• Annals of Occupational and Environmental Medicine
• /
• v.35
• /
• pp.49.1-49.7
• /
• 2023

The Korean Working Conditions Survey (KWCS) is a state-approved statistical survey that has been conducted by the Occupational Safety and Health Research Institute (OSHRI) every 3 years since 2006 to monitor changes in the working conditions of Koreans. This cross-sectional national survey involves a sample of 50,000 employed people aged 15 or older. KWCS measures various working conditions through > 130 survey questions, including questions regarding working hours, labor intensity, work-life balance, degree of exposure to risk factors, and subjective health status. Professional survey interviewers visit households and conduct face to face interviews. KWCS provides data and statistics for occupational safety and health polices and research in Korea. Furthermore, OSHRI holds academic conferences every year, awards high-quality academic papers, and supports researchers using data. Microdata is publicly available through the OSHRI website (https://oshri.kosha.or.kr).

• Asian Journal of Business Environment
• /
• v.6 no.1
• /
• pp.25-30
• /
• 2016

Purpose - The study aims to examine the students' perspective (stream wise) of parameters affecting the undergraduate engineering education system present in a private technical institution in NCR, Haryana, India. Research design, data, and methodology - It is a descriptive type of research in nature. Questionnaire Based Survey has been used to collect the data. The sample size for the study is 500 comprising of the students respondents. The sample has been taken randomly and the questionnaire was filled by the students (pursuing B. Tech) chosen on the random basis from a private technical educational institution in NCR, Haryana, India. For data analysis and conclusion of the results of the survey, statistical tool like F test was performed with the help of high quality software; SPSS. Conclusion - Analysis of variance revealed statistically no difference between the mean number of the groups (stream wise) for the parameters "Selection", "Academic Excellence", "Infrastructure", "Personality Development and Industry Exposure" and "Management and Administration". While Analysis of variance revealed statistically difference between the mean numbers of the groups for the parameter "Placements".

• Journal of the Korea Organic Resources Recycling Association
• /
• v.13 no.3
• /
• pp.105-118
• /
• 2005

This study examined the improvements of existing food waste statistics system using a sample survey, which estimated the total food waste generation in 4 areas(High, Middle, Middle and Low, and Low population density), and a survey, which was aimed at forming a basis for modeling 112 local governments, were conducted. Currently, the methods for collecting the statistical data are summarized as five types. In high population density areas, the type based on examining the recycling facilities was found to be a more general way of estimating population centers higher than low population density areas. It was found that numerous low population density areas estimated their food waste production according to its generation per capita. It was also found that the findings of sample survey were 10%~40% higher than the existing statistical data and Non-separated collected food waste appears to be the main factor.

• Communications for Statistical Applications and Methods
• /
• v.20 no.2
• /
• pp.97-105
• /
• 2013

Stratification (among other applications) is a popular technique used in survey practice to improve the accuracy of estimators. Its full potential benefit can be gained by the effective use of auxiliary variables in stratification related to survey variables. This paper focuses on the problem of stratum formation when multiple stratification variables are available. We first review a variance reduction strategy in the case of univariate stratification. We then discuss its use for multivariate situations in convenient and efficient ways using three methods: compromised measures of size, principal components analysis and a K-means clustering algorithm. We also consider three types of compromising factors to data when using these three methods. Finally, we compare their efficiency using data from MU281 Swedish municipality population.

• Communications for Statistical Applications and Methods
• /
• v.8 no.3
• /
• pp.719-729
• /
• 2001

Overlap Maximization is a sampling technique to reduce survey costs and costs associated with the survey. It was first studied by Keyfitz(1951). Ernst(1998) presented a remarkable procedure for maximizing the overlap when the sampling units can be selected for two identical stratified designs simultaneously, But the approach involves mimicking the behaviour of nonlinear function by linear function and so it is less direct, even though the stratification problem for the overlap corresponds directly to the linear programming problem. furthermore, it uses the controlled selection algorithm that repeatedly needs zero-restricted controlled roundings, which are solutions of capacitated transportation problems. In this paper we suggest a comparatively simple procedure to use linear programming in order to maximize the overlap. We show how this procedure can be implemented practically.

• Proceedings of the Korean Statistical Society Conference
• /
• 2001.11a
• /
• pp.191-194
• /
• 2001

In general, the imputation problems which are caused from survey nonresponse have been studied for being based on ignorable cases. However the model based approach can be applied to survey with nonresponse suspected of being nonignorable. Here in this study, we will make the nonresponse for nonignorable into ignorable cell using adjustment cell approach, then we can applied the ignorable nonresponse method. For data sets of each nonresponse cells are simulated from normal distribution.

• The Korean Journal of Applied Statistics
• /
• v.8 no.1
• /
• pp.1-7
• /
• 1995

In sample survey for the estimation of low proportion, usually a large size of sample is required for a meaningful estimator. If the cost of a sample unit is high, we have to make every effort to improve the precision of the estimator. In this study, a new efficient allocation method of sample size in stratified sampling is proposed provided we have some prior information for the stratification.

• The Korean Journal of Applied Statistics
• /
• v.21 no.3
• /
• pp.413-427
• /
• 2008

In sample design, it is usually planned by purpose and the range of the announcing statistics from the survey. After survey, getting a proper and decent statistics, applying the proper weights on the results of survey is very important and necessary. Therefore in this study, three estimation methods which are raking, BLS and general linear regression method are compared with MSE, Coverage, CV, LE and NC.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.9
• /
• pp.639-647
• /
• 2020

Entrepreneurial intention is receiving immense recognition in entrepreneurship researches, as it motives an individual to become an entrepreneur. Still, the interplay between gender perspective and contextual factors (i.e., access to capital, business information, social network, educational support, structural support) are not fully investigated in understanding the entrepreneurial intention in developing countries like Bangladesh. Therefore, the paper aims to examine the gender difference and educational discipline difference in the university's students' entrepreneurial intention in relation to contextual factors in Bangladesh. In this study, sample has been particularly taken from the different disciplinary students of private universities. Five-point Likert scale-based survey questionnaire was developed based on past researches. 280 online survey forms were distributed among the university students and finally 225 students' response were found correct as the study sample size (final survey response rate = 80%), after eliminating the incorrect survey responses. For statistical analysis SPSS 23.0 version is used. One-way ANOVA is used to measure the gender and discipline difference on entrepreneurial intention among male and female students. The results show that business information and social network will have more influence on male students' entrepreneurial intention, and comparatively, business students have more willingness to become entrepreneurs than other departmental students.

• The Korean Journal of Applied Statistics
• /
• v.36 no.4
• /
• pp.337-347
• /
• 2023

Sampling designs often use stratified sampling, where elements or clusters of the study population are divided into strata and an independent sample is chosen from each stratum. The stratification strategy consists of stratification and sample allocation, which are important issues that are repeatedly considered in survey sampling. Although a stratified multistage sample design is often used in practice, the literature tends to discuss simple sampling in terms of stratum effects or stratum efficiency. This study examines an existing stratum efficiency measure for two-stage sampling and further proposes additional stratum efficiency measures using the design effect model. The proposed measures are used to evaluate the stratification strategy of the sample design for high school students of the 4^th Korean National Environmental Health Survey (KoNEHS).