• Communications for Statistical Applications and Methods
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• 제23권3호
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• pp.215-230
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• 2016

The powers of some tests for independence hypothesis against positive (negative) quadrant dependence in generalized Farlie-Gumbel-Morgenstern distribution are compared graphically by simulation. Some of these tests are usual linear rank tests of independence. Two other possible rank tests of independence are locally most powerful rank test and a powerful nonparametric test based on the $Cram{\acute{e}}r-von$ Mises statistic. We also evaluate the empirical power of the class of distribution-free tests proposed by Kochar and Gupta (1987) based on the asymptotic distribution of a U-statistic and the test statistic proposed by $G{\ddot{u}}ven$ and Kotz (2008) in generalized Farlie-Gumbel-Morgenstern distribution. Tests of independence are also compared for sample sizes n = 20, 30, 50, empirically. Finally, we apply two examples to illustrate the results.

• 한국보건간호학회지
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• 제23권2호
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• pp.153-161
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• 2009

Purpose: This study was done to evaluate the differences between an experimental group and a control group of nursing students for their knowledge of CPR and their practical ability after undergoing CPR training. Method: This experiment was done with nursing students, who are divided into the experimental group (20 students) and the control group (23 students) in Chunbuk C city. The data were analyzed using the SPSS PC+ 12.0 program for the Chi-square tests, t-tests and Wilcoxon rank sum tests. Results: The 1st hypothesis, that the CPR knowledge scores for the experimental group will be higher than the scores for the control group (t=-3.934, p=<.001), was supported. On the other hand, the control group showed a conspicuous and meaningful improvement (t=-3.932, p=<.001). The 2st hypothesis, that the practical ability scores for the experimental group will be higher than the scores for the control group (t=-3.926, p=<.001), was supported. Conclusion: The CPR training in combination with theory and clinical placement is seen as a means to effectively develop the knowledge and practical ability of CPR.

• Communications for Statistical Applications and Methods
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• 제19권1호
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• pp.177-182
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• 2012

A structural break in the level as well as in the innovation variance has often been exhibited in economic time series. In this paper we propose robust unit root tests based on a sign-type test statistic when a time series has a shift in its level and the corresponding volatility. The proposed tests are robust to a wide class of partially stationary processes with heavy-tailed errors, and have an exact binomial null distribution. Our tests are not affected by the size or location of the break. We set the structural break under the null and the alternative hypotheses to relieve a possible vagueness in interpreting test results in empirical work. The null hypothesis implies a unit root process with level shifts and the alternative connotes a stationary process with level shifts. The Monte Carlo simulation shows that our tests have stable size than the OLSE based tests.

• 여성건강간호학회지
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• 제5권1호
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• pp.51-64
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• 1999

Dance movement program. Psychological wellbeing, Middle aged women, Wellbeing with depression tendency, 율동적 동작 프로그램, 우울성향 중년여성 %600an This study was designed to confirm the effects of the Dance Movement Program on psychological health in middle-age women with depression tendency. 67 women with mile to moderate depression scoring between 16-25 were selected among 235 responded to CES-D (Radloff, 1977, Cho and Kim, 1993). The 46 volunteered to participate in the study were assigned the control. 7 attritions occurred during the course of the experiment leaving thirty-nine subject : nineteen experimental and twenty control, for the final analysis. Research subjects revealed to be homogenous demographically and by health-related variables. The 50-minute Dance Movement Program was performed by the experimental group 3 times a week for eight weeks, from October 6 to November 29, 1997. Depression, life satisfaction, self efficacy were measured before and after the course of Dance Movement Program. Plasma serotonin was measured to identify its relationship with depression, Homogeneity tests revealed satisfactory level on relevant research variables. Data were analyzed by $x^2$-test, paired and unpaired t-tests. The results are as follows : 1) The hypothesis that depresson score of experimental group will decreased than control group was supported by t-test(t=2.20, P=.0021) 2) The hypothesis that life satisfaction score of experimental group will increased than control group was supported by t-test(t=1.42, P=.0049). 3) The hypothesis that self-efficacy score of experimental group will increased than control group was not supported by t-test(t=6.20, P=.0616). 4) The hypothesis that level of plasma serotonin will increased than control group was not supported by t-test(t=1.88, P=.0524) Thus, the effects of the Dance Movement Program for the improvement of psychological health gram for the improvement of psychological health for the middle-aged women with depression tendency are scientifically confirmed by this study.

