• Journal of Information Processing Systems
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• 제4권1호
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• pp.27-32
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• 2008

Minimum support and confidence have been used as criteria for generating association rules in all association rule mining algorithms. These criteria have their natural appeals, such as simplicity; few researchers have suspected the quality of generated rules. In this paper, we examine the rules from a more rigorous point of view by conducting statistical tests. Specifically, we use contingency tables and chi-square test to analyze the data. Experimental results show that one third of the association rules derived based on the support and confidence criteria are not significant, that is, the antecedent and consequent of the rules are not correlated. It indicates that minimum support and minimum confidence do not provide adequate discovery of meaningful associations. The chi-square test can be considered as an enhancement or an alternative solution.

• 대한한의학방제학회지
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• 제20권1호
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• pp.133-147
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• 2012

Objectives : This study was intended to understand characteristics of symptoms, oriental medicine prescription and laboratory test results according to elapsed time of stroke. Methods : Through the medical records of 205 stroke inpatients in the oriental medical hospital in the year 2010, we investigated manifested symptoms, administered oriental medicine prescription and clinical pathological examination results. Collected items were classified to depend on stroke types, cerebral infarction and hemorrhage. We analyzed association between manifested symptoms, the oriental medicine prescription, and laboratory test results of stroke patients and elapsed time. Chi-square tests were performed to determine the significance level of association. Results : All symptoms, prescriptions and laboratory test results in cerebral infarction patients were associated with elapsed time. Especially, symptoms, prescriptions and pathological examination results showed very high statistical significance with elapsed time (a symptom; chi-square(df)=164.3(22), p<0.001, prescription; chi-square(df)=93.5(22), p<0.001, and pathological examination results; chi-square(df)=164.3(22), p<0.0004). But in the case of cerebral hemorrhage, there was not statistical significance. Conclusions : The elapsed time of stroke may be an essential requisite in catching symptoms and prescribing for stroke patients in oriental medical treatment.

• Journal of Information Technology Applications and Management
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• 제27권3호
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• pp.19-36
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• 2020

The Internet of things (IoT) is a system of interrelated computed devices, digital machines and any physical objects which are provided with unique identifiers and the potential to transmit data to people or machine (M2M) without requiring human interaction. IoT devices can be used to monitor and control the electrical and electronic systems used in different fields like smart home, smart city, smart healthcare and etc. In this study we introduce four imaginary IoT devices as a learning support assistants according to students' dominant learning styles measured by Honey and Mumford Learning Styles: Activists, Reflectors, Theorists and Pragmatists. This research emphasizes the association between students' strong learning styles and a preference to appropriate IoT devices with specific characteristics. Moreover, different levels of IoT devices' architecture are clearly explained in this study where all the artificial devices are designed based on this structure. Data analysis of experiment were measured by the use of chi square test for association and research results showed the statistical significance of the estimated model and the impacts of each category over the model where we finally got accurate estimates for our research variables. This study revealed the importance of considering the students' dominant learning styles before inventing a new IoT device.

• Genomics & Informatics
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• 제5권4호
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• pp.168-173
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• 2007

In previous nuclear genomic association studies, Random Forests (RF), one of several up-to-date machine learning methods, has been used successfully to generate evidence of association of genetic polymorphisms with diseases or other phenotypes. Compared with traditional statistical analytic methods, such as chi-square tests or logistic regression models, the RF method has advantages in handling large numbers of predictor variables and examining gene-gene interactions without a specific model. Here, we applied the RF method to find the association between mitochondrial single nucleotide polymorphisms (mtSNPs) and diabetes risk. The results from a chi-square test validated the usage of RF for association studies using mtDNA. Indexes of important variables such as the Gini index and mean decrease in accuracy index performed well compared with chi-square tests in favor of finding mtSNPs associated with a real disease example, type 2 diabetes.

• Journal of the Korean Data and Information Science Society
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• 제17권2호
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• pp.543-557
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• 2006

This paper is concerned with the applicability of the chi-square approximation to the six disparity statistics: the Pearson chi-square, the generalized likelihood ratio, the power divergence, the blended weight chi-square, the blended weight Hellinger distance, and the negative exponential disparity statistic. Three dimensional contingency tables of small and moderate sample sizes are generated to be fitted to all possible hierarchical log-linear models: the completely independent model, the conditionally independent model, the partial association models, and the model with one variable independent of the other two. For models with direct solutions of expected cell counts, point estimates and confidence intervals of the 90 and 95 percentage points of six statistics are explored. For model without direct solutions, the empirical significant levels and the empirical powers of six statistics to test the significance of the three factor interaction are computed and compared.

