• The Korean Journal of Applied Statistics
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• v.25 no.2
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• pp.311-319
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• 2012

The simplest and the most important distribution in survival analysis is exponential distribution. Koziol and Green (1976) derived Cram$\acute{e}$r-von Mises statistic's randomly censored version based on the Kaplan-Meier product limit estimate of the distribution function; however, it could not be practical for a real data set since the statistic is for testing a simple goodness of fit hypothesis. We generalized it to the composite hypothesis for exponentiality with an unknown scale parameter. We also considered the classical Kolmogorov-Smirnov statistic and generalized it by the exact same way. The two statistics are compared through a simulation study. As a result, we can see that the generalized Koziol-Green statistic has better power in most of the alternative distributions considered.

• Journal of the Korean Statistical Society
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• v.13 no.1
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• pp.48-56
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• 1984

This paper considers one-sample and two-sample test for the logistic function by means of Kolmororov-Smirnov type statistics. The standard tables used for the Kolmogorov-Smirnov test are valid only when the function is completely specified; but they are not valid if the parameters of function are estimated from the sample. This note presents modified tables for the Kolmogorov-Sminov type staistic. These tables can be used to test the hypothesis that a sample comes from a logistic function when shape parameter $(\alpha)$ and location parameter $(\beta)$ must be estimated from the sample by the method of maximum likelihood. Monte Carlo method is employed to calculate the criticla values of the test. The tables of the critical values are provided.

• 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.

• Research in Community and Public Health Nursing
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• v.21 no.2
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• pp.252-262
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• 2010

Purpose: Designed to examine the effects of aerobic exercise therapy on elders' physical functions. Methods: Selected from an elderly welfare center in an agricultural district located in N City. Thirty seven elders were selected in the experimental group and 38 in the control group, and all the subjects aged over 65. Collected data were statistically analyzed by SPSS/PC 12.0 Win. Detailed data analysis methods were Chi-square, Fisher's exact test, Kolmogorov-Smirnov test, t-test, Mann-Whitney u-test, paired t-test, and Wilcoxon's rank sum test. Results: The first hypothesis "The experimental group who had the aerobic exercise therapy will have greater development in lower leg muscular strength compared to the control group" was supported (t=8.95, p<.001). The second hypothesis "Aerobic exercise therapy participants will show greater development in lower leg endurance" was supported (t=6.12, p<.001). The third hypothesis "Aerobic exercise therapy participants will show greater development in flexibility" was supported (U=49.00, p<.001). The forth hypothesis "Aerobic exercise therapy participants will show greater development in balance" was supported (U=322.00, p<.001). Conclusion: The aerobic exercise therapy showed positive effects on physical functions of the elderly in a rural area.

• Communications for Statistical Applications and Methods
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• v.6 no.3
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• pp.893-900
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• 1999

We use statistical tests which are useful for two-sample problem for detecting edges in gray-level images. An edge is detected by examining changes in gray-level value between adjacent pixel neighborhoods. Some experimental results show that nonparametric detectors such as Mann-Whitney test median test and Kolmogorov-Smirnov test perform effectively in both noisy and noise-free images while parametric T test is sensitive to noise.

• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.5
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• pp.219-232
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• 2020

The slip-weakening model developed by Ohnaka and Yamashita is extended over the breakdown zone by equating the scaling relationships for the breakdown zone and the whole rupture area. For the extension, the study uses the relationship between rupture velocity and radiation efficiency, which was derived in the theory of linear elastic fracture mechanics, and the definition of f_max given in the specific barrier model proposed by Papageorgiou and Aki. The results clearly show that the extended scaling relationship is governed by the ratio of rupture velocity to S wave velocity, and the velocity ratio can be determined by the ratio of characteristic frequencies of a Fourier amplitude spectrum, which are corner frequency, f_c, and source-controlled cut-off frequency, f_max, or vice versa. The derived relationship is tested by using the characteristic frequencies extracted from previous studies of more than 130 shallow crustal events (focal depth less than 25 km, M_W 3.0~7.5) that occurred in Japan. Under the assumption of a dynamic similarity, the rupture velocity estimated from f_max/f_c and the modified integral timescale give quite similar scale-dependence of the rupture area to that given by Kanamori and Anderson. Also, the results for large earthquakes show good agreement to the values from a kinematic inversion in previous studies. The test results also indicate the unavailability of the spectral self-similarity proposed by Aki because of the scale-dependent rupture velocity and the rupture velocity-dependent f_max/f_c; however, the results do support the local similarity asserted by Ohnaka. It is also remarkable that the relationship between the rupture velocity and f_max/f_c is quite similar to Kolmogorov's hypothesis on a similarity in the theory of isotropic turbulence.

• Journal of Korean Academy of Nursing
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• v.22 no.4
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• pp.620-635
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• 1992

