  2003 - 2005

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    SHIRAHATA Shingo, SAKAMOTO Wataru, KUROKI Manabu, SUGIMOTO Tomoyuki, OHTAKI Megu, OCHI Yoshimichi

    　 More details

    Grant amount：\14400000 （ Direct expense: \14400000 ）

    The purpose of this project is to develop statistical tools and methods which are useful to analyze data given in the medical fields, especially, useful to analyze lifetime (survival time or failure time) data and its related fields. If we interpret the lifetime as the time certain event occurs, then we may have data with the same structure in many fields of Reliability, Education, Psychology, Test Theory, Statistical Finance and so on. Hence the methods of lifetime analysis have enormous related fields. Lifetime data is taken by observing every living thing including human beings, animals, fishes and sso on, and due to their large variety the data is widely spread and skewed. Hence it is very difficult to apply classical parametric procedures where the normality of error distribution, the linearity of the mean structure and the homogeneity of error variance are assumed. Thus our attentions are focused on nonparametric procedures, semi-parametric methods, robust statistics and statistical graphics. Most of them are computer intensive methods.
    Head investigator and investigators studied statistical theory, methods and applications of the above procedures. Especially, we published papers and presented at several research meetings on (1)analysis of variance method for longitudinal data, (2)robust estimator based on the notion of depth, (3)decision of Wavelet bases functions by AIC, (4)diagnosis of the homogeneity of variances by spline smoothing, (5)construction of regression models by decision trees, (6)investigation of the properties of power transformations which are proposed to get normality, linearity and homogeneity of variances, (7)estimation of the causal effects, (8)developing computer intensive methods to analyze over-dispersed categorical data, (9)applications of the above procedures.
    Furthermore, we had scientific meetings five times. We had many participants including data analysts of private enterprizes. And we had exciting discussion useful both for research workers and data analysts.

    researchmap

  • RESEARCH OF STATISTICAL INFERENCE PROCESS IN THE HIGH-DIMENSIONAL INFORMATION PROCESSING

    Grant number：14208024  2002 - 2003

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    GOTO Masashi, SUGINOTO Tomoyuki, SAKAMOTO Wataru, SHIRAHARA Shingo, OCHI Yoshimiti, OHTAKI Megu

    　 More details

    Grant amount：\22750000 （ Direct expense: \17500000 、 Indirect expense：\5250000 ）

    The purpose of the project is to research and develop some statistical methodologies in process of the high-dimensional information processing which connects with human activities. Particularly, in the process we have focused on date-adaptive or information environmental-adaptive inference. Further, in the process of statistical date analysis, we provided some productive findings that were unsighted in date investigations and reifications.
    Main productive results involved tree structured approaches, statistical transformations, statistical graphics, date adaptive distributions, some mixed models, and variants of the proportional hazard model etc. In the project research, we could obtain the following main results and some productive findings.
    We have provided the process of date-adaptive inference and the comprehensive approaches systematically in the high-dimensional processing, particularly, fields of the date science.
    In the statistical graphics, theories, methods, applications and evaluations were systematically provided and the data-adaptive graphics were proposed and evaluated though case-studies and simulations.
    Analytical methods of incomplete data were provided with respect to recent developments and widely applied in medical fields.
    Survival CART and longitudinal MARS (L-MARS) were proposed, developed, and applied to some data cited in literatures of medical and pharmaceutical fields.

    researchmap

  • 非線形構造の探索・抽出のためのノンパラメトリック回帰とその有用性の研究

    Grant number：12780177  2000 - 2001

    日本学術振興会  科学研究費助成事業 奨励研究(A)  奨励研究(A)

