• Communications for Statistical Applications and Methods
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• v.9 no.2
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• pp.505-514
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• 2002

Multiple correspondence analysis graphically shows the correspondent relationship among categories in multi-way contingency tables. It is well known that the proportions of the principal inertias as part of the total inertia is low in multiple correspondence analysis. Moreover, although this problem can be overcome by using the Benzecri formula, it is not enough to show clear correspondent relationship among categories (Greenacre and Blasius, 1994, Chapter 10). In addition, they show that Andrews' plot is useful in providing the correspondent relationship among categories. However, this method also does not give some concise interpretation among categories when the number of categories is large. Therefore, in this study, we will easily interpret the multiple correspondence analysis by applying the K-means clustering analysis.

• The Korean Journal of Applied Statistics
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• v.7 no.1
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• pp.69-74
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• 1994

Kim (1992) derived influence functions of rows and columns on the eigenvalues obtained in correspondence analysis (CA) of two-way contingency tables. As in principal component analysis, the eigenvalues are of great importance in CA. The goodness of a two dimensional correspondence plot is determined by the ratio of the sum of the two largest eigenvalues to the sum of all the eigenvalues. By investigating those rows and columns with high influence, a correspondence plot may be improved. In this paper, we extend the influence functions of CA to multiple correspondence analysis (MCA), which is a CA of multi-way contigency tables. An explicit formula of the influence function is given.

• The Korean Journal of Applied Statistics
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• v.15 no.1
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• pp.85-105
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• 2002

To explore the relationships among frequencies for sets of alleles, within or between loci, is one of the first analyses in population genetic study. The general question is whether the frequency of a set of alleles is the same as the product of each of the separate allele frequencies. For two alleles of a single locus, Hardy-Weinberg equilibrium is tested and for an allele from each of two loci, linkage disequilibrium is tested. However, it is more useful if we can quantify and graphically represent this information. In this study, we suggest graphical methods to find associations between alleles. We also analyze the STR data of Korean population as an illustration.

• Journal of the Korea Institute of Building Construction
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• v.20 no.3
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• pp.269-278
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• 2020

In this study, we analyzed the safety accidents that occurred in the apartment construction site and the correlations between the victims according to the type of work accidents through multiple correspondence analysis. There is a lack of disaster-related studies on apartment construction sites, the third most frequent building type in Korea, and most of them have used survey techniques. Therefore, the exploratory data analysis was conducted in industrial accident cause data, and derived the correlation analysis between each disaster victim through multiple correspondence analysis. The results of the study are summarized in two as follows. First, as the number of heights increased due to the high rise and complexity of apartments, the fall rate and mortality rate were high. In addition, deaths are mostly caused by very few experienced workers or those with more than 10 years of experience, resulting from safety training, lack of experience, and insensitivity to safety. Second, multi-correspondence analysis showed that most safety accidents can be prevented by wearing safety equipment, and following proper work process and its safety action. The key factors derived from this study can be used for safety education, supervision, and management in apartment construction sites.

• Journal of Environmental Policy
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• v.13 no.1
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• pp.25-47
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• 2014

We examined the heterogeneity in the financial -environmental performance nexus, carrying out a meta-analysis of 48 outcomes from 26 empirical studies. Multiple correspondence analysis (MCA) was performed in this study to facilitate the analysis of the structural relationship among an array of study characteristics. As expected, the results of analyzing the multiple studies of the general corporate environmental performance and financial performance link suggested a significant positive relationship. Some of the results of the moderator analysis suggest that empirical studies using self-reporting measurement and structural equation method benefited from environmental performance as much as or more than the archival and regression method.

• The Korean Journal of Applied Statistics
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• v.27 no.2
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• pp.169-183
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• 2014

Massive and various types of data recorded everywhere are called big data. Therefore, it is important to analyze big data and to nd valuable information. Besides, to standardize unstructured big data is important for the application of statistical methods. In this paper, we will show how to standardize unstructured big data using MapReduce which is a distribution processing system. We also apply simple correspondence analysis and multiple correspondence analysis to nd the relationship and characteristic of direct relationship words for Samsung Electronics and The Korea Economic Daily newspaper as well as Apple Inc.

