• Title/Summary/Keyword: Chi square test

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Locating and Searching Hidden Messages in Stego-Images (스테고 이미지에서 은닉메시지 감지기법)

  • Ji, Seon-Su
    • Journal of Korea Society of Industrial Information Systems
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    • v.14 no.3
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    • pp.37-43
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    • 2009
  • Steganography conceals the fact that hidden message is being sent on the internet. Steganalysis can be detected the abrupt changes in the statistics of a stego-data. After message embedding, I have analyzed for the statistical significance of the fact the occurrence of differences among the four-neighboring pixels. In this case, when a embedding messages within a images is small, use EC value and chi-square test to determine whether a distribution in an images matches a distribution that shows distortion from stego-data.

Numerical Approach with Kolmogorov-Smirnov Test for Detection of Impulsive Noise (임펄스성 잡음의 유무를 결정하는 Kolmogorov-Smirnov 검증의 수치적 접근의 효율성)

  • Oh, Hyungkook;Nam, Haewoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.9
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    • pp.852-860
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    • 2014
  • This paper proposes an efficient algorithm based on Kolmogorov-Smirnov test to determine the presence of impulsive noise in the given environment. Kolmogorov-Smirnov and Chi-Square tests are known in the literature to serve as a goodness-of-fit test especially for a testing for normality of the distribution. But these algorithms are difficult to implement in practice due to high complexity. The proposed algorithm gives a significant reduction of the computational complexity while decreasing the error probability of hypothesis test, which is shown in the simulation results. Also, it is worth noting that the proposed algorithm is not dependent on the noise environment.

A Comparative Study on the Infinite NHPP Software Reliability Model Following Chi-Square Distribution with Lifetime Distribution Dependent on Degrees of Freedom (수명분포가 자유도에 의존한 카이제곱분포를 따르는 무한고장 NHPP 소프트웨어 신뢰성 모형에 관한 비교연구)

  • Kim, Hee-Cheul;Kim, Jae-Wook
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.10 no.5
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    • pp.372-379
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    • 2017
  • Software reliability factor during the software development process is elementary. Case of the infinite failure NHPP for identifying software failure, the occurrence rates per fault (hazard function) have the characteristic point that is constant, increases and decreases. In this paper, we propose a reliability model using the chi - square distribution which depends on the degree of freedom that represents the application efficiency of software reliability. Algorithm to estimate the parameters used to the maximum likelihood estimator and bisection method, a model selection based on the mean square error (MSE) and coefficient of determination($R^2$), for the sake of the efficient model, were employed. For the reliability model using the proposed degree of freedom of the chi - square distribution, the failure analysis using the actual failure interval data was applied. Fault data analysis is compared with the intensity function using the degree of freedom of the chi - square distribution. For the insurance about the reliability of a data, the Laplace trend test was employed. In this study, the chi-square distribution model depends on the degree of freedom, is also efficient about reliability because have the coefficient of determination is 90% or more, in the ground of the basic model, can used as a applied model. From this paper, the software development designer must be applied life distribution by the applied basic knowledge of the software to confirm failure modes which may be applied.

Chi-Squared Test of Independence in Case that Two Marginal Distributions are Given Exactly (모집단 부분정보가 주어진 상황에서의 분할표 독립성 검정)

  • 이광진
    • 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 exponential generalized log-logistic model: Bagdonavičius-Nikulin test for validation and non-Bayesian estimation methods

  • Ibrahim, Mohamed;Aidi, Khaoula;Alid, Mir Masoom;Yousof, Haitham M.
    • Communications for Statistical Applications and Methods
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    • v.29 no.1
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    • pp.1-25
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    • 2022
  • A modified Bagdonavičius-Nikulin chi-square goodness-of-fit is defined and studied. The lymphoma data is analyzed using the modified goodness-of-fit test statistic. Different non-Bayesian estimation methods under complete samples schemes are considered, discussed and compared such as the maximum likelihood least square estimation method, the Cramer-von Mises estimation method, the weighted least square estimation method, the left tail-Anderson Darling estimation method and the right tail Anderson Darling estimation method. Numerical simulation studies are performed for comparing these estimation methods. The potentiality of the new model is illustrated using three real data sets and compared with many other well-known generalizations.

The Relationship of Alcohol Use Disorders and Depression, Qualty of Life in the Eldery (노인의 알코올 사용장애에 따른 우울, 삶의 질과의 관계)

  • Oh, Chung-Uk;Kim, Seon-Rye
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.1
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    • pp.196-201
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    • 2014
  • This study intends to investigate alcohol use disorder in the elderly in rural area. The subjects were 212 elderly people. Alcohol use disorder was defined as a score of more than 10 points on the AUDIT-K. The collected data were analyzed descriptive statistics, chi-square test and t-test using SPSS 19.0 program. The alcohol use disorder in the elderly in rural area were 18.4%. The alcohol use disorder was statistically significant difference according to gender, age, inmate, scholarship, religion, job and smoking. The alcohol use disorder correlated positively with depression. To prepare the aging society, the government should make preparation prorgram for elderly alcoholics.

