Small area estimation for grouped data

This paper proposes a new model-based approach to small area estimation for grouped data or frequency data, which is often available from sample surveys. Grouped data contains information on frequencies of some pre-specified groups in each area, for example the numbers of households in the income classes, and thus provides more detailed insight about small areas than area level aggregated data. A direct application of the widely used small area methods, such as the Fay-Herriot model for area level data and nested error regression model for unit level data, is not appropriate since they are not designed for grouped data. The newly proposed method assumes that the unobserved unit level quantity of interest follows a linear mixed model with the random intercepts and dispersions after some transformation. Then the probabilities that a unit belongs to the groups can be derived and are used to construct the likelihood function for the grouped data given the random effects, which is in the form of the multinomial likelihood. The unknown model parameters (hyperparameters) are estimated by a newly developed Monte Carlo EM algorithm using an efficient importance sampling. The empirical best predicts (empirical Bayes estimates) of small area parameters can be calculated by a simple Gibbs sampling algorithm. The numerical performance of the proposed method is illustrated based on the model-based and design-based simulations. In the application to the city level grouped income data of Japan, we complete the patchy maps of the Gini coefficient as well as mean income across the country

混合効果モデルにおける変数選択問題と小地域推定への応用

学位の種別: 論文博士審査委員会委員 : （主査）東京大学教授 久保川 達也, 東京大学教授 國友 直人, 東京大学教授 矢島 美寛, 東京大学教授 大森 裕浩, 東京大学教授 下津 克己, 東京大学准教授 加藤 賢悟University of Tokyo(東京大学

Photoluminescence Enhancement of β-FeSi2 Nanocrystals Controlled by Transport of Holes in Cu-doped n-type Si Substrates

We have investigated PL behavior of β-FeSi2 nanocrystals controlled by transport of holes in Cu-doped n-type Si substrates. PL enhancement was observed and PCI-PL measurements revealed that PL enhancement was attributed to a transport process of holes with a larger time constant in Cu-doped n-Si substrate in which an interval trap process is controlled by Cu doping.International Conference and Summer School on Advanced Silicide Technology 2014, July 19–21, 2014, Tokyo, Japa