• Title/Summary/Keyword: spatial statistics

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Categorical Data Analysis by Means of Echelon Analysis with Spatial Scan Statistics

  • Moon, Sung-Ho
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.1
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    • pp.83-94
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    • 2004
  • In this study we analyze categorical data by means of spatial statistics and echelon analysis. To do this, we first determine the hierarchical structure of a given contingency table by using echelon dendrogram then, we detect candidates of hotspots given as the top echelon in the dendrogram. Next, we evaluate spatial scan statistics for the zones of significantly high or low rates based on the likelihood ratio. Finally, we detect hotspots of any size and shape based on spatial scan statistics.

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Detection of Hotspots for Geospatial Lattice Data

  • Moon, Sung-Ho;Kim, Jong-Duk
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.1
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    • pp.131-139
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    • 2006
  • Statistical analyses for spatial data are important features for various types of fields. Spatial data are taken at specific locations or within specific regions and their relative positions are recorded. Lattice data are synoptic observation covering an entire spatial region, like cancer rates corresponding to each county in a state. The main purpose of this paper is to detect hotspots for the region with significantly high or low rates. Kulldorff(1997) detected hotspots based on circular spatial scan statistics. We propose a new method to find any shapes of hotspots by use of echelon analysis with spatial scan statistics.

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A STUDY ON THE EFFECT OF POWER TRANSFORMATION IN SPATIAL STATISTIC ANALYSIS

  • LEE JIN-HEE;SHIN KEY-IL
    • Journal of the Korean Statistical Society
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    • v.34 no.3
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    • pp.173-183
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    • 2005
  • The Box-Cox power transformation is generally used for variance stabilization. Recently, Shin and Kang (2001) showed, under the Box-Cox transformation, invariant properties to the original model under the large mean and relatively small variance assumptions in time series analysis. In this paper we obtain some invariant properties in spatial statistics. Spatial statistics, Invariant Property, Variogram, Box-Cox power Transformation.

Spatial-Temporal Modelling of Road Traffic Data in Seoul City

  • Lee, Sang-Yeol;Ahn, Soo-Han;Park, Chang-Yi;Jeon, Jong-Woo
    • Journal of the Korean Data and Information Science Society
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    • v.13 no.2
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    • pp.261-270
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    • 2002
  • Recently, the demand of the Intelligent Transportation System(ITS) has been increased to a large extent, and a real-time traffic information service based on the internet system became very important. When ITS companies carry out real-time traffic services, they find some traffic data missing, and use the conventional method of reconstructing missing values by calculating average time trend. However, the method is found unsatisfactory, so that we develop a new method based the spatial and spatial-temporal models. A cross-validation technique shows that the spatial-temporal model outperforms the others.

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Sample Based Algorithm for k-Spatial Medians Clustering

  • Jin, Seo-Hoon;Jung, Byoung-Cheol
    • The Korean Journal of Applied Statistics
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    • v.23 no.2
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    • pp.367-374
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    • 2010
  • As an alternative to the k-means clustering the k-spatial medians clustering has many good points because of advantages of spatial median. However, it has not been used a lot since it needs heavy computation. If the number of objects and the number of variables are large the computation time problem is getting serious. In this study we propose fast algorithm for the k-spatial medians clustering. Practical applicability of the algorithm is shown with some numerical studies.

Bayes Inference for the Spatial Bilinear Time Series Model with Application to Epidemic Data

  • Lee, Sung-Duck;Kim, Duk-Ki
    • The Korean Journal of Applied Statistics
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    • v.25 no.4
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    • pp.641-650
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    • 2012
  • Spatial time series data can be viewed as a set of time series simultaneously collected at a number of spatial locations. This paper studies Bayesian inferences in a spatial time bilinear model with a Gibbs sampling algorithm to overcome problems in the numerical analysis techniques of a spatial time series model. For illustration, the data set of mumps cases reported from the Korea Center for Disease Control and Prevention monthly over the years 2001~2009 are selected for analysis.

Model for the Spatial Time Series Data

  • Lim, Seongsik;Cho, Sinsup;Lee, Changsoo
    • Journal of Korean Society for Quality Management
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    • v.24 no.1
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    • pp.137-145
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    • 1996
  • We propose a model which is useful for the analysis of the spatial time series data. The proposed model utilized the linear dependences across the spatial units as well as over time. Three stage model fitting procedures are suggested and the real data is analyzed.

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A Spatial Statistical Approach to Residential Differentiation (I): Developing a Spatial Separation Measure (거주지 분화에 대한 공간통계학적 접근 (I): 공간 분리성 측도의 개발)

  • Lee, Sang-Il
    • Journal of the Korean Geographical Society
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    • v.42 no.4
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    • pp.616-631
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    • 2007
  • Residential differentiation is an academic theme which has been given enormous attention in urban studies. This is due to the fact that residential segregation can be seen as one of the best indicators for socio-spatial dialectics occurring on urban space. Measuring how one population group is differentiated from the other group in terms of residential space has been a focal point in the residential segregation studies. The index of dissimilarity has been the most extensively used one. Despite its popularity, however, it has been accused of inability to capture the degree of spatial clustering that unevenly distributed population groups usually display. Further, the spatial indices of segregation which have been introduced to edify the problems of the index of dissimilarity also have some drawbacks: significance testing methods have never been provided; recent advances in spatial statistics have not been extensively exploited. Thus, the main purpose of the research is to devise a spatial separation measure which is expected to gauge not only how unevenly two population groups are distributed over urban space, but also how much the uneven distributions are spatially clustered (spatial dependence). The main results are as follows. First, a new measure is developed by integrating spatial association measures and spatial chi-square statistics. A significance testing method based on the generalized randomization test is also provided. Second, a case study of residential differentiation among groups by educational attainment in major Korean metropolitan cities clearly shows the applicability of the analytical framework presented in the paper.

Interpretation of Real Information-missing Patch of Remote Sensing Image with Kriging Interpolation of Spatial Statistics

  • Yiming, Feng;Xiangdong, Lei;Yuanchang, Lu
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1479-1481
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    • 2003
  • The aim of this paper was mainly to interpret the real information-missing patch of image by using the kriging interpolation technology of spatial statistics. The TM Image of the Jingouling Forest Farm of Wangqing Forestry Bureau of Northeast China on 1 July 1997 was used as the tested material in this paper. Based on the classification for the TM image, the information pixel-missing patch of image was interpolated by the kriging interpolation technology of spatial statistics theory under the image treatment software-ERDAS and the geographic information system software-Arc/Info. The interpolation results were already passed precise examination. This paper would provide a method and means for interpreting the information-missing patch of image.

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Detection of Hotspots on Multivariate Spatial Data

  • Moon, Sung-Ho
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.4
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    • pp.1181-1190
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    • 2006
  • Statistical analyses for spatial data are important features for various types of fields. Spatial data are taken at specific locations or within specific regions and their relative positions are recorded. Lattice data are synoptic observation covering an entire spatial region, like cancer rates corresponding to each county in a state. Until now, the echelon analysis has been applied only to univariate spatial data. As a result, it is impossible to detect the hotspots on the multivariate spatial data In this paper, we expand the spatial data to time series structure. And then we analyze them on the time space and detect the hotspots. Echelon dendrogram has been made by piling up each multivariate spatial data to bring time spatial data. We perform the structural analysis of temporal spatial data.

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