• Communications for Statistical Applications and Methods
• /
• v.6 no.1
• /
• pp.151-158
• /
• 1999

Distribution-free tests are proposed for AB/BA 2*2 cross-over design data based on placements introduced by Orban and Wolfe(1992). In this paper we suggest the homogeneity test or carry-over effects and also suggest the test for direct effects and the test for period effects under the same carry-over effects. The properties such as iterative asymptotic distribution for the proposed tests are discussed.

• Korean Journal of Digital Imaging in Medicine
• /
• v.11 no.1
• /
• pp.5-13
• /
• 2009

There are several reasons to take X-ray in case of inpatients. Some of them who cannot ambulate or have any risk if move are taken portable X-ray at their wards. Usually, in this case, many other people-patients unneeded X-ray test, family, hospital workers etc-are indirectly exposed to X-ray by scatter ray. For that reason I try to be aware of free space scatter dose accurately and make the point at issue of portable X-ray better in this study. kVp dose meter is used for efficiency management of portable X-ray equipment. Mobile X-ray equipment, ionization chamber, electrometer, solid water phantom are used for measuring of free space scatter dose. First of all the same surroundings condition is made as taken real portable X-ray, inquired amount of X-ray both chest AP and abdomen AP most frequently examined and measured scatter ray distribution of two tests individually changing distance. In the result of measuring horizontal distribution with condition of chest AP it is found that the mAs is decreased as law of distance reverse square but no showed mAs change according to direction. Vertical distribution showed the mAs slightly higher than horizontal distribution but it isnt found out statistical characteristic. In abdomen AP, compare with chest AP, free space scatter dose is as higher as five-hundred times and horizontal, vertical distribution are quite similar to chest AP in result. In portable X-ray test, in order to reduce the secondary exposure by free space scatter dose first, cut down unnecessary portable order the second, set up the specific area at individual ward for the test the third, when moving to a ward for the X-ray test prepare a portable shielding screen. The last, expose about 2m apart from patients if unable to do above three ways.

• Journal of the Korean Statistical Society
• /
• v.13 no.1
• /
• pp.32-41
• /
• 1984

An adaptive distribution-free test is proposed for testing the equality of k independent distributions against unrestricted alternatives. In this paper, several rank-sum test statistics are considered as teh components of the adaptive one. The emprical powers of the adaptive testing procedure are compared to those of the classical F test and the component tests through a Monte Carlo study. The results show that the adaptive test has good power properties over a wide class of underlying distributions.

• Communications for Statistical Applications and Methods
• /
• v.25 no.5
• /
• pp.559-568
• /
• 2018

Gene classification can involve complex order-restricted inference. Examining gene expression pattern across groups with order-restriction makes standard statistical inference ineffective and thus, requires different methods. For this problem, Roy's union-intersection principle has some merit. The M-estimator adjusting for outlier arrays in a microarray study produces a robust test statistic with distribution-insensitive clustering of genes. The M-estimator in conjunction with a union-intersection principle provides a nonstandard robust procedure. By exact permutation distribution theory, a conditionally distribution-free test based on the proposed test statistic generates corresponding p-values in a small sample size setup. We apply a false discovery rate (FDR) as a multiple testing procedure to p-values in simulated data and real microarray data. FDR procedure for proposed test statistics controls the FDR at all levels of ${\alpha}$ and ${\pi}_0$ (the proportion of true null); however, the FDR procedure for test statistics based upon normal theory (ANOVA) fails to control FDR.

• Journal of the Korean Statistical Society
• /
• v.23 no.1
• /
• pp.135-149
• /
• 1994

We discussed a comparison of distribution-free two-sample procedures based on placements or ranks. Iterative asymptotic distribution of both two-sample procedures is studies and small sample Monte Carlo simulation results are presented. Also, we proposed the Hodges-Lehmann type location estimator based on linear placement statistics.

