• Title/Summary/Keyword: Statistical Difference

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A Comparison of the Interval Estimations for the Difference in Paired Areas under the ROC Curves (대응표본에서 AUC차이에 대한 신뢰구간 추정에 관한 고찰)

  • Kim, Hee-Young
    • Communications for Statistical Applications and Methods
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    • v.17 no.2
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    • pp.275-292
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    • 2010
  • Receiver operating characteristic(ROC) curves can be used to assess the accuracy of tests measured on ordinal or continuous scales. The most commonly used measure for the overall diagnostic accuracy of diagnostic tests is the area under the ROC curve(AUC). When two ROC curves are constructed based on two tests performed on the same individuals, statistical analysis on differences between AUCs must take into account the correlated nature of the data. This article focuses on confidence interval estimation of the difference between paired AUCs. We compare nonparametric, maximum likelihood, bootstrap and generalized pivotal quantity methods, and conduct a monte carlo simulation to investigate the probability coverage and expected length of the four methods.

Analysis of Refractive Status between Urban and Rural Region in 13-year-old Children (도시와 농촌의 13세 어린이에 대한 굴절상태 분석)

  • Kim, Douk-Hoon;Kim, Jung-Sook
    • Journal of Korean Clinical Health Science
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    • v.5 no.1
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    • pp.808-815
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    • 2017
  • Purpose. To analyze the refractive status between urban and rural regions, of children in Korea, in the age group of 13. Methods. From October 2016 to January 2017, forty subjects( 20 male subjects, 20 female subjects; 13 years) were performed in refraction test using the Auto-Refraction. Myopia, hyperopia, astigmatism, and anisometropia were defined as spherical equivalent(SE)${\leq}-0.50$ diopters, SE ${\geq}+1.00D$, cylinder error ${\geq}0.75D$ and SE difference${\geq}1.00D$ between binocular eyes, respectively. Results. The refractive error by spherical equivalent among all subjects was myopia 76.25%, astigmatism 35%, emmetropia 16.25%, anisometropia 8.75%, and hyperopia 5%. The prevalence of myopia and astigmatism were much more common in urban than rural region although the difference was not statically significant. Emmetropia and astigmatism were much more common in rural region than urban although the difference was not statically significant. The prevalence of spherical equivalent was much common from -1.00 diopter to -4.00 diopter. On the other hand, the prevalence of myopia was much more than hyperopia. There was a statistical significance between OD and OS of rural region in the spherical equivalent power(p<.000). Also, There was a statistical significance between OD and OS of urban region in the spherical equivalent power(p<.004). Therefore, there was a significant statistical similarity between urban and rural regions on the OD and OS in the spherical equivalent power. On the other hand, There was a significant statistical similarity between urban and rural regions of the OD and OS in the astigmatism power(p<0.000). However, in the rural and urban regions there was not statistical significance in the OD and OS concerning the spherical equivalent power and astigmatism power (p>0.1). Conclusions. Myopia was the most common refractive error in Korea young children. while hyperopia was few. There was not a statistical significance as age between rural and urban at spherical equivalent power( P> 0.01). These results suggested that the analysis of the refractive status at young children can give the useful diagnosis data for the correction of visual acuity.

A Study on Children Suffering from Cerebral Palsy in Terms of ADL Evaluation (일상생활동작 평가를 통한 뇌성마비아동에 대한 연구)

  • Park Youn-ki;Lim Ho-Chan;Ahn Byung-Jub;Bae Sung-Soo
    • The Journal of Korean Physical Therapy
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    • v.1 no.1
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    • pp.27-45
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    • 1989
  • This study aims at helping cerebrally palsied children to overcome and minimize their sufferings, inducing them to perform ordinary activities of daily living for themselves by coducting ADL Tests which are fundamental activities in daily life and presenting treatment plan for their overall rehabilitation and basic data for achieving the training objective. For that purpose, 173 cerebrally palsied children were selected and given ADL performance Tests from Dec. 1987 to Oct. 1988 and the following results were obtained. 1. Correlation coefficients for each ADL category indicated significant statistical value at .01 level. 2. Correlation coefficient between school-year variable and ADL category variable was significant at .01 level. 3. Correlation between age variable and ADL variable category proved significant at .01 level as well. 4. Correlation coefficients between each category in terms of functional state of extremities were significant at .01 level. 5. The difference in ADL achievements between each category by school year were as follows ; 1) In the category of meeting nature's tall, the age span of more than 4 school years showed statistical significance. 2) In the category of putting off and on clothing, the age span of 3 school years indicated statistical significance. 3) In taking meals statistical significance was found in the age span of 4 school years. 4) In finger movements the age span of more the 4 school years indicated statistical significance. 5) In walking activities statistical significance was noticed in the age span of 2 or 3 school years. Besides, in category by school year, and exceptional case was noticed that the 6th graders were lower than the 5th graders in self-reliance rate. 6. the difference in ADL achievements by type of palsy, children of triplegia were the lowest, while those of monoplegia were the highest. 7. The difference in ADL achievements by kind of palsy, patients of athetosis showed lower rate of self-reliance than those of spasticity, and particularly the latter showed a high rate of self-reliance in taking meals$(83.5\%)$. The former were relatively low in self-reliance and lowerst in meeting nature's call $(59.8\%)$.

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A Study for the Features of Data Analysis Methods Used in Medical Research

  • Sin, Jae-Gyeong;Jang, Deok-Jun;Mun, Seung-Ho
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.2
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    • pp.257-264
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    • 2003
  • The perception of the importance of statistical methods for processing medical data in Korea's medical research and the practical use of the analysis method are insufficient. From this standpoint, in order to examine the features of the data analysis method used in the medical journals of Korea and America, we have examined the research papers which has been published in the exemplary medical journals of both countries. It showed that there was a large difference in the quantity and quality between Korea and America. Especially in the medical research of Korea, we could notice that the use of statistical methods were comparatively low. Hence the researchers in the medical area are encouraged to use more statistical methods in processing medical data.

