• The Korean Journal of Applied Statistics
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• v.24 no.6
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• pp.1271-1284
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• 2011

The entropy-based test of fit for the inverse Gaussian distribution presented by Mudholkar and Tian(2002) can only be applied to the composite hypothesis that a sample is drawn from an inverse Gaussian distribution with both the location and scale parameters unknown. In application, however, a researcher may want a test of fit either for an inverse Gaussian distribution with one parameter known or for an inverse Gaussian distribution with both the two partameters known. In this paper, we introduce tests of fit for the inverse Gaussian distribution based on the Kullback-Leibler information as an extension of the entropy-based test. A window size should be chosen to implement the proposed tests. By means of Monte Carlo simulations, window sizes are determined for a wide range of sample sizes and the corresponding critical values of the test statistics are estimated. The results of power analysis for various alternatives report that the Kullback-Leibler information-based goodness-of-fit tests have good power.

• Journal of the Korean Data and Information Science Society
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• v.24 no.4
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• pp.847-856
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• 2013

In this paper, we deal with testing goodness-of-fit for normal distribution based on parametric and nonparametric entropy estimators. The minimum variance unbiased estimator for the entropy of the normal distribution is derived as a parametric entropy estimator to be used for the construction of a test statistic. For a nonparametric entropy estimator of a data-generating distribution under the alternative hypothesis sample entropy and its modifications are used. The critical values of the proposed tests are estimated by Monte Carlo simulations and presented in a tabular form. The performance of the proposed tests under some selected alternatives are investigated by means of simulations. The results report that the proposed tests have better power than the previous entropy-based test by Vasicek (1976). In applications, the new tests are expected to be used as a competitive tool for testing normality.

• Journal of the Korean Data and Information Science Society
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• v.25 no.5
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• pp.1039-1055
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• 2014

The distribution of a test statistic under a null hypothesis depends on the unknown distribution of the data and thus is unknown as well. Conditional tests replace the unknown null distribution by the conditional null distribution, that is, the distribution of the test statistic given the observed data. This approach is known as permutation tests and was developed by Fisher (Fisher, 1935). Theoretical framework for permutation tests was given by Strasser and Weber(1999). The coin package developed by Hothon et al. (2006, 2008) implements a unified approach for conditional inference via the generic independence test. Because convenient functions for the most prominent problems are available, users will not have to use the extremely flexible procedure. In this article we briefly review the underlying theory from Strasser and Weber (1999) and explain how to transform the data to perform the generic function independence test. Finally it was illustrated with a few real data sets.

• Journal of Korean Academy of Nursing
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• v.12 no.1
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• pp.25-38
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• 1982

