• Title/Summary/Keyword: moran's I

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Aanalysis the Structure of Heat Environment in Daegu Using Landsat-8 (Landsat-8을 활용한 대구시 열 환경구조 분석)

  • Kim, Jun Hyun;Choi, Jin Ho
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.4_1
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    • pp.327-333
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    • 2014
  • To improve thermal environments in urban area, the structural characteristic analysis of thermal environments of the certain area should be preceded to analyze and supplement its problems. With Landsat-8, we measured the centrality estimation, the distribution map, and the spatial statistical analysis of Daegu Metropolitan City in January and August, which of data applied in analyzing the structure of thermal environments following to its spatial property. The thermal infrared band of satellite images has been used to analyze the standard normal deviated scores, which extract the centrality, while the cluster map, based upon Local Local Moran's I, has composed for understanding the autocorrelation of local spatial within environment space structure. Understanding the distribution features as well as the pivot center of thermal environments with satellite images provides principle database for updating urban thermal environments' policies and plans; because those are reference materials that should have precedence over for diverse thermal environment policies.

Spatial Distribution Patterns and Population Structure of Doellingeria scabra at Mt. Maebong in Korea (한국 매봉산 참취의 공간적 분포 양상과 집단 구조)

  • Lee, Byeong Ryong;Huh, Man Kyu
    • Journal of Life Science
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    • v.29 no.7
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    • pp.762-768
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    • 2019
  • Doellingeria scabra Thunb. (syn. Aster scaber Thunb.), a perennial herb in the family Asteraceae, is frequently found in the wild mountain regions of Korea. This aim of this work was to measure the characteristics of patchiness of D. scabra in a local population on Mt. Maebong in Taeback-ci, Gangwon-do. The spatial distribution pattern of this species was estimated by analyzing ecological data by methods including the index of dispersion, Lloyd's mean crowding, and Morisita's index. The mean population density of the D. scabra population was 2.94. The D. scabra individuals were uniformly or randomly distributed in small-scale plots and were aggregately distributed in two large-scale plots ($16{\times}32m^2$ and $32{\times}32m^2$). The mean crowding ($M^*$) was 0.916. The mean patchiness index (PAI) was 0.796. Morisita's coefficient tended to decrease the density of the population as the plot size increased. The expected value of Eberhardt's index ($I_E$) in the local population was 2.623. Moran's I of D. scabra significantly differed from the expected value in 6 of 8 cases (75.0%). The first five classes were positive, with four showing statistical significance, indicating similarity among individuals in the first four distance classes (I-IV, 8 m), The results presented here could provide a theoretical basis for the conservation of D. scabra (Korean: chamchwi) and for the rehabilitation and sustainable management of forest ecosystems on Mt. Maebong, as well as on other mountains.

Analysis of Eunpyeong New Town Land Price Using Geographically Weighted Regression (지리가중회귀분석을 이용한 은평뉴타운 지가 분석)

  • Jung, Hyo-jin;Lee, Jiyeong
    • Spatial Information Research
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    • v.23 no.5
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    • pp.65-73
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    • 2015
  • Newtown Business of Seoul had been performed to reduce deterioration of Gangbuk and economic inequality between Gangnam and Gangbuk. According to this, Eunpyeong-gu was set as test-bed for Newtown business and Newtown business had been completed until 2013. This study aims to analyze the influence of social and economical factors which affect land price using GWR (Geographically Weighted Regression) considered spatial effect. As a result of analysis, GWR model demonstrated a better goodness-of-fit than OLS (Ordinary least square) model typically used in most study. Furthermore, AIC value and Moran's I of residual prove that GWR model is more suitable than OLS model. GWR model enable to explain more detailed than global regression model as coefficient and sign show different value locally. In future, this research will be helpful to develop Eunpyeong-gu considering spatial characters and strength effectiveness of development.

Correlation and Spatial Analysis between the number of Confirmed Cases of the COVID-19 and Traffic Volume based on Taxi Movement Data (택시 이동 데이터 기반 COVID-19 확진자 수와 교통량 간의 상관관계 및 공간분석)

  • Jeon, Seung Bae;Kim, Geon;Jeong, Myeong-hun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.39 no.6
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    • pp.609-618
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    • 2021
  • The spread and damage of COVID-19 are putting significant pressure on the world, including Korea. Most countries place restrictions on movement and gathering to minimize contact between citizens and these policies have brought new changes to social patterns. This study generated traffic volume data on the scale of a road network using taxi movement data collected in the early stages of the COVID-19 third pandemic to analyze the impact of COVID-19 on movement patterns. After that, correlation analysis was performed with the data of confirmed cases in Daegu Metropolitan City and Local Moran's I was applied to analyze the effect of spatial characteristics. As a result, in terms of the overall road network, the number of confirmed cases showed a negative correlation with taxi driving and at least -0.615. It was confirmed that citizens' movement anxiety was reflected as the number of confirmed cases increased. The commercial and industrial areas in the center of the city confirmed the cold spot with a negative correlation and low-low local Mona's I. However, the road network around medical institutions such as hospitals and spaces with spatial characteristics such as residential complexes was high-high. In the future, this analysis could be used for preventive measures for policymakers due to COVID-19.

