• Korean journal of food and cookery science
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• v.6 no.4 s.13
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• pp.41-50
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• 1990

This study aimed to investigate the change in food balance and dietary patterns, caused by the growth of per capita GNP during $1962{\sim}1987$. For the purpose of this analysis, ordinary least square (OLS) was adopted. Per capita GNP was independent variable and the other factors dependent variables. The other factors included Engel coefficient, food supply, energy supply, nutrient intake and the ratio of self-supply of food. The result revealed that the some variables have (+) correlation, the some variables (-) correlation and the other variables no correlation with per capita GNP. If forecasting models are designed with these results, it will be helpful for national health and nutrition, food balance and disease prevention.

• Journal of Preventive Medicine and Public Health
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• v.24 no.1 s.33
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• pp.29-36
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• 1991

A multiple regression analysis using ordinary least square (OLS) is frequently used for the projection of health expenditure as well as for the identification of factors affecting health care costs. Data for the analysis often have mixed characteristics of time series and cross section. Parameters as a result of OLS estimation, in this case, are no longer the best linear unbiased estimators (BLUE) because the data do not satisfy basic assumptions of regression analysis. The study theoretically examined statistical problems induced when OLS estimation was applied with the time series cross section data. Then both the OLS regression and time series cross section regression (TSCS regression) were applied to the same empirical da. Finally, the difference in parameters between the two estimations were explained through residual analysis.

• Journal of the Korean Society of Food Culture
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• v.5 no.4
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• pp.481-485
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• 1990

This study is designed to forecast the characteristics in food consumption patterns under per capita GNP growth. Ordinary least square(OLS)method was employed as analyzing technique. Equation was $Y=a_0+a_1X$, in which X was per capita GNP and Y were Engel coefficient, food supply, energy supply, nutrient intake and ratio of self-supply of food. The result obtained indicates that the intake of nutrient such as protein and fat will be increased, and wheat, corn and legume are expected to be imported wholly due to lower ratio of self-supply, and rice will be over-supplied continually. Therefore, the relevant policy of government must be established in the field of supply and demand of food, and the research of sound national health should be done.

• The Pure and Applied Mathematics
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• v.27 no.2
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• pp.71-81
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• 2020

Multicollinearity is a common problem in linear regression models when two or more regressors are highly correlated, which yields some serious problems for the ordinary least square estimates of the parameters as well as model validation and interpretation. In this paper, first the problem of multicollinearity and its subsequent effects on the linear regression along with some important measures for detecting multicollinearity is reviewed, then the role of eigenvalues and eigenvectors in detecting multicollinearity are bolded. At the end a real data set is evaluated for which the fitted linear regression models is investigated for multicollinearity diagnostics.

• ETRI Journal
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• v.33 no.3
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• pp.443-453
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• 2011

This paper evaluates the efficiency of mobile content firms through a hybrid approach combining data envelopment analysis (DEA) to analyze the relative efficiency and performance of firms and principal component analysis (PCA) to analyze data structures. We performed a DEA using the total amount of assets, operating costs, employees, and years in business as inputs, and revenue as output. We calculated fifteen combinations of DEA efficiency in the mobile content firms. We performed a PCA on the results of the fifteen DEA models, dividing the mobile content firms into those having either 'asset-oriented' or 'manpower and experience-oriented' efficiency. Discriminant analysis was used to validate the relationship between the efficiency models and mobile content types. This paper contributes toward the construction of a framework that combines the DEA and PCA approaches in mobile content firms for use in comprehensive measurements. Such a framework has the potential to present major factors of efficiency for sustainable management in mobile content firms and to aid in planning mobile content industry policies.

• Journal of the Korean Home Economics Association
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• v.34 no.5
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• pp.209-222
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• 1996

The purpose of this study is to apply ratio analysis, which indicates the rate of income to total expenditure, to examine wage-earners' overspending in Korea. We use the Family Income and Expenditure Survey produced by National Statistical Office Republic of Korea and total sample size is 40,691 including households complete income reported. Through the t-test, among 17 expenditure categories, overspenders is likely to spend more on housing, apparel, medical, education, and leisure expenditures more than non-overspenders significantly. Interestingly, overspenders have more income, but less financial assets than non-overspenders. To analyze the effect of socio-demographic variables on overspending, ordinary least square is utilized. The results shows that the more educated, larger family size, and older consumer tend to overspend. The results of study are leaded into two aspects. First, overspending can be solved by consumer education with efficient financial management practice. Second, overspending may be not solved unless policies in various ways enhance the overall quality of living to lessen each household's budget constraints.

• Communications for Statistical Applications and Methods
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• v.25 no.6
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• pp.577-590
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• 2018

Employing the covariance adjustment technique, we show that in the system of two seemingly unrelated multivariate regressions the estimator of regression coefficients can be expressed as a matrix power series, and conclude that the matrix series only has a unique simpler form. In the case that the covariance matrix of the system is unknown, we define a two-stage estimator for the regression coefficients which is shown to be unique and unbiased. Numerical simulations are also presented to illustrate its superiority over the ordinary least square estimator. Also, as an example we apply our results to the seemingly unrelated growth curve models.

• Asia-Pacific Journal of Business
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• v.12 no.2
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• pp.81-95
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• 2021

Purpose - The purpose of this paper is to examine the impact of holding period of IPOs on BHAR(CAR) of IPOs in IPO process, especially focused on business relationship of underwriters and institutional investors. Design/methodology/approach - This paper collected monthly IPO fund data in KOSDAQ during 2004 to 2012 and OLS(Ordinary Least Square) was hired to analyze the data. Findings - Underwriters do allocate IPOs with high BHAR(CAR) to business-related institutional investors holding IPOs longer to make the price of IPOs stable (market-making) for underewriters. Research implications or Originality - This paper finds the impact of holding period of IPOs on BHAR(CAR) of IPOs in IPO process, especially focused on business relationship of underwriters and institutional investors in Korea.

• Asia-Pacific Journal of Business
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• v.14 no.1
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• pp.427-437
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• 2023

Purpose - The purpose of this research is to examine the impact of job satisfaction related attributes on the level of life satisfaction of individuals with disabilities. Job satisfaction related elements consist of wage level, job stability, working condition, career development, and communication. Design/methodology/approach - For the data collection, this research made use of The Korean Panel Survey of Employment for people with disabilities, with the study period consisting of 2016-2018, and the number of observations measuring 4405. For the data analysis, the ordinary least square, fixed effect, and random effect regression models were used. Findings - The results indicate that the life satisfaction of people with disabilities is positively influenced by wage satisfaction, job stability satisfaction, working condition satisfaction, career development satisfaction, and communication satisfaction. Research implications or Originality - This study informs policy makers for the design of welfare for people with disability, specifically related to their labor conditions.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.3
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• pp.295-304
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• 2008

This paper comprises two specific objectives. The first is to examine the applicability of Ordinary Kriging interpolation(OK) to finite element method that is based on variogram modeling in conjunction with different allowable limits of separation distance. The second is to investigate the accuracy according to theoretical variograms such as polynomial, Gauss, and spherical models. For this purpose, the weighted least square method is applied to obtain the estimated new stress field from the stress data at the Gauss points. The weight factor is determined by experimental and theoretical variograms for interpolation of stress data apart from the conventional interpolation methods that use an equal weight factor. The validity of the proposed approach has been tested by analyzing two numerical examples. It is noted that the numerical results by Gauss model using 25% allowable limit of separation distance show an excellent agreement with theoretical solutions in literature.