• The Korean Journal of Applied Statistics
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• v.26 no.6
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• pp.1009-1018
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• 2013

Regression analysis is useful to understand the relationship of variables; however, we need to test if the slope of each regression lines is the same when comparing several populations. This paper suggests a new parallelism test for several linear regression lines. We use F-test of ANOVA and Kruskal-Wallis (1952) tests after obtaining slope estimator from a sequential slope. In addition, a Monte Carlo simulation study is adapted to compare the power of the proposed methods with those of Park and Kim (2009).

• Journal of Industrial Technology
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• v.25 no.A
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• pp.57-65
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• 2005

In this paper, for the highly plastic marine soft clay distributed in west and southern coast of Korean peninsula of Kwangyang and Busan New Port areas, correlation between compression index and other indices representing geotechnical engineering properties such as liquid limit, void ratio and natural water content were analyzed. Appropriate empirical equations of being able to estimate the compressibility of clays in the specific areas were proposed and compared with other existing empirical ones. For analyses of the data and test results, data for marine clays were used from areas of the South Container Port of the Busan New Port, East Breakwater, Passenger Quay, Jungma Reclamation and Reclamation Containment in the 3rd stage in Kwangyang. In order to find the best regression model by using the commercially available software, MS EXCEL 2000, results obtained from the simple linear regression analysis, using the values of liquid limit, initial void ratio and natural water content as independent variables, were compared with the existing empirical equations. Multiple linear regression was also performed to find the best fit regression curves for compression index and other soil properties by combining those independent variables. On the other hands, another software of SPSS for non-linear regression was used to analyze the correlations between compression index and other soil properties.

• Culinary science and hospitality research
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• v.23 no.5
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• pp.48-57
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• 2017

This study aims to analyze the relationships among brand value, brand trust, and brand loyalty of dessert cafes and to verify the mediating effect of brand trust in the relationship between brand value and loyalty. This study targeted eight dessert cafes located in Seoul, and a survey with customers aged 20 or over was conducted over 11 days from April 10th to 21th, 2017. A total of 230 self-administered questionnaires were distributed, and 205 questionnaires (89.13%) were included for the data analysis after the exclusion of 25 incomplete and unreliable responses. Every data used for analysis went through frequency analysis, reliability test, exploratory factor analysis, simple regression analysis, multiple regression analysis, mediator effect analysis, and Sobel test using the SPSS 18.0 analysis program. The study results revealed that brand value had a significant positive relationship to brand trust, and brand trust had a significant positive relationship to brand loyalty. Also, brand value had a significant positive relationship to brand loyalty, and brand trust mediated the relationship between brand value and loyalty. Based on these findings, the discussion to enhance brand loyalty of dessert cafes were suggested.

• Journal of Practical Engineering Education
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• v.14 no.2
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• pp.333-339
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• 2022

In this study, we study the effects of note-taking skills on students' academic performance, satisfaction, and concentration, and immersiveness when students are taking online classes. The Cornell note format was used for the note-taking skills. The survey result shows that note-taking skills in online class increase students' diligence, participation, and concentration. We find a strong positive correlation between the number of Cornell note submission and academic performance, and we show that the association between two is a statistically significant by using simple/multiple regression analysis. The multiple regression result shows that one unit increase in the Cornell note submission is associated with the increase in 0.253 midterm score on average. In addition, one unit increase in the Cornell note submission is associated with increase in 0.287 final exam score on average. Further, we conduct bootstrapping regression as a robustness test and show that the results are consistent with the simple/multiple regression results. These analyses show that Cornell note taking skills in online classes can be beneficial for students to improve the quality of their learning.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.4
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• pp.65-76
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• 2017

The purpose of this study was to present a prediction model that reflects crime risk area analysis, including factors and spatial characteristics, as a precursor to preparing an alternative plan for crime prevention and design. This analysis of criminal cases in high-risk areas revealed clusters in which approximately 25% of the cases within the study area occurred, distributed evenly throughout the region. This means that using a multiple linear regression model might overestimate the crime rate in some regions and underestimate in others. It also suggests that the number of deserted houses in an analyzed region has a negative relationship with the dependent variable, based on the multiple linear regression model results, and can also have different influences depending on the region. These results reveal that closure signs in a study area affect the dependent variable differently, depending on the region, rather than a simple or direct relationship with the dependent variable, as indicated by the results of the multiple linear regression model.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1225-1237
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• 2023

