• Communications for Statistical Applications and Methods
• /
• v.29 no.5
• /
• pp.547-559
• /
• 2022

For a chi-squared test, which is a statistical method used to test the independence of a contingency table of two factors, the expected frequency of each cell must be greater than 5. The percentage of cells with an expected frequency below 5 must be less than 20% of all cells. However, there are many cases in which the regional expected frequency is below 5 in general small area studies. Even in large-scale surveys, it is difficult to forecast the expected frequency to be greater than 5 when there is small area estimation with subgroup analysis. Another statistical method to test independence is to use the Bayes factor, but since there is a high ratio of data dependency due to the nature of the Bayesian approach, the low expected frequency tends to decrease the precision of the test results. To overcome these limitations, we will borrow information from areas with similar characteristics and pool the data statistically to propose a pooled Bayes test of independence in target areas. Jo et al. (2021) suggested hierarchical Bayesian pooling models for small area estimation of categorical data, and we will introduce the pooled Bayes factors calculated by expanding their restricted pooling model. We applied the pooled Bayes factors using bone mineral density and body mass index data from the Third National Health and Nutrition Examination Survey conducted in the United States and compared them with chi-squared tests often used in tests of independence.

• The Korean Journal of Applied Statistics
• /
• v.25 no.2
• /
• pp.293-300
• /
• 2012

When Binomial data are obtained, logit and logit mixed models are commonly used for small area estimation. Those models are known to have good statistical properties through the use of unit level information; however, data should be obtained as area level in order to use area level information such as spatial correlation or auto-correlation. In this research, we suggested a new small area estimator obtained through the combination of unit level information with area level information.

• Journal of Korean Society of Water and Wastewater
• /
• v.23 no.5
• /
• pp.619-630
• /
• 2009

The study area investigated in this research is Hwaseong city, Gyeonggi-Do where small scale development is currently in progress. For the last three years, we carried out the environmental and ecological assessment by using data from The Ministry of Environment and Han River Basin Environmental Office. Most of development works in Hwaseong city, Gyeonggi-Do are small scale developments which are related with factory and distribution complex based on individual laws and regulations. However, environmental and ecological assessment is not being sufficiently reflected beforehand. Especially, because the development takes place mainly in the outskirts of the city, the fine forest is continuously being damaged. We analyzed changes in green zone caused by the developments. As a result, the percentage of original green zone was decreasing while the percentage of artificial green zone was increasing. We should maintain the percentage of the original green zone in order to conserve natural environment. In the past three years, the damage of the DGN (Degree of Green Naturality, 7) area that has high conservative value was little, but, there was serious damage in the area of DGN 6. In order to conserve natural environment, political and institutional investigation should be seriously carried out for mitigation of environmental and ecological damages.

• Journal of the Korean Data and Information Science Society
• /
• v.26 no.1
• /
• pp.101-109
• /
• 2015

SMRs (standardized mortality rates) for major diseases, accidents, cancer are considered in small areas of administrative units such as Eup/Myeon/Dong from years 2005 to 2008. Due to small sample issue in small areas, the precision of directly estimated crude SMR for each area can be low. In this study, we consider the HGLM (hierarchical generalized linear model) with MRF (Markov random field) to account for the spatial correlations among the small areas. The effects of covariates for cause of mortality by Dongs in Seoul and disease maps based on the estimated SMR are presented. The results suggest how we analyze and interpret the difference in mortalities by small areas such as Dongs by revealing the spatial patterns.

• Fashion & Textile Research Journal
• /
• v.19 no.5
• /
• pp.635-645
• /
• 2017

The industry of character toys is increasing and new characters are constantly being developed. However, the development of 2D cover patterns for toys is time-consuming due to frequent pattern modifications made through trial and error. Studies are now underway to obtain 2D clothing patterns from 3D body data, however, little research has been done on 2D pattern of character toys. This study suggests efficient guidelines to develop 2D cover patterns with a reasonable accuracy and processing time. Two 3D models of a dog and rabbit were used to develop 2D cover patterns. Independent variables of this study are set as 3 levels of triangle area (small, medium, and large) that influence the efficacy of 3D and 2D pattern development. The determination of the appropriate triangular area was based on the area and shape change of the 2D pattern. A medium or large triangle area was shown to be suitable for a character dog with a smooth curved surface. However, the appropriate triangle area was small if the characteristics of the curved surface are complicated as in the case of rabbit. The head of a dog (a double-curved surface) and the curved forepaw of a rabbit (a triangular area) should be small when the characteristics of the curved surface (such as the hind leg of a rabbit having a large convex surface and a small surface area) are complicated. Grouping by 3D surface characteristics could be a suitable guideline for the triangle area selection.