Analysis of Young Adult Information Concentrating on the Significance of Application of Cartoon Characters on Garments (캐릭터를 의류상품에 응용하기 위한 신세대 소비자 정보 분석)

  • 김칠순;조예진
    • Journal of the Korean Society of Costume
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    • v.51 no.4
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    • pp.31-42
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    • 2001
  • The purpose of this study was to develop a large representative data base for character goods marketing strategy. The study was to determine character name awareness in relation to segmented distribution regions and such demographic variables as sex and age. The author also analyzed preferred design. A total of 360 questionnaires were distributed and 359 reliable ones were used for statistical analysis. A SAS statistical package including frequency tables and Chi square test and factor analysis and Kendall′s relation analyses was used. The results are as follow : character name awareness involves "character name decognition" based on asking subjects to identify character names from 50 given names. "Tele-tubbies" was found to be a dominant commercial character name as a result of the recognition test, and "Sailer-moon" was found to be a dominant animation character goods as a result of the recognition test. Character recognition was significantly different in the segmented distribution legions, three age groups and different sex groups. People considered design first in purchasing any character goods, and they considered color second in purchasing them. The most favored part of garment far character to be stitch to was the center front in the T-shirt/dress shirt, the center back in the Jumper/jacket, back pocket in the trousers/skirt. The results of a Chi-square test showed that preferred part in the trousers/skirt of character was related with age variables.

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The Association between Seven Health Practices and Self Rated Health by Sasang Constitution (사상체질별 7대 건강행위와 주관적 건강상태의 연관성)

  • Jang, Eun-Su;Kim, Yun-Young;Baek, Young-Hwa;Lee, Si-Woo
    • Journal of Sasang Constitutional Medicine
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    • v.30 no.1
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    • pp.32-42
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    • 2018
  • The purpose of this study aimed to know the association between seven health practices and self rated health by Sasang constitution. We recruited 367 subjects aged from 30 to 59. KS 15 questionnaire was used to classify Sasang constitution and visual analogue scale was used to estimate self rated health. Chi-square test was used to know the difference of occupation distribution by Sasang constitution. Anova test, T-test and Chi-square test also used to analyze the difference of self rated health between the health practice group and non-health group in individual Sasang constitution. SPSS 21.0K was used and significant p was <.05. Regular morning meal, non-snaking, good sleeping and sufficient exercise had higher self rated health score (p<.05). Regular morning meal, good sleeping and sufficient exercise had higher score in Tae-eumin (p<.05). Good sleeping had higher self rated health score in Soeumin and Soyangin (p<.05). These results suggest there is possibility that health practices for health promotion could be different according to Sasang constitution.

Analysis of Korean Consumer Brand Awareness and Preferred Types of Sock Design (국내 양말 소비자의 브랜드 인지도 및 디자인 선호도 분석)

  • Kim, Chil-Soon;Nam, Young-Mi;Kim, Hyun-Su
    • Fashion & Textile Research Journal
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    • v.1 no.4
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    • pp.335-341
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    • 1999
  • The purpose of this study was to develop a large representative data base for socks marketing strategy. The study was to determine socks brand awareness in ralation to segmented distribution regions and such demographic variables as sex and age. The authors also analyzed preferred design. A total of 650 questionnaires were distributed and 611 reliable ones were used for statistical analysis. A SAS statistical package including frequency tables and chi square test was used. The results are as follows: Brand awareness involves "brand recall" based on asking a person to name the brand he or she recalls first, and also "brand recognition" based on asking subjects to identify brand names from 30 given brands. 'SOCKSTOP' was found to be a dominant brand as a result of the brand recall test, and 'BYC' was found to be a dominant brand as a result of the brand recognition test. Brand recognition was significantly different in the segmented distribution regions, three age groups and different sex groups. People considered design first in purchasing sports/casual socks, while they considered color first in purchasing dress socks. The most favored type of sock style was the common crew sock type. The results of a chi square test showed that preferred type of sock design was related with the sex and age variables.

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Analysis on Reports of Statistical Testings for Mean Differences (차이검정을 이용한 논문의 통계활용 분석)

  • Chung, Chae-Weon;Kim, Jeung-Im;Park, Hye-Sook;Ahn, Suk-Hee;Cho, Dong-Sook;Park, So-Mi
    • Women's Health Nursing
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    • v.13 no.3
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    • pp.211-218
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    • 2007
  • Purpose: This study aimed to evaluate the accuracy and adequacy of research papers reporting statistical testings for mean differences. Methods: Original research articles utilized t-test, Chi-square test, and ANOVA were reviewed from Korean Journal of Women Health Nursing published from the year 2004 to 2006. Seventy-six papers were evaluated in accordance with formatted criteria in respect to an inclusiveness of research title, accuracy of statistical methods and presentation styles, and errors in reporting statistical outcomes. Results: Research titles were quite comprehensive, however overall accuracy of statistical values and basic formats reached only 60 to 80% by items. Details of the presentation in the reporting of outcomes were not complied with the guidelines, which need careful concerns of the writers. Errors of English in table presentation were found in more than 30% of the papers. Conclusion: The outcome would be reflected in the submission guidelines for future writers. To reach the level comparable with internationally recognized nursing journals, concrete knowledge to apply statistical methods should be ensured in the processes of submission, reviews, and editing.

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