    坂本 亘

    　 More details

    Grant amount：\1700000 （ Direct expense: \1700000 ）

    ノンパラメトリック回帰の代表的な方法であるスプライン平滑化では,平滑化パラメータが推定関数の滑らかさを制御する.本研究では,制限付き最尤推定法(REML)による平滑化パラメータの選定方式に着目し,非線形構造の探索・抽出という観点からその性能評価を行った.そして,REMLによる選定方式を用いることで,スプライン平滑化が探索的データ解析の有用な道具となる可能性を追求してきた.
    13年度の研究で得られた知見・成果は以下のとおりである.
    1.シミュレーションによるREMLの性能評価
    REMLによる非線形構造や相関構造の抽出能力,さらに関数および分散・相関パラメータの推定性能を評価した.その結果,REMLは非線形構造をほぼ適切に抽出し,相関がある場合にもこれを適切に検出することができること,さらにREMLは標本サイズが比較的小さい場合にも有用であることがわかった.平滑化スプラインとREMLの組み合わせにより,ノンパラメトリック回帰は非線形構造の探索・診断を行うための道具としての有用性をもつといえる.
    今後は以上の成果について学会発表や投稿論文による報告を行う予定である.加法モデルや交互作用モデルなど種々のモデルヘのREMLの適応とその評価についても今後の検討課題としたい.
    2.非正規型ノンパラメトリック回帰モデルヘのREMLの適用についての考察
    非正規型平滑化スプライン・モデルを一般化線形混合効果モデルによって表現し,回帰関数を求めるための反復方程式に基づいて構成される近似的な制限付き対数尤度を最大化する.簡単な数値実験を行ったところ,観測が同じ説明変数値で反復される場合にはREMLによって平滑化パラメータが良好に選定されるのに対して,異なる説明変数値において観測される場合にはやや滑らかな関数を推定することがわかった.
    今後は上記の問題点の改良を行い,より包括的な性能評価を行う予定である.

    researchmap

  • 繰り返し全数検査とそのパラメータ推定法の研究

    Grant number：11878047  1999 - 2000

    日本学術振興会  科学研究費助成事業  萌芽的研究

    白旗 慎吾, 坂本 亘, 安芸 重雄, 後藤 昌司

    　 More details

    Grant amount：\2100000 （ Direct expense: \2100000 ）

    1.品質検査の対象となるロットに含まれる不良品個数をM、1回の検査で不良品が検出される確率をθ、1回の検査のコストをcとする。本研究ではロットに含まれる製品の数は極めて多く、不良品の個数は相対的には少ないことを仮定している。検査の目的は合理的なコストで可能な限り不良品を除去すること、および残存不良品個数を精度良く推定することである。
    2.ロットの現状を把握するためにはT回の全数検査によりM、θを推定する必要がある。推定方式として単純最小2乗法、重み付き最小2乗法、最尤法、モーメント法を比較し、精度としては最尤法が最も良く、ただし多くの場合に計算の容易な単純最小2乗法も捨てがたいことが分かった。
    3.もちろんすべての不良品を発見することが望ましい。また、検査は終わらなければならない。実際的ないくつかの停止方式でのコスト、検査回数等を求めた。実際に行われている検査回数は少なすぎることを指摘した。これはすでに論文として発表している。
    4.不良のタイプが複数の場合は発見確率θがそれぞれで異なるが、2,3の方式を組み合わせれば推定、計算は容易である。
    5.検査に物理的な刺激が加わる場合は、検査により不良品が追加発生されることがある。その場合の物理モデルは知られていない。追加発生の確率として、ポアソン分布、負の2項分布などのモデルの当てはめを行っているが、データにうまく当てはまるモデルはまだ見つかっていない。

    researchmap

  • Study on Theory of Nonlinear Statistical Models and Its Applications

    Grant number：09304024  1997 - 1999

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    SHIRAHATA Shingo

    　 More details

    Grant amount：\20000000 （ Direct expense: \20000000 ）

    (1). The objects of this project are (A) to study theory and methods on nonlinear statistics by the head investigator and the investigators and (B) to hold meetings on topics of nonlinear statistics in order to have discussion with each other and with researchers outside our group.
    (2). On (A), the head and the investigators studied several topics. Many of them are published in several scientific journals or presented at domestic/international meetings. The details of them are listed in the written report and some selected works are at references of this report.
    (3). On (B), we held meetings seven times. The titles of our meetings are as followes.
    (1). First meeting on nonlinear statistical models and its applications at Kure.
    (2). Second meeting on nonlinear statistical models and its applications at Oita.
    (3) Meeting on nonlinear problem and experimental design at Hiroshima University.
    (4) Meeting on nonparametrics, nonlinear models and simulation at Seikei University.
    (5) Meeting on nonlinear statistical models and data analysis at Toba.
    (6) Meeting on nonlinear statistical models and computer at Kanazawa University.
    (7) Meeting on experiment data and nonlinear statistical models at Matsuyama.
    The topics presented at these meetings are from theoretical statistics to analysis of practical data having nonlinear structure. Some of them are on established results and some are on unsolved problems. Most of them are on computer intensive methods such as neural networks, determination of smoothing parameter and computation points on spline regression analysis, generation of random numbers, growth curve model, nonlinear models at medical statistics, statistical graphics and so on.

