• The Korean Journal of Applied Statistics
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• v.26 no.3
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• pp.421-429
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• 2013

Modern statistics is used in many fields; however many users face difficulties in understanding statistical concepts. On the other hand, elementary school curriculum covers stem and leaf plot, pie chart, charts for proportional data as well as descriptive statistics including the mean. We find that an "intuitive" statistical package focused on 5-8 graders for statistical education will help future statistics users understand statistical concepts at earlier stages of their lives.

• Journal of KIISE:Software and Applications
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• v.28 no.5
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• pp.48-460
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• 2001

국어사전의 뜻풀이말은 표제어의 의미를 기술할 뿐만 아니라, 상위/하위개념, 부분-전체개념, 다의어, 동형이의어, 동의어, 반의어, 의미속성 등의 많은 의미정보를 내재하고 있다. 본 연구는 뜻풀이말에서 다양한 의미정보를 획득을 위한 기본적인 도구로서 국어사전의 뜻풀이말 구문분석기를 구현하는 것을 목적으로 한다. 이를 위해서 우선 국어사전의 뜻풀이말을 대상으로 일정한 수준의 품사 및 구문 부착 말 뭉치를 구축하고, 이 말뭉치들로부터 품사 태그 중의성 어절의 빈도 정보와 통계적 방법에 기반한 문법규칙과 확률정보를 자동으로 추출한다. 본 연구의 뜻풀이말 구문분석기는 이를 이용한 확률적 차트파서이다. 품사 태그 중의성 어절의 빈도 정보와 문법규칙 및 확률정보는 파싱 과정의 명사구 중의성을 해소한다. 또한, 파싱 과정에서 생성되는 노드의 수를 줄이고 수행 속도를 높이기 위한 방법으로 문법 Factoring, Best-First 탐색 그리고 Viterbi 탐색의 방법을 이용한다. 문법규칙의 확률과 왼쪽 우선 파싱 그리고 왼쪽 우선 탐색 방법을 사용하여 실험한 결과, 왼쪽 우선 탐색 방식과 문법확률을 혼용하는 방식이 가장 정확한 결과를 보였으며 비학습 문장에 대해 51.74%의 재현률과 87.47%의 정확률을 보였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.195-195
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• 2012

인공신경망 모형은 복잡하고 비선형의 입력과 출력 관계를 잘 반영할 수 있어서 유출 모델링에 널리 적용되어 왔다. 그러나 인공신경망 모형은 강우나 유역특성의 공간적 분포를 반영하는 것이 어려우며 물리적 개념이 결여되어 있는 단점이 있다. 본 연구에서는 유역특성과 물리적 개념을 반영할 수 있는 물리기반 모형과 인공신경망 모형의 장점들을 조합하여 물리기반 모형의 일 유출량 해석 능력을 향상하기 위하여 SWAT 모형과 인공신경망(ANN)을 연계하였다. SWAT-ANN 연계모형은 두 단계로 구성되어 진다. 첫 번째 단계에서는 관측 자료를 이용하여 SWAT 모형을 보정한다. 두 번째 단계에서는 첫 번째 단계에서 계산한 소유역별 SWAT 모형의 유출결과를 ANN의 입력자료로 이용하여 SWAT-ANN 연계모형을 구축한다. SCE-UA 최적화 방법을 적용하여 SWAT 모형의 매개변수들을 보정하였고, ANN 학습은 3층의 feed-forward 역전파 알고리즘에 기초한 Bayesian Regularization 방법을 적용하였다. ANN 은닉층의 뉴런 및 전달함수는 시행착오를 통하여 적절한 ANN 구조를 설정하여 SWAT-ANN 연계모형의 일유출량을 모의하였다. 여러 가지 통계적 오차기준을 이용하여 보청천 유역에서 SWAT-ANN 연계모형의 결과와 SWAT 단독 모형의 결과를 비교하였다. SWAT-ANN 연계모형이 SWAT 단독 모형보다 더 우수한 결과를 나타내어 일 유출량 해석을 위한 SWAT-ANN 연계모형의 유용성을 확인할 수 있었다.

• Clinics in Shoulder and Elbow
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• v.16 no.1
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• pp.58-62
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• 2013

Purpose: Among the numerous clinical researches and following articles, there are few cases that apply proper methodology, which guarantees high reliability. By understanding the right concept and randomization of proper methods, research bias could be minimized. Materials and Methods: By reviewing the recently published articles about randomization, the basic concept and the necessity of applying the technique was described. Then proper methodologies for good randomization such as simple randomization, permuted-block randomization, and stratification were briefly introduced with examples. Results and Conclusion: Randomization lowers the possibility of bias and leads to higher reliability in clinical research. To obtain more reliable research results, understanding the right concept and proposition of proper methodologies of randomization is essential for researchers.

• School Mathematics
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• v.17 no.3
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• pp.515-530
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• 2015

The concepts of sample and sampling are central to make a statistically correct decision, so we need to be emphasized their importance in the statistics education. Nevertheless, there were not enough studies which discuss how to teach the concepts of sample and sampling. In this study, teaching sample and sampling is addressed by foreign curricula and cases of instruction in order to obtain suggestions for teaching sample and sampling. In particular, the curricular of Australia, New Zealand, England and the United States are analyzed, considering the sample representativeness and the sampling variability; the two elements in the concept of sample. Also foreign textbooks and cases of instruction when it comes to teach sample are analyzed. The results say that with respect to teach sample can be divided into four suggestions: first, sample was taught in the process of statistical inquiry such as data collection, analysis, and results. Second, sample was introduced earlier than Korea curriculum. Third, when it comes to teach sample, sample variability, as well as sample representativeness was considered. Fourth, technological tools were used to enhance understanding sample.