• The Research Journal of the Costume Culture
• /
• v.27 no.5
• /
• pp.415-432
• /
• 2019

The purpose of the present study was to generate a list of business ethics components according to business area for small and medium-sized fashion companies. Based on the literature review, 21 components of business ethics components were identified within five business areas. Ten CEOs(Chief Executive Officers) each participated in an in-depth interview, sharing ethical and unethical cases from their own businesses. Constant comparative analysis was used to generate important business ethics components from those cases. In results, important business ethics components for each business area are: 1) using human-friendly materials, strengthening sustainable technologies, using vegan materials, concerning safe process, and reducing waste in the material production and sourcing area, 2) enhancing an efficiency in design, developing recycle/reuse designs, avoiding to copy designs, and using messages for public interest in the product design area, 3) concerning fair-trade, reducing harmful substance, saving energy, and using ethical supply channels in the distribution and logistics area, 4) acquiring certifications, promoting consumer protection, avoiding exaggerative/false advertisements, and promoting social contributions in the management and marketing area, and 5) promoting workers' rights, complying with the law, and investing on employee educations in the labor management area. All of the ethical and unethical cases of the ten companies have involved aspects of the 21 components, thereby enhancing understandings on how each issue is being seriously considered and/or handled in the small and medium-sized fashion companies. Study findings may provide a basis for development of a research model for quantitative studies and/or educational programs related to business ethics in the fashion industry.

• Journal of the Korean Data and Information Science Society
• /
• v.28 no.1
• /
• pp.207-215
• /
• 2017

In this paper we study pooling effects in Bayesian testing procedures of independence for contingency tables from small areas. In small area estimation setup, we typically use a hierarchical Bayesian model for borrowing strength across small areas. This techniques of borrowing strength in small area estimation is used to construct a Bayes test of independence for contingency tables from small areas. In specific, we consider the methods of direct or indirect pooling in multinomial models through Dirichlet priors. We use the Bayes factor (or equivalently the ratio of the marginal likelihoods) to construct the Bayes test, and the marginal density is obtained by integrating the joint density function over all parameters. The Bayes test is computed by performing a Monte Carlo integration based on the method proposed by Nandram and Kim (2002).

• Research in Community and Public Health Nursing
• /
• v.33 no.3
• /
• pp.279-289
• /
• 2022

Purpose: This is a descriptive correlation study to confirm the effect of stress and anxiety caused by COVID-19 on the quality of life of small business owners in an area under environment of COVID-19. Methods: The participants were 150 small business owners in an area. The collected data were analyzed by descriptive statistics, an independent t-test, a one-way ANOVA, Pearson's correlation coefficients, and multiple regression with the SPSS 25.0 Program. Results: The stress of small business owners averaged 3.67±0.65 out of 4 points, anxiety of COVID-19 was 2.65±0.52, and quality of life was 75.61±20.26 out of 130 points. The quality of life showed a significant negative correlation with 'fear of infection' (r=-.42, p<.001), 'difficulties caused by social distancing' (r=-.49, p<.001) in the stress subdomain, and anxiety (r=-.61, p<.001). On the other hand, stress, 'fear of infection' (r=.50, p<.001), 'difficulties caused by social distancing' (r=.60 p<.001), 'anger against others' (r=.35, p<.001) and anxiety showed positive correlation. Factors affecting the quality of life of the subjects were 'fear of infection' in the stress subdomain (β=-.23, p=.003), anxiety (β=-.45, p<.001), and residential area (J zone) (β=-.16, p=.030). These factors explained 47.0% of the variance. Conclusion: In order to enhance the quality of life of small business owners in an area, it is required to reduce stress and anxiety. In addition, it is necessary to prepare an intervention program that can reduce stress and anxiety of small business owners.

• The Korean Journal of Applied Statistics
• /
• v.16 no.2
• /
• pp.239-246
• /
• 2003

In small area estimation, Best Linear Unbaised Predictor(BLUP) can be directly implicated ,specially, in use of the time series estimation. If there are correlations between observations and error terms over the time, Kalman Filter method can be used. Therefore, using kalman Filtering technique small area estimation of total of unemployments are estimated by BLUP. And for the example of this study, Economic Active Population Survey data were used.

• Journal of the Korean Data and Information Science Society
• /
• v.12 no.2
• /
• pp.47-55
• /
• 2001

Usually estimating the means is used for statistical inference. However depending the purpose of survey, sometimes totals will give the better and more meaningful in statistical inference than the means. Here in this study, we dealt with the unemployment population of small areas with using 4 different small area estimation methods: Direct, Synthetic, Composite, Bayes estimation. For all the estimates considered in this study, the average of absolute bias and men square error were obtained in the Monte Carlo Study which was simulated using data from 1998 Economic Active Population Survey in Korea.