    researchmap

  • Research of Statistical Data Analysis Process Based on Harmonaization of Experimental and Olservational Studies

    Grant number：09558024  1997 - 1999

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    GOTO Masashi, TAGO Yoshio, OCHI Yoshimichi, SHIRAHATA Shingo, SAKAMOTO Wataru, INAGAKI Nobuo

    　 More details

    Grant amount：\12100000 （ Direct expense: \12100000 ）

    The purposes of the project are to research and develop some methodologies which can be used in both experimental and observational studies. Particularly, in experimental studies we have focused on a posteriori analysis of data in each experiment from the view of observational studies. Further, in observational studies, we provided some methods and approaches of cause-effect inference, which include tree structured methods, i.e., CART, Survival CART and MARS. In the project research, we could obtain the following results and some productive findings :
    We have provided the process of evaluating quality of experimental studies and re-investigated cycle of experiments, especially diagnosis of experimental studies.
    As a posteriori analysis of the experimental data, we have provided inference methods from "samples to individuals", for instance, from "medical treatments (drugs) to disease" to "cure (drugs) to patient" based by constructing individual profiles based on tree structured methods.
    In survival analysis, we have developed adjusted proportional hazard model which took account of long survivors for ordinary model, and applied the model to cancer data. Consequently, the model had exhaustive and data-adaptive properties, so it was shown to have useful applications in medical and/or clinical studies.
    For recent issues of ICH in clinical trials, we have proposed some models and approaches to bridging between concurrent trial and foreign clinical trials, and shown the usefulness of usefulness of the approaches by applying to some practical data.
    Particularly, inference of dose-response relationships have been widely and systematically investigated, some models and/or approaches have been proposed from the view of estimation of cumulative distribution function, and the utility of the models and/or approaches have been shown by conducting many simulations and trials to literature data.

    researchmap

  • Research of Statistical Transformation Methodology

    Grant number：09640266  1997 - 1998

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    GOTO Masashi, SAKAMOTO Wataru, TANIGUCHI Masanobu, SHIRAHATA Shingo, ETO Toshihisa, OHTAKI Megu

    　 More details

    Grant amount：\2900000 （ Direct expense: \2900000 ）

    The purposes of the project are to research some types and methods of parametric and non-parametric transformations of data, to evaluate performances for practical uses, and to develop their extensions. In the project research, we could obtain the following results and some productive findings :
    We have proposed three extended power-transformations, namely Double-power Normal Transformation (DPNT). Double-power Additive Transformation (DPAT), and Double-power Weighted Transformation (DPWT). Further, we evaluated performances of the proposed transformations by applying to some examples cited in literatures and conducting simulations experiments. These transformations have shown better performances than ordinary power transformation, in normality and homogeneity of observation, and additivity of model.
    A modified power transformation was proposed to ordinary power transformation. This transformation is completely equal to identity transformation when transformation of data is not necessary. Incidentally, the ordinary power transformation was nearly equal to identity transformation in such case.
    We have shown inference approach of the power-normal distribution based on grouped observations and their extensive applications. These results was useful in analyses of practical data, especially biomedical and behaviormetric data. Further, the inforence procedure was extended to case which both grouped and ungrouped observations were included.
    Non-parametric transformation ACE were extended to combine it with SIR and some performances of the approach was evaluated. The computer program of the approach was also developed and produced to the research on many follows.
    As a control of the power normal distribution, we have investigated log-gamma distribution and evaluated some its performances relative to the power normal distribution of fitting to some practical data, and further have shown extensive applications to medical field.
    We have investigated possibility of transforming qualitative data to their quantitative forms by using the power transformation. Particularly, we evaluated the appropriateness of log-transformation to data which had Poisson distribution.