• 한국체육학회지인문사회과학편
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• v.54 no.5
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• pp.207-219
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• 2015

The purpose of this study was to test the validation of the Korean version of the Talent Development Environment Questionnaire for sport(TDEQ; Martindale et al., 2010), developed through the conceptual and statistical verification stages(substantive stage-structural stage-external stage). In accordance with the procedure of translation, the substantive concepts of the items were reviewed. The data were collected from a sample of 244 ; 117 high school student-athletes and 127 university student-athletes. In order to test the internal structure of TDEQ, EFA/CFA, and internal consistency were performed. As a result, Korean version of the TDEQ had 5 factors with 38 items. External relationship by correlation analysis and group differentiation analysis were obtained to enhance the validity of the test. Overall, the Korean TDEQ will be used as a diagnostic and evaluation tool at the stage of detection, identification, selection, and development of Sport Talent.

• The Journal of Society for e-Business Studies
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• v.22 no.1
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• pp.15-35
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• 2017

The method of weighted sum of evaluation using AHP is widely used in feasibility analysis and alternative selection. Final scores are given in forms of weighted sums and the alternative with largest score is selected. With two alternatives, as in feasibility analysis, the final score greater than 0.5 gives the selection but there remains a question that how large is large enough. KDI suggested a concept of 'grey area' where scores are between 0.45 and 0.55 in which decisions are to be made with caution, but it lacks theoretical background. Statistical testing was introduced to answer the question in some studies. It was assumed some kinds of probability distribution, but did not give the validity on them. We examine the various cases of weighted sum of evaluation score and show why the statistical testing has to be introduced. We suggest a non-parametric testing procedure which does not assume a specific distribution. A case study is conducted to analyze the validity of our suggested testing procedure. We conclude our study with remarks on the implication of analysis and the future way of research development.

• Journal of the Korean School Mathematics Society
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• v.22 no.4
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• pp.501-520
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• 2019

This study compared and analyzed Korean, American, Singaporean, and Japanese middle school mathematics curriculum standards and the learning contents in statistics. Through a comparative analysis of the curriculums of these four countries, I found several overall features and differences between the curriculums. First, all four countries emphasized statistical education in a real-life context. Second, all four countries emphasized the use of technological tools. Third, there is a middle school grade in which only Korea does not deal with statistical domains. Fourth, the statistical areas of the United States, Singapore, and Japan focused on identifying trends or variability in data distribution. Fifth, I have found some contents that only Korea does not deal with. Based on this, the following recommendations were developed for the development of the next curriculum and new textbooks in Korea. First, the statistics curriculum should be changed from one that focuses on understanding statistical concepts to one that focuses on statistical activity that utilizes these concepts. Second, in terms of middle school statistical curriculum contents, the addition of interquartile range (IQR) and box plots as learning contents should be considered. IQR and box plots are simple and practical techniques for the comparison of multiple sets of data that can be easily learned and drawn by middle school level students and applied to real-life-related statistical data to expand statistical literacy. Through this study, it is suggested that IQR and box plots need to be included in the statistical curriculum of middle schools in Korea.

• Journal of Educational Research in Mathematics
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• v.23 no.4
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• pp.467-490
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• 2013

Correlation is a basic statistical concept which is necessary for understanding the relationship between two variables when they change values. In the middle school curriculum of Korea, only informal definition of correlation is taught with two-way data representations such as scatter plots and contingency tables. In this study, we investigated Korean high school students' understanding of correlation using a test consisting of 35 items about interpretation of scatter plot, contingency table, and text in realistic situation. 216 students from a high school in Seoul took the test for 20 minutes. From the results, we could observe the following: First, students did not have right criteria for determining the strength of correlation presented in scatter plots. Most of students could determine if there is correlation/no correlation and if the correlation is positive/negative by seeing the data presented in scatter plots. However, they did not judge by the closeness to the regression line but rather judged by the closeness between data points. Second, when statements about comparing the strength of correlation in the context of real life situation were given in text, the students had difficulty in understanding the distribution-related characteristic of the bi-variate data. Students had difficulty in figuring out the local distribution characteristic of data, which cannot be guessed merely based on the expression 'The correlation is strong' without statistical knowledge of correlation. Third, a large number of students could not judge the association between two variabels using conditional proportions when qualitative data are given in 2-by-2 tables. They made judgement by the absolute cell count and when the marginal sum of two categories are different for explanatory variable they thought the association could not be determined. From these results, we concluded that educational measures are required in order to remove such misconceptions and to improve understanding of correlation. Considering that the current mathematics curriculum does not cover the concept of correlation, we need to improve the curriculum as well.

• The Journal of Engineering Geology
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• v.6 no.1
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• pp.45-49
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• 1996

It is shown that the concept of 'earthquake quanta' proposed by Sacks and Rydeleck (1995) may be expressed in a more general form. The property that for large earthquakes the stress drop is approximately a constant, while for small events the stress drop is proportional to the moment seems independent of the failure criteria of the earthquake quanta. The physical significance of the concept of earthquake quanta is discussed in the perspective of 'seismon'.