• Journal of The Korean Association For Science Education
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• v.25 no.5
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• pp.595-602
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• 2005

The purpose of this study was to test effects of the Triple Abduction Model (TAM) for improving the skills of scientific hypothesis generation in science learning. Twenty-six students were selected for the TAM group and 27 others were selected for a traditional group from one high school. Researchers developed and administered 10 TAM and traditional-style activities. The degree of hypothesis explanation was evaluated during the experimental treatment. Each Subjects' ability in scientific hypothesis generation was assessed by the Science Knowledge Generation Test A and B. Test A was used as a protest and B for a posttest. The results of this study revealed that the degree of hypothesis explanation of TAM was significantly higher than the degree of the traditional group, and the mean of the TAM group was equal to the mean of traditional group on the pretest. Additionally, the mean of the TAM group was significantly higher than the mean of the control group on the posttest. Therefore, instruction with TAM was more effective than the instruction using traditionals method for increasing students' hypothesis generation skills.

• Journal of The Korean Association For Science Education
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• v.24 no.4
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• pp.731-747
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• 2004

The scientific inquiry enterprise consists of formulating hypotheses, testing hypotheses, evaluating evidence, and revising hypothesis. Scientific inquiry in the science classrooms requires students' background experience and knowledge with the phenomenon in order to ask appropriate questions, identify and define variables operationally, formulate hypotheses, and design clear and complete experiment. The ability to test hypotheses has been postulated to play a central role in cognitive processes. The purpose of this study was to analyze what the change of the quantity and quality of the hypothesis, the rejecting or accepting of the hypothesis, and the use results in the repetitional hypothesis activity experiments. To examine the problems, this study analyzed 5 classes which were designed and administered to 16 students of the 7th grade. The results of this study showed that students preferred the engineering method to scientific method and the quality of a second hypothesis got low. The quality of the hypothesis came to be higher through a repetitional hypothesis and the number of hypothesis was reduced. The results of the experiments did not play central roles in revising hypotheses and accepting or rejecting hypothesis.

• Journal of the Korean Data and Information Science Society
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• v.25 no.2
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• pp.385-392
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• 2014

Random walk hypothesis is a hypothesis that explains theoretically the difficulty in forecasting in financial market. Various tests for the hypothesis have been developed so far but it is known that those tests suffer from low power and size distortion. In this article, a sign test based on slopes are suggested to overcome these difficulties. A simulation study is conducted to compare this test to the often used Dickey and Fuller (1979) test.

• Journal of the Korean Data and Information Science Society
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• v.21 no.2
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• pp.371-377
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• 2010

In this study, we propose two informal hypothesis tests which may be useful in determining the number of trees in a random forest for use in classification. The first test declares that a case is 'easy' if the hypothesis of the equality of probabilities of two most popular classes is rejected. The second test declares that a case is 'hard' if the hypothesis that the relative difference or the margin of victory between the probabilities of two most popular classes is greater than or equal to some small number, say 0.05, is rejected. We propose to continue generating trees until all (or all but a small fraction) of the training cases are declared easy or hard. The advantage of combining the second test along with the first test is that the number of trees required to stop becomes much smaller than the first test only, where all (or all but a small fraction) of the training cases should be declared easy.

• Communications for Statistical Applications and Methods
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• v.5 no.2
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• pp.411-416
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• 1998

A simple nonparametric test of complete or total independence is suggested for continuous multivariate distributions. This procedure first discretizes the original variables based on their order statistics, and then tests the hypothesis of complete independence for the resulting contingency table. Under the hypothesis of independence, the chi-squared test statistic has an asymptotic chi-squared distribution. We present a simulation study to illustrate the accuracy in finite samples of the limiting distribution of the test statistic. We compare our method to another nonparametric test of complete independence via a simulation study. Finally, we apply our method to the residuals from a real data set.

• ETRI Journal
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• v.18 no.3
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• pp.207-213
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• 1996

This paper proposes a new nonparametric test for testing the null hypothesis that the MRL is constant against the alternative hypothesis that the MRL is decreasing (increasing) for ramdomly censored data. The proposed test statistic is a L-statistic, and we use L-statistic theory to establish its asymptotic normality of the test statistic. We discuss the efficiency loss due to censoring and also calculate the asymptotic relative efficiencies of our test statistic with respect to the Chen, Hollander and Langberg's test for several alternatives.

• Journal of The Korean Association For Science Education
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• v.19 no.1
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• pp.117-127
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• 1999

The present study investigated Korean and the US college students' scientific reasoning skills involving hypothesis-testing skills and tested the hypothesis that hypothesis-testing skills are more advanced ones than other scientific reasoning skills investigated in this study. Seven hundred and seventy-four(774) Korean and five hundred and sixty-eight(568) the US students were sampled in university level. The Test of Scientific Reasoning was used as a scientific reasoning test. The test is consisted of two conservational reasoning, two proportional reasoning, one pendulum, two probability reasoning, two controlling variable, one correlational reasoning, and two hypothesis-testing reasoning tasks. Korean students showed a significant higher score in proportional and probability reasoning tasks than the US students. However, the Korean showed a significant lower score in conservation and correlation reasoning tasks than their American counterparts. Further, Korean and the US college students showed a notably poor performance in hypothesis-testing skills comparing with other scientific reasoning skills, which supported the hypothesis that hypothesis-testing skills are more advanced ones than other scientific reasoning skills. In addition, the Korean showed a severe deficiency in candle-burning task which required the skill that students have to design a scientific test-procedure to test theoretical hypotheses. This study also discussed on the educational implications of the results of the present study.