• Industrial Engineering and Management Systems
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• v.13 no.1
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• pp.107-115
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• 2014

Offshore wind power has been extremely popular in recent years, and in the energy technology field, relevant research has been increasingly conducted. However, research regarding patent portfolios is still insufficient. The purpose of this research is to study the status of mainstream offshore wind power technology and patent portfolios and to investigate major assignees and countries to obtain a thorough understanding of the developmental trends of offshore wind power technology. The findings may be used by the government and industry for designing additional strategic development proposals. Data mining methods, such as multiple correspondence analyses and k-means clustering, were implemented to explore the competing technological and strategic-group relationships within the offshore wind power industry. The results indicate that the technological positions and patent portfolios of the countries and manufacturers are different. Additional technological development strategy recommendations were proposed for the offshore wind power industry.

• Quality Improvement in Health Care
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• v.12 no.2
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• pp.84-92
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• 2006

Background : To examine the difference between ICD-10 and The Korean standard classification of disease(oriental medicine), and to aim at improve the practical use as statistical data. It is one of the reason of disease classification. On that account we convert the many to many correspondence presenting classification of oriental medicine into many to one correspondence. Method : The study tracked out 155 patients discharged from the university hospital which is located in Gyeonggi Province and managing hospital and oriental medicine hospital from July to October this year. The period of this study was from August 1 to November 18. We compared correspondence between the two services' diagnosis(hospital services and oriental medicine hospital services) at the same time and attempted many to one correspondence classification. That is for production of statistical data. Result : We investigated the group which have had medical treatment experience of two kinds of services at the same time. The result of this investigation was that the same oriental medicine diagnosis used differently in western medicine diagnosis. 44.5% was accorded with western medicine diagnosis. Correspondence of the western medicine diagnose with the top of the Korean standard classification of disease(oriental medicine) list's western medicine diagnosis was 13.5%. For many to one correspondence classification for statistics, one western medicine diagnosis was selected for one oriental medicine diagnosis. In case of the main diagnosis(I sign) was not enough to explain oriental medicine diagnosis' characteristic, we chose multiple other diagnosis, so other diagnosis(II sign) about patient's cause of disease could be selected for supplement after we examined the patient's records. The statistics was possible with this many to one correspondence. Conclusion : The result of this study about correspondence between western medicine diagnoses and those of oriental medicine confirms that The Korean standard classification of disease(oriental medicine) is hard to be standardized with western medicine diagnosis. Therefore, according to this study, we use new many to one correspondence classification, multiple oriental medicine diagnoses with one ICD-10, which can be used by statistical data.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.6
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• pp.1431-1438
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• 1995

In this paper, we present a multiple-view stereo matching method in case of moving in the direction of optical axis with stereo camera. Also we analyze the obtainable depth precision to show that multiple-view stereo increases the virtual baseline with single-view stereo. This method decides candidate points for correspondence in each image pair and then search for the correct combinations of correspondences among them using the geometrical consistency they must satisfy. Adantages of this method are capability in increasing the accuracy in matching by using the multiple stereo images and less computation due to local processing. This method computes 3-D depth by averaging the depth obtained in each multiple-view stereo. We show that the resulting depth has more precision than depth obtainable by each independent stereo when the position of image feature is uncertain due to image noise. This paper first defines a multipleview stereo agorithm in case of moving in the direction of optical axis with stereo camera and analyze the obtainable precision of computed depth. Then we represent the effect of removing the incorrect matching candidate and precision enhancement with experimental result.

• Journal of Ecology and Environment
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• v.30 no.1
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• pp.39-47
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• 2007

The relationships between the cover of herbaceous species and 15 soil chemical properties (organic carbon contents, total N, available P, exchangeable K, Na, Ca and Mg, HCl-extractable Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in nine poorly controlled waste landfill sites in Korea were examined by correlation analysis and multiple regression equations. Species showed different patterns of correlation between their cover values and soil chemical properties. The cover of Ambrosia artemisiifolia var. elatior, Aster subulatus var. sandwicensis and Erechtites hieracifolia were negatively correlated with the contents of Fe, Mn and Ni within landfill soils. Total cover of all species in quadrats was positively correlated with the contents of Cd and negatively correlated with the contents of Mn and Fe from stepwise regression analysis with 15 soil properties. Canonical correspondence analysis demonstrated that the distribution of native and exotic plants on poorly controlled landfills was significantly influenced by the contents of Na and Ca in soils, respectively.