    researchmap

▼display all

 

Class subject in charge

  • Simulation Statistics （2024academic year） Late  - 火7～8

  • Technical English （2024academic year） 3rd and 4th semester  - [第３学期]水3～4, [第４学期]水1～2

  • Basic of Information Technology, Electrical Engineering, and Mathematical and Data Sciences （2024academic year） 1st semester  - 水1～2

  • Basic Mathematical and Data Sciences （2024academic year） Third semester  - 木5～6

  • Mathematical and Data Sciences（Advanced） （2024academic year） Fourth semester  - 火1～2

  • Mathematical Statistics （2024academic year） 1st semester  - 火1～2,金3～4

  • Mathematical Statistics Ⅱ-1 （2024academic year） Third semester  - 火3,金3

  • Mathematical Statistics Ⅱ-2 （2024academic year） Third semester  - 火4,金4

  • Advanced Study （2024academic year） Other  - その他

  • Topics in Statistical Modeling for Environmental Science A （2024academic year） Second semester  - その他

  • Basic Statistical Data Analysis （2024academic year） 1st semester  - 月5～6,木1～2

  • Seminar in Statistical Data Analysis A （2024academic year） Year-round  - その他

  • Seminar in Statistical Data Analysis B （2024academic year） Year-round  - その他

  • Advanced Seminar in Statistical Data Analysis （2024academic year） Year-round  - その他

  • Topics in Statistical Data Analysis A （2024academic year） Second semester  - その他

  • Statistical Modeling （2024academic year） Third semester  - 火3～4,金3～4

  • Advanced Statistical Modeling （2024academic year） Late  - その他

  • Statistics I （2024academic year） Fourth semester  - 火1～2

  • Statistics Ⅱ （2024academic year） 1st semester  - 月5～6,木1～2

  • Internship （2023academic year） Summer concentration  - その他

  • Internship （2023academic year） Summer concentration  - その他

  • Multivariate Distribution Theory （2023academic year） Late  - 火5～6

  • Technical English （2023academic year） 3rd and 4th semester  - [第３学期]水3～4, [第４学期]水1～2

  • Basic of Information Technology, Electrical Engineering, and Mathematical and Data Sciences （2023academic year） 1st semester  - 水1～2

  • Basic Mathematical and Data Sciences （2023academic year） Third semester  - 木5～6

  • Mathematical and Data Sciences（Advanced） （2023academic year） Fourth semester  - 火1～2

  • Mathematical Statistics （2023academic year） 1st semester  - 火1～2,金3～4

  • Mathematical Statistics Ⅱ-1 （2023academic year） Third semester  - 火3,金3

  • Mathematical Statistics Ⅱ-2 （2023academic year） Third semester  - 火4,金4

  • Mathematical Statistics I-1 （2023academic year） 1st semester  - 火1,金3

  • Mathematical Statistics I-2 （2023academic year） 1st semester  - 火2,金4

  • Advanced Study （2023academic year） Other  - その他

  • Special Research （2023academic year） Year-round  - その他

  • Advanced Environmental Influence Research （2023academic year） Late  - その他

  • Seminar on Environmental Statistics （2023academic year） Prophase  - その他

  • Seminar in Environmental Statistics （2023academic year） Late  - その他

  • Seminar on Environmental Statistics （2023academic year） Late  - その他

  • Seminar in Environmental Statistics （2023academic year） Prophase  - その他

  • Basic Statistical Data Analysis （2023academic year） 1st semester  - 月5～6,木1～2

  • Seminar in Statistical Data Analysis A （2023academic year） Year-round  - その他

  • Seminar in Statistical Data Analysis A （2023academic year） Year-round  - その他

  • Seminar in Statistical Data Analysis B （2023academic year） Year-round  - その他

  • Seminar in Statistical Data Analysis B （2023academic year） Year-round  - その他

  • Advanced Seminar in Statistical Data Analysis （2023academic year） Year-round  - その他

