• Journal of Korean Society of Transportation
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• v.4 no.2
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• pp.37-58
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• 1986

Since 1960's there have been conducted quite numbers of origin and destination (0-D) surveys in Korea, Most of them, however, were to be said not so successful. In this paper, it was investigated that why the previous 0-D surveys were failed, and that how it could be improved. The findings of this study are: 1. The collection of sample data itself was performed relatively well, but the problem was in the improper expansion methods which were applied. 2. To improve the expansion methods, it should be performed not only the dwelling unit-based sample surveys but also commercial vehicle survey, cordon line survey, screen line counts and other auxiliary travel surveys like transit patronage survey, vehicle miles survey etc. at the same time. 3. To expand the sample surveyed data in a proper way, the adjustment factors should take a disaggregate form and also should be applied not to the specific trips, but to the specific trip makers to avoid the bias which could be caused by the application of adjustment factors in a way that has been used previously. 4. If there is no considerable change in travel patterns, we can synthesize the present 0-D data with past surveyed sample data, using present statistic data in the same way which was developed in this paper when expanding and adjusting sample data.

• Journal of the Korean Data and Information Science Society
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• v.21 no.4
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• pp.669-679
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• 2010

A sample survey design is suggested for the service satisfaction evaluation of regional education offices based on the sample size of 2009 Gyeongnam regional education offices's customer satisfaction survey. The sample design is developed to fit the goal of evaluation of individual regional offices and allocate at least the minimum sample size to each city or county in Gyeongnam to achieve the goal of the survey. The population is stratified according to the regions and the types of schools, and the sample of schools is selected with proportional to the size of classes within each stratum. Finally, each sample student is selected according to two-stage cluster sampling within each sample school. Weighting averages, weighting totals and so on can be evaluated for analysis purposes. Their variance estimates can be evaluated using re-sampling methods like BBR, Jackknife, linearization-substitution methods, which are generally used for the data from a complex sample.

• Communications for Statistical Applications and Methods
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• v.8 no.3
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• pp.739-751
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• 2001

In this paper, a sample design is studied for 2000 forestry management survey of five types forestry , tree felling, gathering of pine mushroom, growing of nut trees, growing of wild flowers, and lumbering industry. We introduce population stratification and a modified stratified cut-off sampling which deal with determination of sample size, sample allocation, and estimation of total and variance of estimator. Substitution of sample units and imputation of nonresponse units are discussed for reducing the nonsampling errors.

• Journal of the Korean Data and Information Science Society
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• v.20 no.6
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• pp.1155-1167
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• 2009

We made a new sample design for life and consciousness survey of Kyungpook people in 2007. We used the 10% sample survey data of 2005 population and housing census as a survey population. After stratification, we allocate proportionally samples within strata after examining various characteristics in previous survey, which includes economic activity state, an income level per year, and housing possession. And we calculated weight in a new sample design and derived estimators and a formula of standard error using the weights.

• Proceedings of the Korean Association for Survey Research Conference
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• 2002.06a
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• pp.67-73
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• 2002

• Journal of the Korean Statistical Society
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• v.9 no.2
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• pp.213-217
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• 1980

This paper aimed at studying an efficient sampling design of the survey for non-consignment fishery products including both marine fisheries and seaculture. An analysis was done on the relationship between precision and sample size. On the basis of the analysis, the sample size was determined to be 1,080 fishery house holds with the expected precision of 4%-5%. The molluscs and seaculture were recognized to be correlated with the non-consignment products. An attempt was made to investigate the coverage of the fish kinds by the sample about 100 fish kinds were found in the 80 selected sample villages, whereas the population includes about 120 in total. This shows that the sample represents the population with satisfaction.

• The Journal of Korean Medicine
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• v.42 no.1
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• pp.12-25
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• 2021

Objectives: The aim of this study was to investigate influencing factors of using Korean medicine services (KMS) using the 2017 Korean Medicine Utilization Survey (KMUS). Methods: Demographic statistics of the survey were summarized and influencing factors of the KMS experience and the intention to visit KMS were analyzed using logistic regression model with complex sample design. Influencing factors were specified based on Andersen's behavioral model of health care utilization and factors associated with individual recognitions of KMS. Additionally, using the ordinary logistic regression model without complex sample design, the survey data were analyzed to compare the results. Results: In the logistic regression analysis, sex, age, health condition, presence of chronic disease, a degree of knowledge about Korean Medicine, and a view about herbal medicine safety were statistically significant both in the KMS experience, and the intention to visit KMS. Marital status was statistically significant in the KMS experience, while family income, a view about the cost of KMS were statistically significant in the intention to visit KMS. Conclusion: Individual recognitions of KMS and enabling components should be considered when establishing KMS policies. In addition, future studies analyzing KMUS need to take into account the complex sample design features of the survey to avoid statistically misleading results.

• Proceedings of the Korean Association for Survey Research Conference
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• 2003.06a
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• pp.69-84
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• 2003

Main monthly household surveys conducted by National Statistical Office are economically active population survey and household expenditure survey. Samples of these two surveys are redesigned every 5 years based on Census. This paper is about sample redesign of household survey conducted in 2002 based on 2000 Census.

• The Korean Journal of Applied Statistics
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• v.17 no.3
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• pp.393-402
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• 2004

We suggest a summary of sample design for the statistical survey of E-commerce to estimate the general trend as well as the market size and investment scale of e-commerce based on the Census on Basic Characteristic of Establishments(CBCE). The sample design of this survey is composed of systematic sampling and modified cut-off method.

• The Korean Journal of Applied Statistics
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• v.24 no.2
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• pp.393-400
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• 2011

In a large scale survey, cluster sampling design in which a set of observation units called clusters are selected is often used to satisfy practical restrictions on time and cost. Especially, a two stage cluster sampling design is preferred when a strong intra-class correlation exists among observation units. The sample Primary Sampling Unit(PSU) and Secondary Sampling Unit(SSU) size for a two stage cluster sample is determined by the survey cost and precision of the estimator calculated. For this study, we derive the optimal sample PSU and SSU size when the population SSU size across the PSU are di erent by extending the result obtained under the assumption that all PSU have the same number of SSU. The results on the sample size are then applied to the $4^{th}$ Korea Hospital Discharge results and is compared to the conventional method. We also propose the optimal sample SSU (discharged patients) size for the $7^{th}$ Korea Hospital Discharge Survey.