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Effect of Communication with Mother and Depression to Headache in Children (아동의 어머니와의 의사소통과 우울이 두통에 미치는 영향)

  • Chung, Bok-Yae;Hong, Youn-Lan
    • Women's Health Nursing
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    • v.6 no.3
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    • pp.341-347
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    • 2000
  • The purpose of this study was to examine the variables such as communication with mother and depression with regard to headache in headache-suffering children. The study subjects consisted of 315 in 5th&6th grade elementary school children in T city, headache-suffering children mean children experiencing twice or more march, 2. 2000 - July. 20, 2000. The data were analyzed by SAS computer program. The results of this study were as follows: 1. The mean score for communication with mother was 73.74 in headache-free group and 70.42 in headache-suffering group and difference had statistical significance. 2. The mean score for depression was 39.43 in headache-free group and 43.03 in headache-suffering group and difference had statistical significance. This study in relation to nursing implies that there is a need to teach mothers to encourage positive communication with children and that to develop depression-reducing program to prevent headache attack in children.

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The Patterns of attachment between mother and child related to the child's Problem Behaviors (모자의 애착유형에 따른 문제행동)

  • 이정숙
    • Journal of Families and Better Life
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    • v.14 no.4
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    • pp.277-292
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    • 1996
  • The purpose of this study was to examine the relationship between infant's attachment and maternal parenting attitudes of 12 months infants and to verify the child's problem behaviors according to the patterns of attachment. There was no statistical significant difference between the maternal parenting attitudes and the patterns of infant's attachment. But the latter infants had been fed the more they showed secured attachment. Infants fostered under mothers having a good relationship with brother's family husband, and having a satisfaction of environmental factors had more secured attachment. There was the statistical significant difference between the patterns of attachment and child's problem behaviors. In securely attached children showed more immature insecure antisocial behaviors and habit disorders. As the results the maternal parenting attitude influenced infants's patterns of attachment to their mothers. And childern's problem behaviors were influenced by the patterns of attachment.

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The Effects of Different Types of Genres and Tasks on College Students' English Listening Comprehension

  • Kim, Sook-Hyun
    • English Language & Literature Teaching
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    • v.16 no.1
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    • pp.61-80
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    • 2009
  • This study investigates the effects of different types of genre and tasks on college students' English listening comprehension. 104 college students were assigned to Argumentative (AG), Causal and Evaluation (CE), and Narrative (NA) group. They report their listening comprehension through gap-filling (GF), summary (ST), and multiple-choice comprehension task (MC). Results showed that different genre groups were significantly different on overall tasks. Moreover, results from each group also presented that different mean scores on each task indicated a statistical significance. Proficiency levels, higher and lower level group, showed a significant effect for the task on listening comprehension. The results of the statistical analysis, using One-way ANOVA indicated that genre significantly affects Korean college students' listening comprehension, and implied that listening comprehension sores for each genre were also substantially different. Different genre groups resented significant different in overall listening comprehension tasks.

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An analysis of a statistical difference of acoustic Parameters' distribution between normal voice and pathological voice (병적 음성과 정상 음성의 음향학적 파라미터 분포에 대한 통계적 분석)

  • 김용주;권순복;김기련;신민철;조철우;왕수건
    • Proceedings of the IEEK Conference
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    • 2001.06d
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    • pp.249-252
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    • 2001
  • The most basic means of communication among humans is a voice. Without speaking of voice technologies, we found it is important and convenient to use a voice in everyday life. But. in consideration to speech recognition systems, we can't always desire a normal voice input as input signal to the system. Generally speaking. a pathological voice as against a normal which is a voice with a problem in the larynx. could be also special case of input voice. Of course, but the distortion of a speech signal by environmental effects i.e., noise or transmission channel was a raised problem. we will take up a pathological voices with laryngeal disease which is essential distortion factor in voice. Also, we are to find out the difference of acoustic parameters distribution between normal and pathological voice by a statistical method in our research.

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Test for Discontinuities in Nonparametric Regression

  • Park, Dong-Ryeon
    • Communications for Statistical Applications and Methods
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    • v.15 no.5
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    • pp.709-717
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    • 2008
  • The difference of two one-sided kernel estimators is usually used to detect the location of the discontinuity points of regression function. The large absolute value of the statistic imply discontinuity of regression function, so we may use the difference of two one-sided kernel estimators as the test statistic for testing null hypothesis of a smooth regression function. The problem is, however, we only know the asymptotic distribution of the test statistic under $H_0$ and we hardly expect the good performance of test if we rely solely on the asymptotic distribution for determining the critical points. In this paper, we show that if we adjust the bias of test statistic properly, the asymptotic rules hold for even small sample size situation.

Likelihood Based Confidence Intervals for the Difference of Proportions in Two Doubly Sampled Data with a Common False-Positive Error Rate

  • Lee, Seung-Chun
    • Communications for Statistical Applications and Methods
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    • v.17 no.5
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    • pp.679-688
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    • 2010
  • Lee (2010) developed a confidence interval for the difference of binomial proportions in two doubly sampled data subject to false-positive errors. The confidence interval seems to be adequate for a general double sampling model subject to false-positive misclassification. However, in many applications, the false-positive error rates could be the same. On this note, the construction of asymptotic confidence interval is considered when the false-positive error rates are common. The coverage behaviors of nine likelihood based confidence intervals are examined. It is shown that the confidence interval based Rao score with the expected information has good performance in terms of coverage probability and expected width.