  • Advanced Statistical Data Analysis （2023academic year） Late  - その他

  • Statistical Modeling （2023academic year） Third semester  - 火3～4,金3～4

  • Advanced Statistical Modeling （2023academic year） Late  - その他

  • Statistical Modeling Theory （2023academic year） Late  - 火5～6

  • Statistics I （2023academic year） Fourth semester  - 火1～2

  • Statistics Ⅱ （2023academic year） 1st semester  - 月5～6,木1～2

  • Bayesian Statistical Analysis （2022academic year） Late  - 火5～6

  • Basic of Information Technology, Electrical Engineering, and Mathematical and Data Sciences （2022academic year） 1st semester  - 水1～2

  • Advanced Mathematical Science in Liberal Arts （2022academic year） Third semester  - 月5～6

  • Basic Mathematical and Data Sciences （2022academic year） Third semester  - 木5～6

  • Mathematical and Data Sciences（Advanced） （2022academic year） Fourth semester  - 火1～2

  • Mathematical Optimization （2022academic year） Prophase  - 火5～6

  • Mathematical Statistics Ⅱ-1 （2022academic year） 1st semester  - 月1～2

  • Mathematical Statistics Ⅱ-2 （2022academic year） Second semester  - 月1～2

  • Mathematical Statistics I-1 （2022academic year） special  - その他

  • Mathematical Statistics I-2 （2022academic year） special  - その他

  • Special Research （2022academic year） Year-round  - その他

  • Advanced Environmental Influence Research （2022academic year） Late  - その他

  • Topics in Statistical Modeling for Environmental Science A （2022academic year） Summer concentration  - その他

  • Topics in Statistical Modeling for Environmental Science B （2022academic year） Summer concentration  - その他

  • Seminar on Environmental Statistics （2022academic year） Prophase  - その他

  • Seminar in Environmental Statistics （2022academic year） Late  - その他

  • Seminar on Environmental Statistics （2022academic year） Late  - その他

  • Seminar in Environmental Statistics （2022academic year） Prophase  - その他

  • Probability and Statistics 2 （2022academic year） Fourth semester  - 火1～2

  • Introduction to Stochastic Processes （2022academic year） Late  - 月3～4

  • Basic Statistical Data Analysis （2022academic year） 1st semester  - 月5～6,木1～2

  • Advanced Statistical Data Analysis （2022academic year） Late  - その他

  • Statistics I （2022academic year） Fourth semester  - 火1～2

  • Statistics Ⅱ （2022academic year） 1st semester  - 月5～6,木1～2

  • Statistics Ⅱ （2022academic year） 1st semester  - 月5～6,木1～2

  • Computational Statistics B-1 （2022academic year） Third semester  - 火3～4

  • Computational Statistics B-2 （2022academic year） Fourth semester  - 火3～4

  • Seminar on Statistical Science （2021academic year） Fourth semester  - 月1,月2

  • Multivariate Distribution Theory （2021academic year） Prophase  - 月5～6

  • Basic of Information Technology, Electrical Engineering, and Mathematical and Data Sciences （2021academic year） 1st semester  - 水1～2

  • Basic Mathematical and Data Sciences （2021academic year） Third semester  - 木5～6

  • Mathematical and Data Sciences（Advanced） （2021academic year） Fourth semester  - 火1,火2

  • Mathematical Statistics Ⅱ-1 （2021academic year） 1st semester  - 月1～2

  • Mathematical Statistics Ⅱ-2 （2021academic year） Second semester  - 月1～2

  • Mathematical Statistics Ⅱ （2021academic year） 1st and 2nd semester  - 月1～2

  • Special Research （2021academic year） Year-round  - その他

  • Advanced Environmental Influence Research （2021academic year） Late  - その他

  • Seminar on Environmental Statistics （2021academic year） Prophase  - その他

  • Seminar in Environmental Statistics （2021academic year） Late  - その他

  • Seminar on Environmental Statistics （2021academic year） Late  - その他

  • Seminar in Environmental Statistics （2021academic year） Prophase  - その他

  • Probability and Statistics 2 （2021academic year） Fourth semester  - 火1,火2

  • Seminar on Statistical Science （2021academic year） Fourth semester  - 月1～2

  • Elementary Statistical Science （2020academic year） Third semester  - 火1,火2

  • Career Education （2020academic year） Fourth semester  - 月1,月2,月3

  • Career Education （2020academic year） Fourth semester  - 月1,月2,月3

  • Bayesian Statistical Analysis （2020academic year） Prophase  - 月2,月3

  • Elementary Statistical Science （2020academic year） Third semester  - 火1,火2

  • Basic Mathematical and Data Sciences （2020academic year） Third semester  - 月1,月2