As technological civilization and medical science has developed, standards of living have imp-roved and human life expectancy has been extended. But the incidence and mortality rate of cancer have been gradually increasing due to the pollution of the environment. Even though cancer is still a great threat to human beings, the etiology and appropriate cure forcancerhavenotyetbeendiscovered. The early detection and treatment of cancer is urgently needed. This study concentrates on the health behavior of woman regarding the papanicolau smear for early detection of cervical cancer. It was done in order to provide a direction for scientific health education materials by investigating predictors of preventive health behavior. The subjects for this study were made up of 54 woman, who comply with preventive health practices(compliant) who attended the Cervical Cancer Center of Y University Hospital in order to have tests for early detection of cervical cancer and 54 woman who did not comply with preventive health practices (noncompliant) selected from 100 housewives of I apartment, Kang Nam Ku, Seoul. The study method used, was a questionnaire for the compliance group and an interview for the noncompliance group. The period for data collection was from October 13th to October 24th. 1981. Analysis of the data was done using percentages, T-test, Pearson Correlation and Stepwise Multiple Regression. The results of study were as follows: 1. The hypotheses tested were based on the health belief model; 1) The first hypothesis,“The compliant may have more knowledge of the cervical cancer than the noncompliant”was rejected(T=-1.86, p>.05) 2) The second hypothesis,“The compliant may have a higher severity of cervical cancer than the noncompliant”was accepted (T=5.41, p<.001) 3) The third hypothesis, “The compliant may have a higher susceptability to cervical cancer than the noncompliant”was accepted(T=3.51, p<.01). 4) The fourth hypothesis,“The compliant may have more beneHt than cost'from the cervical cancer tests than the noncompliant" was accepted(T=7.46, p<.001). 5) The fifth hypothesis,“The compliant may have more health concern than the noncompliant”. was accepted(T=3.39, p<.01). These results show that severity, susceptability, benefit(over cost) and health concern influence the preventive health behavior in this Study. 2. In the correlation among variables, it was found that the knowledge of cervical cancer and the benefit(over cost) of preventive health behavior were negatively correlated(r=-2.75, p<.01), Severity of cervical cancer and benefit (over cost) of preventive health behavior were positively correlated(r=.280, p＜.01), severity and susceptability of cervical cancer were positively correlated(r= .238, p<.01), benefit(over cost) and health concern were positively correlated(r= .299, p<.01). The benefit(over cost) may be raised by increasing the severity and health concern. Therefore the compliance rate of woman may be raised through health education by increasing the benefit(over cost) of the individual. 3. The Stepwise Multiple Regression between health behavior and predictors. 1) The factor“Benefit(over cost)”could account for preventive health behavior in 34.4％ of the sample(F=55.6204 P<.01). 2) When the factor“Severity”is added to this, it accounts for 44.3% of preventive health behavior(F=41.679, p<.01). 3) When the factor“Susceptability”is also included, it accounts for 46.7% of preventive health behavior(F=30.373, p<.01). 4) When the factor “Health concern”is included, it accounts for 48.1% of preventive health behavior(F=23859, p<.05). This means that other factors appear to influence preventive health behavior, since the combination of variables explains only 48.1％ of the Preventive health behavior. Therefore further study to investigate the predictors of preventive health behavior is necessary.

• Communications for Statistical Applications and Methods
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• v.24 no.5
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• pp.519-531
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• 2017

We consider goodness-of-fit test statistics for Weibull distributions when data are randomly censored and the parameters are unknown. Koziol and Green (Biometrika, 63, 465-474, 1976) proposed the $Cram\acute{e}r$-von Mises statistic's randomly censored version for a simple hypothesis based on the Kaplan-Meier product limit of the distribution function. We apply their idea to the other statistics based on the empirical distribution function such as the Kolmogorov-Smirnov and Liao and Shimokawa (Journal of Statistical Computation and Simulation, 64, 23-48, 1999) statistics. The latter is a hybrid of the Kolmogorov-Smirnov, $Cram\acute{e}r$-von Mises, and Anderson-Darling statistics. These statistics as well as the Koziol-Green statistic are considered as test statistics for randomly censored Weibull distributions with estimated parameters. The null distributions depend on the estimation method since the test statistics are not distribution free when the parameters are estimated. Maximum likelihood estimation and the graphical plotting method with the least squares are considered for parameter estimation. A simulation study enables the Liao-Shimokawa statistic to show a relatively high power in many alternatives; however, the null distribution heavily depends on the parameter estimation. Meanwhile, the Koziol-Green statistic provides moderate power and the null distribution does not significantly change upon the parameter estimation.

• Journal of the Korean Statistical Society
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• v.30 no.1
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• pp.41-61
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• 2001

The minimum negative exponential disparity estimator(MNEDE), introduced by Lindsay(1994), is an excellenet competitor to the minimum Hellinger distance estimator(Beran 1977) as a robust and yet efficient alternative to the maximum likelihood estimator in parametric models. In this paper we define the negative exponential deviance test(NEDT) as an analog of the likelihood ratio test(LRT), and show that the NEDT is asymptotically equivalent to he LRT at the model and under a sequence of contiguous alternatives. We establish that the asymptotic strong breakdown point for a class of minimum disparity estimators, containing the MNEDE, is at least 1/2 in continuous models. This result leads us to anticipate robustness of the NEDT under data contamination, and we demonstrate it empirically. In fact, in the simulation settings considered here the empirical level of the NEDT show more stability than the Hellinger deviance test(Simpson 1989). The NEDT is illustrated through an example data set. We also define a goodness-of-fit statistic to assess adequacy of a specified parametric model, and establish its asymptotic normality under the null hypothesis.