• 한국수자원학회논문집
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• 제46권6호
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• pp.667-681
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• 2013

본 연구에서는 삽교천유역에 위치한 19개 수질관측지점의 16년간(1995~2010) 월별 용존산소(dissolved oxygen: DO)자료를 이용하여 월별 및 계절별 용존산소 추세를 분석하였다. 추세분석을 위해 Mann-Kendall 추세분석과 Sen's slope 방법을 적용하였다. 또한 삽교천 유역을 4개 구역(삽교호, 삽교천본류, 무한천 및 곡교천)으로 구분하여 카이스퀘어 동질성 검정(chi-square homogeneity test)을 실시하여 각 구역의 월별, 그리고 계절별 용존산소추세의 동질성 유무를 분석하였다. 분석결과 대부분 수질관측지점의 월별, 계절별 용존산소는 증가추세를 보이거나 혹은 유의한 추세를 보이지 않았다. 또한 삽교천 유역 수질관측지점들의 계절별 용존산소추세는 서로 동질성을 보인 반면에 월별 용존산소추세는 수질관측지점이 저수지에 위치한 지점의 경우 동질성을 보이지 않았다. 전반적으로 삽교천 유역 수질관측지점의 용존산소 추세는 각 수질관측지점의 위치와 계절에 따라서 다른 양상을 보였다.

• 복식문화연구
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• 제7권4호
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• pp.155-167
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• 1999

The present study investigated various sales training programs used by apparel companies and compared each other in order to provide an important information for developing effective training programs for professional salesperson. Sixty eight companies were used and grouped into four categories based on brand characteristics : domestic national brand(DNB), casual brand(CB), foreign brand(FB) and domestic designer brand(DDB). Data were collected from the managers in charge or training salesperson by both questionnaires and personal and telephone interviews. Data were collected during July in 1998, and analyzed by using ANOVA, Duncan\`s multiple range test, and Chi-square test. Since the sample size was small, Yates\` correction formula was used to maximize statistical validity in non-parametric procedure of Chi-square test. The main purpose of sales training indicated by the companies were to satisfy customers and to maximize the profit. Significant differences were found among the groups in the importance level of training contents such as knowledge, and customer relation, training methods, place, and duration/frequency of training at training center.

• 물과 미래
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• 제22권4호
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• pp.441-451
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• 1989

한반도 주변해상에 큰 영향을 미친 태풍 LEE, VERA, THELMA 통과시의 파랑관측 자료에 대하여 zero-up & down crossing법 및 Tucker-Draper법으로 구한 유의파고를 파랑스펙트럼법으로 구한 유의파고와 비교분석하였다. 그리고 zero-up crossing법으로 구한 개별파의 파고분포를 Rayleigh, Weibull, Gluhovski, Ibrageemov, Goda의 분포와 비교한 후 Chi-square 검증을 실시하였다. 분석결과 zero-crossing법으로 구한 유의파고가 스펙트럼에서 구한 유의파고와 가장 잘 일치하였으며, 파고분포는 Rayleigh와 Goda 분포가 관측치에 가장 잘 맞는 것으로 나타났다.

• 사상체질의학회지
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• 제30권1호
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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.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1093-1096
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• 2012

Background: Cervical cancer is common among women worldwide. A multitude of risk factors aggravate the disease. This study was conducted to: (1) determine the prevalence and (2) make a comparative analysis of the socio-demographic and behavioural risk factors of cervical cancer and knowledge, attitude and practice between rural and urban women of North Bengal, India. Study Design: Community-based cross-sectional study. Methods: A survey (first in North Bengal) was conducted among 133 women in a rural area (Kawakhali) and 88 women in an urban slum (Shaktigarh) using predesigned semi-structured questionnaires. The respondents were informed of the causes (including HPV), signs and symptoms, prevention of cervical cancer and treatment, and the procedure of the PAP test and HPV vaccination. Results: The prevalence of risk factors like multiparity, early age of marriage, use of cloth during menstruation, use of condom and OCP, early age of first intercourse was 37.2%, 82%, 83.3%, 5.4%, 15.8% and 65.6% respectively. Awareness about the cause, signs and symptoms, prevention of cervical cancer, PAP test and HPV vaccination was 3.6%, 6.3%, 3.6%, 9.5% and 14.5% respectively. Chi-square testing revealed that in the study population, significant differential at 5% exists between rural and urban residents with respect to number of children, use of cloth/sanitary napkins, family history of cancer and awareness regarding causes of cervical cancer. Regarding KAP, again using chi-square tests, surprisingly, level of education is found to be significant for each element of KAP in urban areas in contrast to complete absence of association between education and elements of KAP in rural areas. Conclusions: A large number of risk factors were present in both areas, the prevalence being higher in the rural areas. The level of awareness and role of education appears to be insignificant determinants in rural compared to urban areas. This pilot study needs to be followed up by large scale programmes to re-orient awareness campaigns, especially in rural areas.