  • Mathematical Statistics Ⅱ-1 （2020academic year） 1st semester  - 月6,月7

  • Mathematical Statistics Ⅱ-2 （2020academic year） Second semester  - 月6,月7

  • Mathematical Statistics Ⅱ （2020academic year） 1st and 2nd semester  - 月6,月7

  • Special Research （2020academic year） Year-round  - その他

  • Advanced Environmental Influence Research （2020academic year） Late  - その他

  • Seminar on Environmental Statistics （2020academic year） Prophase  - その他

  • Seminar in Environmental Statistics （2020academic year） Late  - その他

  • Seminar on Environmental Statistics （2020academic year） Late  - その他

  • Seminar in Environmental Statistics （2020academic year） Prophase  - その他

  • Linear Algebra I （2020academic year） 1st semester  - 火3,金1,金2

  • Linear Algebra I （2020academic year） 1st semester  - 火3,金1,金2

▼display all

 

Academic Activities

  • Associate Editor, Japanese Journal of Statistics and Data Science International contribution

    Role(s)：Peer review

    2023.1.1

    　More details

    Type：Peer review 

    researchmap

  • Computational Statistics: Editor-in-Chief

    Role(s)：Planning, management, etc.,　Peer review

    2018.7.1 - 2020.12.31

    　More details

    Type：Peer review 

    researchmap

  • 2015年度統計関連学会連合大会（運営委員長）

    Role(s)：Planning, management, etc.

    2015.9.6 - 2015.9.9

    　More details

    Type：Competition, symposium, etc. 

    researchmap

  • Editor, Journal of the Japanese Society of Computational Statistics

    Role(s)：Planning, management, etc.,　Peer review

    2015.1.1 - 2018.4.30

    　More details

    Type：Academic society, research group, etc. 

    researchmap

  • Data Science, Statistics and Visualization

    Role(s)：Planning, management, etc.

    2019.8.13 - 2019.8.15

    　More details

    Type：Competition, symposium, etc. 

    researchmap

  • 日本行動計量学会 岡山地域部会 世話人

    Role(s)：Planning, management, etc.

    2018.4 - 2021.3

    　More details

    Type：Academic society, research group, etc. 

    researchmap

  • Coordinating Editor, Japanese Journal of Statistics and Data Science

    Role(s)：Planning, management, etc.,　Peer review

    2018.1.1 - 2018.12.31

    　More details

    Type：Academic society, research group, etc. 

    researchmap

  • Computational Statistics: Co-editor

    Role(s)：Planning, management, etc.,　Peer review

    2015.4.1 - 2018.6.30

    　More details

  • 行動計量学 編集委員

    Role(s)：Planning, management, etc.,　Peer review

    2015.4 - 2018.3

    　More details

    Type：Academic society, research group, etc. 

    researchmap

  • Behaviormetrika

    Role(s)：Planning, management, etc.,　Peer review

    2012.4 - 2015.3

    　More details

    Type：Academic society, research group, etc. 

    researchmap

  • 計算機統計学 編集委員

    Role(s)：Planning, management, etc.,　Peer review

    2009.1 - 2014.12

    　More details

    Type：Academic society, research group, etc. 

    researchmap

  • Joint Meeting of 4th World Conference of the IASC and 6th Conference of the Asian Regional Section of the IASC on Computational Statistics & Data Analysis

    Role(s)：Planning, management, etc.

    2008.12

    　More details

    Type：Competition, symposium, etc. 

    researchmap

  • Computational Statistics: Associate Editor

    Role(s)：Peer review

    2008.5.1 - 2015.3.31

    　More details

    Type：Peer review 

    researchmap

  • International Conference on New Trends in Computational Statistics with Biomedical Applications

    Role(s)：Planning, management, etc.

    2001.8

    　More details

    Type：Competition, symposium, etc. 

    researchmap

▼display all