• Genomics & Informatics
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• v.5 no.2
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• pp.61-67
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• 2007

The allele frequencies of markers as well as linkage disequilibrium (LD) can be changed in cases due to the LD between markers and the disease allele, exhibiting spurious associations of markers. To identify the true association, classical statistical tests for dealing with confounders have been applied to draw a conclusion as to whether the association of variants comes from LD with the known disease allele. However, a more direct test considering LD using estimated haplotype frequencies may be more efficient. The null hypothesis is that the different allele frequencies of a variant between cases and controls come solely from the increased disease allele frequency and the LD relationship with the disease allele. The haplotype frequencies of controls are estimated using the expectation maximization (EM) algorithm from the genotype data. The estimated frequencies are applied to calculate the expected haplotype frequencies in cases corresponding to the increase or decrease of the causative or protective alleles. The suggested method was applied to previously published data, and several APOE variants showed association with Alzheimer's disease independent from the APOE ${\varepsilon}4$ variant, rs429358, regardless of LD showing significant simulated p-values. The test results support the possibility that there may be more than one common disease variant in a locus.

• International Journal of Oral Biology
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• v.34 no.3
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• pp.137-142
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• 2009

Whole-body $\gamma$-irradiation(WBI), which produces an oxidative stress, is reported to attenuate the acute antinociceptive action of morphine (a $\mu$-opioid receptor agonist), but not DPLPE (a $\delta$-opioid receptor agonist), in mice. Recently, we also reported that antinociceptive effect of morphine, but not $\beta$-endorphin (a novel $\varepsilon$-opioid receptor agonist), was attenuated by oxidative stress. These findings prompted us to investigate the effect of WBI on the antinociception of morphine and $\beta$-endorphin in mice. Mice were exposed to WBI (5 Gy) from a $^{60}Co$ gamma-source and tested 2 hours later for antinociception produced by intracerebroventricular administration of morphine or $\beta$-endorphin using the hot water tail-immersion and the writhing tests. WBI significantly attenuated the antinociception produced by morphine only in the hot water tail-immersion test, whereas the antinociception of $\beta$-endorphin was significantly potentiated by WBI in both tests. These results demonstrate a differential sensitivity of $\mu$- and $\varepsilon$-opioid receptors to WBI, and support the hypothesis that morphine and $\beta$-endorphin administered supraspinally produce antinociception by different neuronal mechanisms.

• The Korean Journal of Applied Statistics
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• v.26 no.3
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• pp.401-411
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• 2013

This study investigates the controversial chickens-eggs dilemma and empirically performs statistical tests to examine if there exists a causality between them. Granger and Hsiao tests are applied to both level and stationary variables to identify the lead-lag relationships. Each of these test is found to have the robust result where the causality runs from eggs to chickens; in addition, the explanatory power of one variable in variations of the other appears to remain time invariant. The outcome is proved to be valid as the hypothesis test for no structural change in their relationship fails to be rejected.

• Journal of the Ergonomics Society of Korea
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• v.28 no.1
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• pp.1-7
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• 2009

As products are getting more diverse and new products are entering the market faster, customers have trouble learning how to use them. User-oriented menu structures may solve this problem. In order to design user-oriented menu structures, spreading activation theory has been studied. The spreading activation test shows that the strong associative relationship between words has shorter response times. Based on the spreading activation test, asymmetric spreading activation was introduced and a hypothesis that in a well-designed menu structure, association between upper-low menu pairs is not affected by an activation direction was tested for this study. In this study the menu of a cellular phone (Model: SPH-w2900) was extracted, and underwent 1st spreading activation tests. Then, on each menu pair, response time differences (asymmetric transition) by accuracy and directions were analyzed to find out problems in labels and improve menu structures and vocabulary. Second spreading activation tests were conducted to check whether asymmetric transitions decreased. The results showed that response time differences (asymmetric transition) for activation directions were found to be dropped significantly. Asymmetric transitions in spreading activation presented in this study will be helpful to define user-oriented menu structures.