• The Korean Journal of Applied Statistics
• /
• v.4 no.1
• /
• pp.25-32
• /
• 1991

An Asymptotically distribution-free test is considered for testing parallelism against ordered alternatives in two-way layouts. The test procedure is based on a statistic which uses Jonckheere's idea after adjusting the block effects. Large-sample properties including the efficiency and limiting distribution of the test statistic are obtained. The proposed test is compared with other tests through a small-sample Monte Carlo study.

• Journal of Korean Society for Quality Management
• /
• v.15 no.2
• /
• pp.50-54
• /
• 1987

A distribution-free rank test for parallelism of regression lines against ordered alternatives is considered. The proposed test statistic is based on the Kepner-Robinson's transformation. The null distribution of the proposed statistic is the same as that of the Wilcoxon signed rank statistic. But, the proposed procedure can be applied only to four or fewer regression lines. The results of a small-sample Monte Carlo study show that the proposed test is comparable with the parametric test in heavy tailed distributions.

• The Journal of Industrial Distribution & Business
• /
• v.9 no.2
• /
• pp.73-80
• /
• 2018

Purpose - The purpose of this study is to clarify the difference of store attributes of Korean consumers and to analyze it's influence on consumer satisfaction in duty free stores which gain ground inch by inch in the distribution chanel. And it is to find discriminative result as compared with foreign consumer. Research design, data, and methodology - Subjects for the quantitative study, quota sampling was adopted in the Lotte, Shilla downtown and airport duty free stores from the first to 15^th December 2016 and 177 questionnaires from Koreans who had purchasing experience in off line duty free store were analyzed. The data was analyzed by using factor and reliability analysis, descriptive statistics analysis, the independent sample t-test and multiple regression analysis. To test consistency, Cronbach's alpha was used. Results - The result were as follows; 1. Korean consumers consider the importance of store attributes in duty free stores in order Product, Economic Feasibility, Convenience, Promotion, and Accessibility. 2. The meaningful impactive factors of duty free store attributes on consumer satisfaction turned out Product and Promotion. 3. These results show meaningful distinction between Koreans and foreigners in terms of consumer satisfaction in duty free stores. Conclusions - A marketer who is working for duty free store consider now that price benefit can not give strong impact to Korean consumers more and should concentrate on various brand assortment even including private brand. In terms of promotion, most duty free shops put special stress on foreign consumer's wants now as highly increasing of Chinese travelers but Korean consumer's sales portion and number of visitor also are steadily increasing. Therefore, a duty free marketer should prepare the Korean-oriented services with more enhanced promotion strategies for individual and group travellers, for example, a mileage service, VIP room and social network system to satisfy Korean consumers. In order to get satisfaction from Korean consumers, it makes effort on product and promotion than accessibility, price and convenience. Due to high level influence, further study is needed to enlarge to on-line market and to develop private brands for duty free stores.

• Journal of the Korean Statistical Society
• /
• v.15 no.1
• /
• pp.9-25
• /
• 1986

In this paper we propose a distribution-free rank test for ordered alternatives in a randomized block design and investigate the properties of the proposed test. The proposed test is an extension of the Page test to allow replications in each cell. Some asymptotic properties including ARE's are investigated. A small sample Monte Carlo study was performed to compare the powers of the test considered in this paper for small samples. The results show that our proposed test is robust and efficient in the case of equally-spaced treatment effects.

• The Korean Journal of Applied Statistics
• /
• v.30 no.4
• /
• pp.513-528
• /
• 2017

Statistics are often used to test two samples if they have been drawn from the same underlying distribution. In this paper, we introduce several well-known distribution-free tests to compare distributions and conduct an extensive Monte-Carlo simulation to specify their behaviors. We consider various circumstances of when two distributions vary in (1) location, (2) scale, (3) symmetry, (4) kurtosis, (5) tail weight. A practical guideline for two-sample goodness-of-fit test is presented based on the simulation result.