• Journal of the Korea Institute of Information Security & Cryptology
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• v.14 no.1
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• pp.15-23
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• 2004

Westfeld analyzed a sequential LSB embedding steganography effectively through the $\chi$$^2$statistical test which measures the frequencies of PoVs(pairs of values). Fridrich also proposed another statistical analysis, so-called RS steganalysis by which the embedding message rate can be estimated. This method is based on the partition of pixels as three groups; Regular, Singular, Unusable groups. In this paper, we propose a new steganographic scheme which preserves the above two statistics. The proposed scheme embeds the secret message in the innocent image by randomly adding one to real pixel value or subtracting one from it, then adjusts the statistical measures to equal those of the original image.

• Proceedings of the Safety Management and Science Conference
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• 2013.11a
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• pp.209-219
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• 2013

The research is to evaluate the statistical difference between K-GAAP(Generally Accepted Account Principles) in 2008 year and K-IFRS(International Financial Reporting Standards) in 2012 year. H Motor Company, S Electronics and L Electronics are the three representative firms adopting K-GAAP and K-IFRS in Korea. The ${\chi}^2$ homogeneous test are used to identify the reduction of the number of account items of four financial statements such as Statement of Financial Position(SFP), Statement of Comprehensive Income(SCI), Statement of Cash Flow(SCF), and Statement of Change in Equity(SCE) between K-GAAP and K-IFRS.

• Proceedings of the IEEK Conference
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• 2003.11b
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• pp.23-26
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• 2003

Westfeld[1] analyzed a sequential LSB embedding steganography effectively through the $\chi$$^2$-statistical test which measures the frequencies of PoVs(pairs of values). Fridrich also proposed another statistical analysis, so-called RS steganalysis by which the embedding message rate can be estimated. In this paper, we propose a new steganographic scheme which preserves the above two statistics. The proposed scheme embeds the secret message in the innocent image by randomly adding one to real pixel value or subtracting one from it, then adjusts the statistical measures to equal those of the original image.

• The Korean Journal of Applied Statistics
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• v.27 no.1
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• pp.115-122
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• 2014

A test for randomness of the binary random sequence is proposed in this paper. The proposed test statistic is based on the mean length of runs distributed with truncated geometric distribution and asymptotically ${\chi}^2_2$-distributed when the size of the sequences is large. A small Monte Carlo simulation compared the size of the test with a significant level as well as evaluated the test power. We applied the proposed method to the sequence of yes or no numbers in Lotto 6/45 and concluded that the randomness of Lotto is retained.

• Journal of muscle and joint health
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• v.12 no.2
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• pp.119-131
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• 2005

Purpose: The purpose of this study was to examine effect of Tai-Chi exercise program on pain, flexibility, perceived health status and instrumental activities of daily living for osteoarthritis patients. To evaluate the effects, quasi-experimental study was used for pre and post test with a nonequivalent control group. Method: Fifty-two subjects participated in the experiment(twenty-seven for experimental group and twenty-five for control group) and they were from two different senior citizen centers in J city. The experiment period was from April 2002 through August 2002. The experiment group took part in Tai-Chi exercise program for eighteen weeks(three times a week for four weeks and five times a week for fourteen week). The exercise was performed for 50 minutes at every time (15 minutes for warm-up, 30 minutes for Tai-Chi exercise, and 5 minutes for ending). In order to pursue study purpose, the SPSS/WIN 8.0 program was chosen for the statistical analysis; ANCOVA was employed in examining test hypothesis; t-test and $X^{2}-test$ were used to examine homogeneity between experimental and control group. Result: The study results were as follows: Score of pain decreased significantly after of Tai-Chi exercise program. Score of flexibility increased significantly after of Tai-Chi exercise program. Score of perceived health status increased significantly after of Tai-Chi exercise program. Score of IADL increased significantly after of Tai-Chi exercise program. Conclusion: As shown in the results, Tai-Chi exercise program can be effective nursing intervention for osteoarthritis patient to improve pain, flexibility, perceived health status and Instrumental Activities of Daily Living.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.19 no.3 s.31
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• pp.134-145
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• 2006