The purpose of this study is to find out the effect of office workers' motivation to choose clothing and makeup colors on appearance satisfaction and self-esteem. The subjects of this study were working women working in Chungcheong-do for two weeks from July 15, 2023 to July 29, 2023, and 696 sampled copies were used for the final analysis. Frequency analysis, factor analysis, reliability analysis, (one-way)ANOVA, and post-verification (Scheffe's) were handled using the SPSS 26.0 program, and office workers' clothing. Correlation analysis, simple regression, and multiple regression were performed to find out the correlation between makeup color selection motivation, and the statistical significance level was p<.I set it to 05. Through this research procedure, the following conclusions were drawn. First, it was found that the motivation of office workers to choose clothes color had a positive (+) effect on appearance satisfaction. Second, office workers' motivation for choosing makeup colors was found to have a positive (+) effect on appearance satisfaction, and physical attractiveness was found to have a positive (+) effect on situational factors. Third, it was found that the color choice of clothes of office workers had a positive (+) effect on self-esteem. Fourth, It was found that the motivation of office workers to choose makeup colors had a positive (+) effect on self-esteem.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.169.2-169.2
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• 2010

The research assesses the performance of the water-to-water heat pump system installed in Cheongju water treatment plant for cooling and heating ventilation. In summer season monthly averaged COP is ranged from 3.85 to 4.56 according to the water source temperature, and the performance is increased as the raw water temperature is dropped. While, heating performance is increased for the high temperature water source, and the monthly averaged COP is changed from 2.92 to 3.82. The correlation of the water source temperature and the heat pump performance shows a linear tendency by the simple regression of average data. In heating, the COP of heat pump system linearly rises according to the water source temperature. In comparison, the COP in cooling linearly reduces as the raw water temperature is raised. The goodness of fit at the simple regression shows the coefficient of determination 82% in cooling, 46% in heating. The electric cost of water-to-water heat pump is reduced by 40% compared to that of air source heat pump.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.5
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• pp.259-268
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• 2020

This study aims to provide empirical evidence on the causal relationship between bribery and firm innovation. To this end, we use a micro-dataset of small and medium firms in Vietnam surveyed in 2015. Given the binary nature of the dependent variable, a simple probit regression model is employed. However, as bribery variable is potentially endogenous, a simple probit regression may give biased estimates. We deal with the potential endogeneity by making use of the bivariate probit model. A property of the bivariate probit model is that it can produce efficient estimates of a typical probit model with endogenous binary explanatory variable. A Hausman-like likelihood ratio test is implemented following the estimation to test the existence of endogeneity. We find that bribery significantly undermines firm innovation. Also, firms run by household appear less innovative. The probability of innovation diminishes significantly if firm owners or managers have previous experience in firm products. As expected, larger firms seem to be more innovative. Exporters tend to be more innovative compared to non-exporters. Our findings provide support to the hypothesis that bribery is detrimental to firm innovation and, thus, innovation may be a mediating channel, through which, bribery impedes firm long-term performance.

• The Journal of Korean Academic Society of Nursing Education
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• v.12 no.2
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• pp.162-169
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• 2006

Purpose: The purpose of this study was to identify the relationship between Health Locus of Control(HLOC) and Health Promoting Behaviors(HPB) in the nursing college students. Method: Data were collected by the structured questionnaires from 485 nursing students in Gwangju. Data were analyzed by using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient and Simple regression. Result: The mean score for the HLOC of the nursing students was Internal: 23.858, Powerful others: 17.619, Chance: 15.076. The total mean score for HPB was 2.45(range 1-4). The highest score on the subscale was self-actualization(M=2.914), and the lowest was health responsibility(M=1.905). The score between HPB and HLOC-internal(r=.302, p=.000), HLOC-powerful others (r=.329, p=.000), HLOC-chance(r=.146, p=.001) showed a significantly positive correlation. By means of simple regression analysis, HLOC explained 14.3% of HPB. Conclusion: This study suggests that HLOC accounted for 14.3 % of HPB in the nursing college students.

• Journal of International Academy of Physical Therapy Research
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• v.9 no.2
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• pp.1455-1460
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• 2018

This study aimed to determine the effect of depression between the health-related quality of life and pain in elderly persons with physical disabilities. A total of 111 patients who were treated at hospital B (Seoul, Daejeon, Daegu, Gwangju, and Busan) participated in the Survey. The SF-36 Health Assessment was used to determine the quality of life of subjects, the Korean version of the Geriatric Depression Scale-Short form to assess the level of depression, and Numeric Rating Scale to determine the level of pain. To determine the moderating effect of depression on the relationship between quality of life and pain, simple regression analysis, and the Sobel test were performed. There was a significant negative correlation between health-related quality of life and pain (r<-.3, p<.05), and a significant positive correlation between depression and pain (r=.251, p<.05). Thus, health-related quality of life had a simple regression relationship with depression and pain. Depression also showed a mediating effect between health-related quality of life and pain. The results of this study suggest that depression mediates between pain and quality of life.