• Journal of Korean Elementary Science Education
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• v.24 no.3
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• pp.236-241
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• 2005

The purpose of this study was to investigate the elementary and middle school students' understanding of observation, prediction, and hypothesis in everyday and science educational contexts. The questionnaires for testing understanding of three categories were developed, which obtained Cronbach alpha .91. It was consisted of 40 questions of 10 items related to observation, prediction, and hypothesis. Thy test was administrated to 868 subjects from grade 3 to grade 9. The results showed that the each level of their understanding of observation, prediction, and hypothesis ranged between $29{\~}58\%$, $43{\~}53\%$, and $10{\~}25\%$. The level of understanding of observation and prediction showed tendency to promote increasingly from grade 3 to grade 9, but the level of hypothesis did not.

• Journal of The Korean Association For Science Education
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• v.18 no.1
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• pp.1-17
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• 1998

What does mean the statement that scientific reasoning is logical? In this study, we clarify the logical structure of the scientific explanation, prediction and the process of hypothesis testing. To simplify and identify the structure of scientific explanations and prediction more clearly, we used syllogism and presented various concrete examples. Especially, we showed that the logical structure of scientific explanation was well reflected in dynamics. Based on this analysis, it can be said that the deficit of students' understanding of dynamics is because that many scientific activities are focused on prediction rather than explanation. To explain the process of hypothesis testing, we reinterpreted the Wason's selection task as two stages: the process of prediction of experimental phenomena based on the presented hypothesis, and the process of the hypothesis testing based on the predicted experimental phenomena. And we suggested the reason of the logical fallacy of 'affirming the consequent' in science was because that many scientific relationships between the variables is one-to-one relationship, and compared this suggestion with the Lawon's multiple hypothesis theory. To check out the effect of content on the deductive reasoning, we reviewed some researches about psychology and psychology of science. And to understand the role of deductive reasoning in student's scientific activities, we reviewed researches about the analysis of students' responses in the task of conceptual change or evaluation of evidence and so on.

• Journal of the Korean Data and Information Science Society
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• v.17 no.4
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• pp.1387-1395
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• 2006

This paper considers testing for the ratio of two exponential means. We propose a solution based on a Bayesian decision rule to this problem in which no subjective input is considered. The criterion for testing is the Bayesian reference criterion (Bernardo, 1999). We derive the Bayesian reference criterion for testing the ratio of two exponential means. Simulation study and a real data example are provided.

• Communications for Statistical Applications and Methods
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• v.6 no.1
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• pp.293-303
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• 1999

When test outcomes of units are dichotomous and he infection rate is small group testing is more efficient that noe-to-one testing in estimating the true p and classifying units as infected or not. In this paper two-sided hypothesis testing and confidence intervals are derived based on the UMP(uniformly most powerful) unbiased test. The UMP unbiased approach is compared with Thompson's and Bhattacharyya et al.'s approaches by computing the length of confidence intervals and capture probabilities and shown to have a number of desirable properties. Unequal allocation one of advantages of the proposed approach is also mentioned.

• The Journal of Korean Association of Computer Education
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• v.3 no.2
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• pp.107-114
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• 2000

In this study, a program for statistics education is developed. This program deals with statistical hypothesis testing which is indispensible to demonstrate the research hypothesis. Statistical inference which is the process of using data obtained from a sample to make inference about the characteristics of a population is an essential concept to peoples to learn or use statistics. But in practice, there are many cases of wrong application and peoples think that statistics is hard to understand. Therefore, it is very important subject to teach easily and rightly statistics, specially elementary statistics. This program is developed especially for non-specialist. This program under multimedia environment which includes sound, video, animation etc. can interest students greatly. It doesn't show only the result but make it possible for students to execute the program by stages. By executing it, the students can understand the method and meaning of statistical hypothesis testing naturally.

• Communications for Statistical Applications and Methods
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• v.7 no.2
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• pp.403-414
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• 2000

A diagnostic tool for testing homogeneity for random effects is proposed in unbalanced linear mixed model based on score statistic. The finite sample behavior of the test statistic is examined using Monte Carlo experiments examine the chi-square approximation of the test statistic under the null hypothesis.

• Journal of Distribution Science
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• v.15 no.5
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• pp.29-38
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• 2017

Purpose - Prior theories predict a negative correlation between stock liquidity and dividend payout propensity. We test this hypothesis by examining the sample Korean retail firms. Research design, data, and methodology - We construct four different types of stock liquidity measures and investigate how these stock liquidity variables affect dividend payout propensity by employing the logit regression model. The retail firms listed in the KOSPI and KOSDAQ markets are analyzed from 1990 to 2015. Results - Our estimation results support the liquidity hypothesis if we adopt the stock turnover rate as the stock liquidity measure, particularly for the retail firms listed in the KOSPI markets and for non-conglomerate firms. Yet, our estimation results adopting the illiquidity measure of Amihud (2002), the proportion of non-trading day, and the volume of trading do not support the liquidity hypothesis. Conclusions - Our findings provide mixed results for the validity of stock liquidity hypothesis, which enriches the existing literature. In terms of turnover rate, the stock liquidity hypothesis holds robustly. Yet, we are not able to find any empirical evidence supporting the hypothesis if we use the other three measures of stock liquidity.