This study identified correlations between perceived family support and hopelessness in patients admitted to Neuro - surgical Intensive Care Units. The purpose was to enhance theoretical understanding of the relationships of these two variables. The subjects of this study were 51 patients admitted to N-lCU, at three general hospitals in Seoul. Data were collected by researcher in structured interviews from Aug. 12 to Oct. 13, 1992. The research tools were parts of the Moos Family Environment Scale and the Beck Hopelessness Scale. The general characteristic data were analyzed for frequency and percentage ; the hypothesis was tested by the pearson product Moment Correlation Coefficient. After normality tests by using Kolmogorov - Sminorvtest, and T- test, ANOVA and Mann-Whitney U test, Kruskal -Wallis test were used on the Family Support and the Hopelessness about general charcteristics. The results of the above analysis were as follows 1) The average family support score for the group was 63.61 (tool average 51) and item average was 3.74 (tool item average 3) : the family support score of this sample was higher than average. The average family cohesion score of family support was 35.25 (tool average 27) and item average was 3.91 (tool item average 3). The average family expression score of family support was 28.35 (tool average 24) and item average was 3.57 (tool average 3). In this sample, perceived family expression was lower than family cohesion. 2) The average hopelessness score was 45.88 (tool average 60) and item average was 2.29 (tool item average 3) : the hopelessness score of this sample was low in comparison to the average. 3) The hypothesis in this study was supported. The main hypothesis that the higher the perceived family support level, the lower the level Of the hopelessness, was Supported (r＝-.3869 p＝.003). The sub-hypothesis that the higher the perceived family cohesion level, the lower the level of hopelessness, was supported(r＝-.3688 p＝.004). The sub-hypothesis that the higher the perceived family expression level, the lower the level of hopelessness, was supported (r＝-.3068 p＝.014). 4) General characteristics of the objects related to family support were ‘economic status’(p＝.025) and ‘helping person’(P＝.044) : the higher the economic status, the greater the family support. When the patient identified the helping person as a spouse, family support was rated more highly. The only general characteristic related to family cohesion was ‘helping person’(p＝.041). No general characteristics were related to family expression. 5) The one general characteristic related to hopelessness was ‘education’(p＝.002) : the higher their education, the lower their hopelessness. For these ICU patients, were related perceived family support and hopelessness, and family expression level was low in comparison to family cohesion level. The perceived family support of these seriously ill patients in situational crisis may have influenced the patient's emotional reaction of hopelessness. This study concluded that nurses in the ICU confirm the family support of the patient, and involve the family as the most intimate support systems in the care of the patient to help reduce the patient's hopelessness.

• Research in Community and Public Health Nursing
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• v.31 no.3
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• pp.310-321
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• 2020

Purpose: The purpose of this study is to evaluate the effectiveness of the interpersonal caring program for young North Korean defectors which we developed based on Kim's interpersonal caring technique. Methods: This study employs a non-equivalent control group pretest-posttest design. The subjects of this study are 36 young North Korean defectors living in three areas. The participants are recruited through alternative schools, churches, and acquaintances. The experimental group consists of 20 participants and the control group consists of 16 participants. Experiments are conducted by four days. Specifically, the experiments are conducted eight times and each takes about 120 minutes. Furthermore, we run the camp for two nights and three days. We test our hypothesis by using Kolmogorov-Smirnov, Independent t-test, Paired t-test, and Independent t-test. Results: All the test statistics support our hypotheses such as self-esteem (t=1.87, p=.035), mental health (t=-1.69, p=.049), interpersonal relationships (t=1.93, p=.031), and quality of life (t=1.88, p=.034). Conclusion: We found that the interpersonal caring program developed in this study is effective in improving North Korean defectors' self-esteem, mental health, interpersonal relationships, and quality of life.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5043-5047
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• 2013

Background: This is a part of a larger effort to characterize the effects on socio-economic factors (SEFs) on cancer outcome. Surveillance, Epidemiology and End Result (SEER) bone and joint sarcoma (BJS) data were used to identify potential disparities in cause specific survival (CSS). Materials and Methods: This study analyzed SEFs in conjunction with biologic and treatment factors. Absolute BJS specific risks were calculated and the areas under the receiver operating characteristic (ROC) curve were computed for predictors. Actuarial survival analysis was performed with Kaplan-Meier method. Kolmogorov-Smirnov's 2-sample test was used to for comparing two survival curves. Cox proportional hazard model was used for multivariate analysis. Results: There were 13501 patients diagnosed BJS from 1973 to 2009. The mean follow up time (SD) was 75.6 (90.1) months. Staging was the highest predictive factor of outcome (ROC area of 0.68). SEER stage, histology, primary site and sex were highly significant pre-treatment predictors of CSS. Under multivariate analysis, patients living in low income neighborhoods and rural areas had a 2% and 5% disadvantage in cause specific survival respectively. Conclusions: This study has found 2-5% decrement of CSS of BJS due to SEFs. These data may be used to generate testable hypothesis for future clinical trials to eliminate BJS outcome disparities.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.57.2-57.2
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• 2014

Red active galactic nuclei (AGNs) are supposed to be transitional objects becoming normal AGNs in the galaxy evolution scenario. So far, ~200 red AGNs have been found by very red color in optical through NIR wavelength (e.g., r'-K >5 and J-K>1.3; Urrutia et al. 2009). Here, we compare nuclear activities of the red AGNs to those of normal AGNs to verify the evolutionary phase of the red AGNs. In order to study the nuclear activities of the red AGNs, we use broad emission lines of $P{\beta}$ ($1.28{\mu}m$) of which flux is less suppressed by a factor of 100 than the $H{\beta}$ line in the case of the red AGNs with a color excess of E(B-V)=2 mag. We use 16 red AGNs discovered in previous red AGN surveys by using SDSS, 2MASS, and FIRST (Glikman et al. 2007; Urrutia et al. 2009) at z ~0.7 for which $P{\beta}$ lines are redshifted to the sky window at ${\sim}2.2{\mu}m$. The mean Eddington ratio of the 16 red AGNs is 0.562, and that of the normal AGNs is 0.320, which indicates the red AGNs include more active black hole (BH) than the normal AGNs. To test how significantly the nuclear activities of the red AGNs and the normal AGNs are different, we perform a two-dimensional Kolmogorov-Smirnov test (K-S test) on their Eddington ratio distributions. The K-S test shows the maximum deviation between the cumulative distributions, D, is 0.48, and the probability of null hypothesis, p, is even less than 0.001. This result is consistent with a picture of that the red AGNs are in intermediate phase between the stage of merger-driven starburst galaxy and the normal AGN.