• Journal of the Korean Statistical Society
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• 제25권1호
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• pp.81-94
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• 1996

This paper suggests a new criterion for testing the general linear hypothesis about coefficients in multivariate growth curve model. It is developed from a Bayesian point of view using the highest posterior density region methodology. Likelihood ratio test criterion(LRTC) by Khatri(1966) results as an approximate special case. It is shown that under the simple case of vague prior distribution for the multivariate normal parameters a LRTC-like criterion results; but the degrees of freedom are lower, so the suggested test criterion yields more conservative test than is warranted by the classical LRTC, a result analogous to that of Berger and Sellke(1987). Moreover, more general(non-vague) prior distributions will generate a richer class of tests than were previously available.

• Journal of the Korean Data and Information Science Society
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• 제21권2호
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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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• 제11권3호
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• pp.643-655
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• 2004

L$_1$-estimator in the linear regression model is widely recognized to have superior robustness in the presence of vertical outliers. While the L$_1$-estimation procedures and algorithms have been developed quite well, less progress has been made with the hypothesis test in the multiple L$_1$-regression. This article suggests computer-intensive resampling approaches, jackknife and bootstrap methods, to estimating the variance of L$_1$-estimator and the scale parameter that are required to compute the test statistics. Monte Carlo simulation studies are performed to measure the power of tests in small samples. The simulation results indicate that bootstrap estimation method is the most powerful one when it is employed to the likelihood ratio test.

• Journal of Korea Trade
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• 제26권3호
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• pp.102-116
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• 2022

Purpose - This paper empirically investigates the relationship between firm productivity and importing intermediate inputs in the Korean manufacturing sector. Design/methodology - This paper tests the two related hypotheses on the relationship between importing and productivity for a sample of Korean manufacturing firms. We test the self-selection hypothesis by comparing pre-entry levels of productivity between importers and non-importers. We test the learning-by-importing hypothesis by employing propensity score matching with differencein-differences approach. Findings - Future importers are more productive than future non-importers years before they start to import, which supports the self-selection hypothesis. In contrast, there is no strong evidence for learning-by-importing. Originality/value - This paper is the first study to explore the relationship between importing and firm-level productivity for Korean firms. The results have an important implication on trade policies to lower or raise trade barriers in imported inputs.

• 한국과학교육학회지
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• 제27권2호
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• pp.120-125
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• 2007

The purpose of the present study was to test the validity of the confirming abduction model (CAM). CAM is a process model which explains how reasoners confirm their hypothetical explicans. To test this model, 154 8th grade students were sampled from one middle school in Korea. Three types of vapor condensation hypothesis confirming tests were developed and administered to the subjects. The results of this study revealed that student confidence increased when hypothetical explicans were borrowed into experienced phenomena from questioning phenomena. These results validated CAM. According to CAM, the process. of confirming hypothetical explican is as follows: representing a questioning phenomenon, representing an experienced phenomenon that is similar to the questioning phenomenon, representing the hypothetical explican of the questioning phenomenon, comparing the questioning phenomenon with the experienced phenomenon, and borrowing the hypothetical explican as the hypothetical explican of the experienced phenomenon from the hypothetical explican of the questioning phenomenon. This study also discussed the implications of these findings for teaching and learning in science education.

• 수산경영론집
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• 제45권2호
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• pp.97-112
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• 2014

This study aimed to redefine the concept of fishing village tourism. In addition, it aimed to carry out detailed analyses of the influences of authenticity and non-authenticity of fishing village experience on tourist's satisfaction as well as the influences of tourist's experience on their satisfaction. The study evaluated responses of people who visited research target fishing villages in the East sea area(Hwasung-si Baegmi-ri) which had been rated as successful case. The evaluation was performed to analyze how tourist satisfaction would be influenced by the authenticity of the fishing village experience program based on the authenticity theory(Wang, 1999) and the experience realms theory(Pine & Gilmore, 1999). This study tried to find out realistic factors of the experience realms theory through field investigation, conducting interviews, and holding discussions. From these, the cause-and-effect structure of authenticity, tourism experience and satisfaction could be identified. The results of hypothesis tests are as follows; With respect to the relationship between authenticity and satisfaction in hypothesis I, authenticity did not have a statistically significant effect on satisfaction, while non-authenticity had a significant influence. As a result, the research hypothesis I that authenticity influences satisfaction was partially supported. Regarding hypothesis II of the link between authenticity and tourism experience, a significant effect of authenticity was found in education experience, entertainment experience for Baegmi-ri village. The effect of non-authenticity was significant on deviation experience. Consequently, hypothesis II was also partly supported. The relationship between tourism experience and satisfaction in hypothesis III was significant in education, entertainment, and deviation experiences which lends support to hypothesis III to some extent.