• Journal of Korean Elementary Science Education
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• v.27 no.1
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• pp.49-59
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• 2008

The purpose of this study was to invent a quotient equation which could quantitatively evaluate individual's hypothesis evaluating ability. The equation was induced by the analysis of the classification types about hypothesis evaluation knowledges generated by 15 pre-service elementary school teachers and the construction of the quotient equation on hypothesis evaluating ability. The hypothesis evaluation task administered to subjects was dealt with the woodpecker behavior. The task was initiated by generating hypothesis on the following question: 'Why don't woodpecker have brain damage after pecking wood?' Subjects then were asked to design and perform experiments for testing hypothesis. Finally they were asked to evaluate their own hypothesis based on the collected, analyzed and interpreted data. The knowledges generated from their evaluating hypothesis were analyzed by 4 major categories (richness, type, level and accuracy). Then, a general equation which could quantitatively and systematically evaluate individual's hypothesis evaluating ability was invented by an inductive process. After combining all the categories the following quotient equation was proposed; '$VQ\;=\;{\sum}(TE_n\;{\times}\;AE_n)\;{\times}\;LE$'. According to this results, woodpecker task and hypothesis evaluating ability quotient equation (VQ) which invented in this study could be applied to a practical use of measuring students' ability of scientific hypothesis evaluation.

• Journal of The Korean Association For Science Education
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• v.32 no.1
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• pp.129-145
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• 2012

This study investigated factors of creativity and interaction between factors that are revealed when gifted students designed scientific experiments. For this, we firstly developed items which required the written process of designing experiments to explore creativity factors. Then, we used these items as a part for letters of self-introduction to students who applied for 2011 correspondence education of general physics for the Korea Physics Olympiad. 513th letters of self-introduction which were analyzed to investigate factors of creativity in view of creativity definition after researchers' consultation, which specifically means a combination of divergent and convergent thinking. The results were as follows; (1) in the step of hypothesis building, we could not only find Originality and the Flexibility & Fluency, which were factors of divergent thinking, but also Coherency and Elaborateness, which were factors of convergent thinking. (2) in the step of the hypothesis testing, we could explore Originality, Flexibility & Fluency in divergent thinking and Coherency, Reliability, Clarity, Elaborateness in convergent thinking. (3) we also figured out three creativity types of gifted students from the viewpoint that creativity is a consequence of interaction between divergent thinking and convergent thinking; a) Type A showed divergent and convergent factors of creativity in the step of hypothesis building. However, type A did not include divergent factors of creativity on the process of the hypothesis testing. b) Type B had divergent and convergent factors of creativity on the process of the hypothesis testing, but it had not convergent factors of creativity on the step of hypothesis building. c) Finally, in Type C, only divergent factors of creativity appeared on the process of the hypothesis testing, but convergent factors of creativity could be found on the step of hypothesis building and hypothesis testing.

• The Journal of Industrial Distribution & Business
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• v.10 no.10
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• pp.35-44
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• 2019

Purpose - This study focuses on the continuance intention of O2O fresh agricultural products e-commerce. By literature review, this paper looks through the classical theories which are often applied to study use behavior and continuance intention on the electronic commerce area. Ultimately based on the expectancy theory, Technology acceptance model, success model as well as trust model, a model of the continuance intention of fresh products O2O electronic commerce application is established. Research design, data, and methodology - Among users Chinese consumers have been chosen who have use experience as the research objects. From October 2, 2018 to November 2, 2018, 685 questionnaires in total were collected by the online release and collection. Expect for the negative questionnaires, the remaining 650 pieces of data are statistically analyzed. The collected data were firstly be analyzed by SPSS Ver. 25 on its frequency, reliability and exploratory factors. Then AMOS Ver. 25 is applied to the Confirmatory Factor Analysis, Discriminant Validity and hypothesis testing of the Structural Equation Modeling. Finally, the following research conclusions could be obtained from the hypothesis testing. Results - Firstly, in the extended IS model, quality factor for hypothesis testing, service quality, information quality and delivery quality have obviously present positive influences on satisfaction respectively. Secondly, in the hypothesis testing part of ECM-ISC model and UTAUT model, all hypotheses have presented accepted results. Especially from expectation confirmation to usefulness perception, the influence factor achieves 12.603, In the hypothesis of continuance intention, the influence factor of social influence on continuance intention is 7.748 and also it is the most remarkable one. Conclusions - The results show that the service quality of O2O fresh agricultural products e-commerce has the greatest impact on satisfaction, while the perceived usefulness of consumers has the most significant impact on O2O fresh agricultural products for sustainable use intention. This thesis makes up for the blank of O2O fresh food e-commerce for sustainable use intentions, and provides a theoretical basis for consumers' sustainable use behavior, and practical enlightenment for the sustainable development of O2O fresh agricultural products e-commerce.