Spatial Price Competition in the Korean Retail Gasoline Market

  • Kim, Donghun;Lee, Jiyon
    • Environmental and Resource Economics Review
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    • v.23 no.4
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    • pp.553-581
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    • 2014
  • This paper analyzes competition among service stations in the Korean gasoline market. We consider spatial differentiation as a source of product differentiation as well as the characteristics of the stations and vertical contracts between refiners and retailers as factors causing changes in equilibrium prices in the Korean gasoline retail market. The effect of the government's price disclosure policy on the retail market competition is also analyzed. Moran's I test indicates that the prices of neighboring gas stations are spatially correlated in the market. It is also found that gasoline prices for vertically integrated stations are much lower than those for independent stations. In addition, unbranded stations charge lower prices than branded stations but also induce branded stations to price more competitively. Meanwhile, the government's price disclosure policy did intensify price competition in the retail gasoline market. It is inferred that the price disclosure policy contributed to retailers gaining more bargain power in price negotiation with refiners, causing an eventual increase in retail prices.

Phytosociological Study and Spatial autocorrelation on the Forest Vegetation of Mt. Yeonae at Gijang-gun

  • Choi, Byoung-Ki;Huh, Man Kyu
    • Journal of Environmental Science International
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    • v.22 no.11
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    • pp.1373-1381
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    • 2013
  • Mt. Yeonae is at Gijang-gun in Busan and is surrounded by farming lands on three sides. The search for the species composition and dynamics of local communities were studied at Mt. Yeonae of how spatial similarity decays with geographic distance. The index values of Z$\ddot{u}$rich-Montpellier School's phytosociology at the 12 plots was compared to a distribution of similarly using 20 m quadrates at 12 sites. The specific communities were five including Pinus densiflora - Quercus variabilis community. Six species were significant similarity between neighboring sites by using the spatial autocorrelation coefficient, Moran's I. If Mt. Yeonae was destroyed by an artificial action, some spatial correlated species such as P. densiflora and Q. variabilis will be collapsed because of no maintaining the effective population sizes.

A Study on the Selection of Variogram Using Spatial Correlation

  • Shin, Key-Il;Back, Ki-Jung;Park, Jin-Mo
    • Communications for Statistical Applications and Methods
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    • v.10 no.3
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    • pp.835-844
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    • 2003
  • A difficulty in spatial data analysis is to choose a suitable theoretical variogram. Generally mean squares error(MSE) is used as a criterion of selection. However researchers encounter the case that the values of MSE are almost the same whereas the estimates of parameters are different. In this case, the selection criterion based on MSE should take into account the parameter estimates. In this paper we study on the method of selecting a variogram using spatial correlation.

Online Information Retrieval and Changes in the Restaurant Location: The Case Study of Seoul (온라인 정보검색과 음식점 입지에 나타나는 변화: 서울시를 사례로)

  • Lee, Keumsook;Park, Sohyun;Shin, Hyeyoung
    • Journal of the Economic Geographical Society of Korea
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    • v.23 no.1
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    • pp.56-70
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    • 2020
  • This study identifies the impact of social network service (SNS) on the spatial characteristics of retail stores locations in the hyper-connected society, which have been closely related to the everyday lives of urban residents. In particular, we focus on the changes in the spatial distribution of restaurants since the information retrieval process was added to the decision-making process of a consumer's restaurant selection. Empirically, we analyze restaurants in Seoul, Korea since the smart-phone was introduced. By applying the kernel density estimation and Moran's I index, we examine the changes in the spatial distribution pattern of restaurants during the last ten years for running, newly-open and closed restaurants as well as SNS popular ones. Finally, we develop a spatial regression model to identify geographic features affecting their locations. As the results, we identified geographical variables and online factors that influence the location of restaurants. The results of this study could provide important groundwork for food and beverage location planning and policy formulation.

A Quantitative Analysis of the Spatial Agglomeration Pattern among the Korean Cities (한국 도시들의 공간집적 패턴에 대한 계량분석)

  • Sohn, Jungyul
    • Journal of the Korean Geographical Society
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    • v.48 no.1
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    • pp.56-71
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    • 2013
  • The purpose of this study is to examine the spatial distributional characteristics of industries among the Korean cities and to conduct industry classification using the findings. For this purpose, 82 cities in Korea are investigated with respect to 15 industrial sectors. In the analysis, concentration of and association between industries are recognized using both geographic and non-geographic measures. In order to measure concentration and association, locational Gini coefficient, Moran's I, correlation coefficient, and bivatiate Moran are used and 15 industrial sectors are classified based on these estimates. The findings reveal that the chemical sector shows strong geographic and non-geographic concentrations while the assembly, machinery and electronics sector only shows a strong geographic concentration. Printing and publishing, wholesale, and business services show a strong non-geographic association with other sectors. The remaining ten sectors show no explicit distribution patterns among cities. This study contributes to providing the methodology that analyzes the spatial distribution patterns of industries in a comprehensive way and is able to provide useful information in implementing industrial location policies including industrial clusters.

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Spatial Autocorrelation within a Korean Population of Alnus hirsuta (한국내 물오리나무(Ainus hirsuta) 집단의 공간적 상관관계)

  • Park, Joo-Soo
    • Journal of Life Science
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    • v.14 no.2
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    • pp.345-350
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    • 2004
  • The present study was investigated microgeographic variations to spatial autocorrelation in the Korean alder, Alnus hirsuta. Separate counts of each type of join (combination of genotypes at a single locus) for each allele, and for each distance class of separation, were tested for significant deviation from random expectations by calculating the Standard Normal Deviation (SND). Moran's I was significantly different from the expected value in 24 of 120 cases (20.0%). 17 of these values (14.2%) were significantly negative, indicating genetic dissimilarity among pairs of individuals in the ten distance classes. Many Korean populations of alder are small and are distributed by men for firewood. This occasional cutting of seed-bearing stems may bring a high level of gene flow. In addition, stump sprouting ability also may contribute to the fact that the Chengkwang population at Gijang is unusual in lacking spatial genetic structure.