Objective : This study was carried out to investigate what type of assumption and conditions are needed for the application of various statistical techniques such as descriptive statistics, t-test, analysis of variance, correlation analysis, regression analysis and chi-square test and to evaluate that they are used correctly in the research process. Methods : One more methods of statistical analysis were used in 91 papers among 162 papers selected from the journal of Korean oriental medical Ophthalmology & Otolaryngology & Dermatology from April 2003 to December 2005. So we analysed the type of statistical analysis method in 91 papers(clinical and experimental study) and assessed the their validity of statistical techniques by the check list consisting of 34 items(3 items for validity assessment of descriptive statistics, 6 items for t-test, 7 items for analysis of variance, correlation analysis and regression analysis, respectively, 4 items for chi-square test) Results : 1. The type of 65(40%) cases is experimental trial, the type of 55(34%) cases is case report, the type of 26(16%) cases is clinical trial and the type of 16(10%) cases is review, in 91 papers using statistical techniques among 162 papers selected from the journal of Korean oriental medical Ophthalmology & Otolaryngology & Dermatol-ogy from April 2003 to December 2005. 2. One more methods of statistical analysis were used in the experimental and clinical study. When we classified 125 units using statistical analysis methods in 91 papers according to statistical techniques such as descriptive statistics, t-test, analysis of variance, correlation analysis, regression analysis and chi-square test, the number of independent sample t-test is 33(26%), the number of only descriptive statistics is 28(22%), the number of independent sample t-test is 33(26%), the number of only descriptive statistics is 28(22%), the number of one way ANOVA is 15(12%), the number of non-parametric test 10(8%). 3. After carrying out one way ANOVA, the number of using multiple comparison methods is 15(Scheffe:6(26%), Duncan:4(17%), Dunnett:3(13%), Tukey:2(9%)) out of 23 (total case carrying out one way ANOVA). 8(35%) out of 23 did not enforce multiple comparison methods after carrying out one way ANOVA. 4. From the assessment of validity about 63 cases using statistical techniques(except descriptive statistics), 5(8%) cases are proper, the other 58(92%) are improper, so we recognized a serious misuse of statistical application in our journal. 5. The number of case below 10 sample size in experimental and clinical study(except descriptive statistics) is 31(34%) and frequent. Also the number of case containing no mention of sample size is 41(45%, including culture study). 6. For example of statistical error, there are wrong choice of statistical technique, lack of check on standard assumption(such as standard distribution, equivariance, independence), and so on. Conclusions : We investigated the validity of statistical analysis methods in our journal by check list consisting of 34 items and suggested correct statistical analysis methods. We should practice the spread of education about statistical analysis methods and precis application, enhance objectivity and reliability of our thesis and further correspond with purpose of scientific study.

• The Korean Journal of Applied Statistics
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• v.17 no.1
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• pp.89-103
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• 2004

If the given information is exact, though it is the little, we had better use it than not use in analysis. In this article, the problem of independence test in a contingency table is considered when two marginal distributions of a population are given exactly. For that case, a likelihood-ratio chi-squared test statistic and its Pearsonian type chi-squared test statistic are derived. By Monte Carlo Simulations the traditional chi-square tests and the derived tests are compared. And the related some testing problems are synthetically explained on a geometrical viewpoint.

• The Korean Journal of Applied Statistics
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• v.10 no.2
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• pp.339-352
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• 1997

Chi-square test based on large sample theory is inappropriate for testing the row homogeneity in two-way contingency table with several sparse cells. For that case, exact testing methods has been developed in the literature and implemented in StatXact(1991). However, considerable computing time is inevitable for moderate size tables. So, Monte Carlo approximation is recommended frequently. In this study, we propose a simple algorithm for generating two-way random tables with fixed row and column margins for small sample chi-square test. Also, we develop “Turkey-type” method for multiple between-row comparisons.

• Korean Journal of Oriental Medicine
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• v.13 no.2 s.20
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• pp.121-125
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• 2007

Background and Purpose : The purpose of this study was done to investigate what kinds of statistical techniques have been used to analyze data from oriental medicine research Methods : 135 original articles which used statistical techniques in their data analysis were selected from the articles published in The Journal of Korea Institute of Oriental Medicine(JKIOM) between 1995 to 2007. Results : Among 135 articles, 59 articles used descriptive statistics while 76 articles used inferential statistics for data analysis. For that 76 articles, two-sample t-test(33 articles), analysis of variance(29 articles), regression(9 articles), chi-square test(5 articles), nonparametic test(4 articles), Fisher's exact test(3 articles), and other test(9 articles) were chosen to analyze the data. SAS and SPSS statistical softwares(82.50%) were mostly used to analyze the data. Nonparametic tests were used to 4 articles(6.97%) of 67 articles and parametic tests were used to 63 articles(93.03%) of 67 articles. Among 29 articles used analysis of variance, duncan(8 articles), dunnet(4 articles), bonferroni(4 articles), turkey(3 articles), scheff(1 article) were used to do multiple comparison. 9 articles did not carry out the multiple comparison. Conclusions : It was found that the frequencies of statistical package used and statistical analysis used were not much by now. High level statistical analyses were not used most for oriental medicine research.

• Journal of the Korean Statistical Society
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• v.27 no.2
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• pp.205-220
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• 1998

Dependence concepts for ordered two-way contingency tables have been of considerable interest. We consider a dependence concept which is less restrictive than likelihood ratio dependence and more restrictive than regression dependence. Maximum likelihood estimation of cell probability under this dependence restriction is studied. The likelihood ratio statistics for and against this dependence are proposed and their large sample distributions are derived. A real data is analyzed to illustrate the estimation and testing procedures.