• Title/Summary/Keyword: Local statistics

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Assessing Local Influence in Linear Regression Models with Second-Order Autoregressive Error Structure (이차 자기회구오차 구조를 갖는 선형회귀모형의 자료영향도 평가)

  • Kim, Soon-Kwi;Lee, Young-Hoon;Jeong, Dong-Bin
    • Journal of Korean Society for Quality Management
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    • v.28 no.2
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    • pp.57-69
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    • 2000
  • This paper discusses the local influence approach to the linear regression models with AR(2) errors. Diagnostics for the linear regression models with AR(2) errors are proposed and developed when simultaneous perturbations of the response vector are allowed- That is, the direction of maximum curvature of local influence analysis is obtained by studying the curvature of a surface associated with the overall discrepancy measure.

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Denosing of images using locally adaptive wiener filter in wavelet domain (웨이브렛 변환 영역에서의 국부적응 Wiener 필터에 의한 영상 신호의 잡음 제거)

  • 장익훈;김남철
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.12
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    • pp.2772-2782
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    • 1997
  • In this paepr, a Wiener filtering method in wavelet domain is proposed for restoring an image corrupted by additive white noise. The proposed method utilizes the characteristics of wavelet transform signals and the local statistics of each subband. When estimating the local statistics in each subband, the size of filter window is varied according to each scale. At this point, the local statistics in each wavelet subband is estimated only by using pixedls which have similar statistical property. Experimental results show that the proposed method has better performance over the conventional Lee filter with a window of fixed size.

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Influence diagnostics for skew-t censored linear regression models

  • Marcos S Oliveira;Daniela CR Oliveira;Victor H Lachos
    • Communications for Statistical Applications and Methods
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    • v.30 no.6
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    • pp.605-629
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    • 2023
  • This paper proposes some diagnostics procedures for the skew-t linear regression model with censored response. The skew-t distribution is an attractive family of asymmetrical heavy-tailed densities that includes the normal, skew-normal and student's-t distributions as special cases. Inspired by the power and wide applicability of the EM-type algorithm, local and global influence analysis, based on the conditional expectation of the complete-data log-likelihood function are developed, following Zhu and Lee's approach. For the local influence analysis, four specific perturbation schemes are discussed. Two real data sets, from education and economics, which are right and left censoring, respectively, are analyzed in order to illustrate the usefulness of the proposed methodology.

A case study on the selection of representative statistics for systematic management of administrative statistics (행정통계의 체계적 관리를 위한 대표적 통계항목 선정 사례연구)

  • Lee, Kang-Jin;Kim, Min-Kyoung;Ahn, Jeong-Yong;Choi, Kyoung-Ho
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.1
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    • pp.63-70
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    • 2012
  • In spite of growing demand for the region specific statistics, due to the increase in the cost of making out statistics and other reasons, utilizing survey statistics has limitation on coping with it. Thus, administrative statistics could be a feasible option. In this study, we selected "representative statistics", which are frequently used in establishing regional policy and reflect regional characteristics, among the Jeollabuk-do's administrative statistics. And we suggested the way to enhance quality and credential of the administrative statistics by using systematic management. As a result, we selected 45 statistics for Jeollabuk-do's "representative statistics". The reason that we raise the issue on the necessity of selecting "representative statistics" and specify its selection process is to give guidance to systematic management and efficient utilization of the local government's administrative statistics.

Local Centers of the Social Network

  • Huh, Myung-Hoe
    • Communications for Statistical Applications and Methods
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    • v.18 no.2
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    • pp.213-217
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    • 2011
  • For the social network of n nodes, one might be interested in finding k nodes to disseminate the information as quickly as possible or to identify key nodes of high "local centrality". I propose two algorithms for determining k "local centers" of the network and work on a real case.

A Study on the Sample Design for the Labor Statistics - Monthly Labor Statistics Survey and Labor Demand Survey - (노동통계조사를 위한 표본설계 - 매월노동통계조사, 노동력수요동향조사를 중심으로 -)

  • 이기재;전종우
    • The Korean Journal of Applied Statistics
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    • v.10 no.2
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    • pp.215-226
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    • 1997
  • The purpose of the labor statistics survey is to collect materials on employment, wages and the working time and to analyze the trend of the labor situation. in this research, the stratification variables are industry and the size of establishment. The sample are selected by stratified one stage sampling method in order to produce the reliable estimates of labor statistics. For local labor statistics, we design the sample survey using the city and province as sub-population. So we are able to produce the local area estimates of labor statistics with respect to industry and the size of establishment.

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A Study on Data Base of Region Statistics (지역통계 데이타 베이스 구축방안)

  • Lee, Hwa-Young;Lee, Hee-Choon;Hong, Ki-Hak
    • Journal of Korean Society for Quality Management
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    • v.22 no.1
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    • pp.179-187
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    • 1994
  • This study suggests a data base scheme of region statistics whose demand has been rapidly increased as the local self-governing body is introduced in Korea. A program for the region statistics management(registration, reference, modification, deletion) is developed and it can be used by personal computer users.

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Spatial Clustering Method Via Generalized Lasso (Generalized Lasso를 이용한 공간 군집 기법)

  • Song, Eunjung;Choi, Hosik;Hwang, Seungsik;Lee, Woojoo
    • The Korean Journal of Applied Statistics
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    • v.27 no.4
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    • pp.561-575
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    • 2014
  • In this paper, we propose a penalized likelihood method to detect local spatial clusters associated with disease. The key computational algorithm is based on genlasso by Tibshirani and Taylor (2011). The proposed method has two main advantages over Kulldorff's method which is popoular to detect local spatial clusters. First, it is not needed to specify a proper cluster size a priori. Second, any type of covariate can be incorporated and, it is possible to find local spatial clusters adjusted for some demographic variables. We illustrate our proposed method using tuberculosis data from Seoul.

Image Enhancement Using Adaptive Weighted Sigma Filter (적응비중화 시그마필터에 의한 영상향상)

  • Hwang, Jae-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.2 s.314
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    • pp.19-26
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    • 2007
  • In the sigma filter, there is a specialized neighbours distribution scheme in which the sigma value is computed from local statistics. It is designed to modify a standard average filter to preserve edges. However this filter is vulnerable to details-enhancement and conventional sigma approaches have been focused on denoising, not enhancing the characteristic area. This paper proposes an adaptive image enhancement algorithm using local statistics and functional synthesis which are utilized for adaptive realization of the enhancement, so that not only image noise may be smoothed but also details may be enhanced. For the local adaptation, parameters are estimated and weighted at each moving window that satisfy the criteria. The experimental results illuminates the effectiveness of the proposed method.

An Adaptive Noise Detection and Modified Gaussian Noise Removal Using Local Statistics for Impulse Noise Image (국부 통계 특성을 이용한 임펄스 노이즈 영상의 적응적 노이즈 검출 및 변형된 형태의 Gaussian 노이즈 제거 기법)

  • Nguyen, Tuan-Anh;Song, Won-Seon;Hong, Min-Cheol
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.11a
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    • pp.179-181
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    • 2009
  • In this paper, we propose an adaptive noise detection and modified Gaussian removal algorithm using local statistics for impulse noise. In order to determine constraints for noise detection, the local mean, variance, and maximum values are used. In addition, a modified Gaussian filter that integrates the tuning parameter to remove the detected noises. Experimental results show that our method is significantly better than a number of existing techniques in terms of image restoration and noise detection.

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