• Journal of Korean Academy of Nursing
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• v.27 no.1
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• pp.109-119
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• 1997

This study has been attempted to set up the strategies of the nursing which can promote the activity performance for early rehabilitation for the patients by examining the effect of the structured patient education on the early rehabilitation knowledge and activity performance of the C.V.A patients. The study method has been done by investigating the experiment group and control group in advance through the question papers and interview and observation on 65 patients who had been hospitalized at oriental medicine hospital of K Medical Center from July 1st 1995 to the end of Sep, 1995. The analysis of the collected material had been done for the homogeneity test in which general characters of experiment group and control group had been tested by X²and the homogeneity test of ADL by t-test. To test the hypothesis the t-test had been given for the difference of the early rehabilitation knowledge and activity performance between the two groups and the correlation between early rehabilitation knowledge and activity performance had been tested by Pearson's Correlation Coefficient. The result of the test of the hypothesis is as the below. 1 The 1st hypothesis “The experiment group which had received the structured education should be higher in the early rehabilitation knowledge than the control group” was supported(t=4.45. p=.000). 2. The 2nd hypothesis “The experiment group which received the structured education should be higher in the early rehabilitation activity performance than the control group”was supported(t=2.11, p=.036). 3. The 3rd hypothesis “The higher the early rehabilitation knowledge of the patient the higher the activity performance degree” was rejected (r=.1546, p=.219). In conclusion, the patients who received the structured education showed the increase in the degree of early rehabilitation knowledge and activity performance, so it has been judged that education has been prerequisite in increasing the knowledge and activity performance of early rehabilitation.

• Communications for Statistical Applications and Methods
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• v.4 no.3
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• pp.787-793
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• 1997

It is well known that the assumption of independence is ofter not valid for real data. This phenomenon has been observed empirically by many prominent scientists. In this article the sensitivity of dependence on Bayes test of a sharp null hypothesis is considered. The robustness is considered with respect to the significant level and the prior probability on the null hypothesis.

• Research in Community and Public Health Nursing
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• v.12 no.3
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• pp.773-784
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• 2001

The study was conducted to test the effectiveness of thermotherapy for high school girls who suffered from disruption in school activities through dysmenorrhea, and to study the extent of its availability in school infirmaries as one of the nursing methods. The test for the study was designed to make a contrast between half of the subjects (20) who did not receive the thermotherapy, and the rest (20) who did during the period from February 15th to April 14th, 2001. Measurements were taken of the subjects who complained of painful menstruation by a set of variables. The variables that were established and complemented by Hur, Mung-heang (1985) consist of 29 items that assess the dysmenorrhea and vitality through the symptoms of primary menstruation visually. Spsswin was used to analyze the data. The Cronbach-${\alpha}$ method was used for statistic confidence, and the test effect of both the subjects and the contrary ones was analyzed by way of T-test. The conclusions are as follow. (1) The hypothesis 1 states that the subjects with themotherapy have a lower degree of dysmenorrhea rather than the contrary ones without it. By the above assessment, there was a quantitative difference between the subjects at 39.40, and the contrary ones at 22.0. After the themotherapy, the degree of dysmenorrhea in the subjects was low indicating that there is a still 5% chance of statistic meaningful difference (t= 2.651. P= .012). As a result, the first hypothesis was accepted. (2) The hypothesis 2 states that the subjects with themotherapy have a different primary menstruation than those without. Data indicate that there was a difference of -5.95 and -4.80. The subjects showed low degrees. Since it was statistically insignificant (t=-1.398, P=.170), the second hypothesis was rejected. (3) The hypothesis 3 states that the subjects with themotherapy have a different vitality. The vitality was measured in three aspects. (1) pulse rate (/min) The hypothesis 3' states that the subjects with themotherapy have the different pulse rate from those without. Data indicate that there was no statistically meaningful difference between the two groups (t=.237, P=. 814). Therefore, the third 1st hypothesis was rejected. (2) Respiration rate The hypothesis 3' states that the subjects with themotherapy have a different respiration rate between pre-thermotherapy and post-thermotherapy. in contrast with the ones without it. The data show that there was no statistically meaningful difference (t=.133. P=.895). A little respiration rate difference was shown between pre-and post-. Likewise. the third 2nd hypothesis was rejected. (3) Blood pressure In the 3rd sub-hypothesis that there would be a difference between experimental and controlled groups was also rejected. because there was no statistically significant difference between the contracting blood pressure and the relaxing blood pressure. In terms of vitality. the pulse rate, respiration rate and blood pressure have no statistical meaning but the first two ones show the decreasing in the rate. In short, though exclusive studies focused on thermo therapy have not been conducted and the comparison can not be made, this study shows not only that the thermotherapy is very effective to dysmenorrhea, but also that it can be available in school infirmaries as one of the nursing methods.