• The Korean Journal of Applied Statistics
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• v.18 no.2
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• pp.435-443
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• 2005

Coefficients of determination in logistic regression analysis are defined as various statistics, and their values are relatively smaller than those for linear regression model. These coefficients of determination are not generally used to evaluate and diagnose logistic regression model. Liao and McGee (2003) proposed two adjusted coefficients of determination which are robust at the addition of inappropriate predictors and the variation of sample size. In this work, these adjusted coefficients of determination are applied to variable selection method for logistic regression model and compared with results of other methods such as the forward selection, backward elimination, stepwise selection, and AIC statistic.

• Journal of the Korean Data and Information Science Society
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• v.22 no.4
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• pp.691-699
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• 2011

Land sliding is one of well-known nature disaster. As a part of effort to reduce damage from land sliding, many researchers worked on increasing prediction ability. However, because previous studies are conducted mostly by non-statisticians, previously proposed models were hardly statistically justifiable. In this paper, we predicted the probability of land sliding using the logistic regression model. Since most explanatory variables under consideration were correlated, we proposed the final model after backward elimination process.

• The Journal of Korean Physical Therapy
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• v.25 no.5
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• pp.330-336
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• 2013

Purpose: Respiratory is an essential vital component for conservation of life in human, which is controlled by respiratory muscles and its related neuromuscular regulation. The purpose of this study is to assess lung capacity and respiratory pressure in healthy children, and to investigate relationship and predictability between respiratory pressure and other related respiratory functions. Methods: A total of 31 healthy children were recruited for this study. Demographic information and respiratory related factors were assessed in terms of body surface area (BSA), chest mobility, lung capacity, and respiratory pressure. Correlation between respiratory pressure and the rested variables was analyzed, and multiple regression using the stepwise method was performed for prediction of respiratory muscle strength, in terms of respiratory pressure as the dependent variable, and demographic and other respiratory variables as the independent variable. Results: According to the results of correlation analysis, respiratory pressure showed significant correlation with age (r=0.62, p<0.01), BSA (r=0.80, p<0.01), FVC (r=0.80, p<0.01), and FEV1 (r=0.70, p<0.01). In results of multiple regression analysis using the backward elimination method, BSA and FVC were included as significant factors of the predictable statistical model. The statistical model showed a significant explanation power of 71.8%. Conclusion: These findings suggest that respiratory pressure could be a valuable measurement tool for evaluation of respiratory function, because of significant relationship with physical characteristics and lung capacity, and that BSA and FVC could be possible predictable factors to explain the degree of respiratory pressure. These findings will provide useful information for clinical assessment and treatment in healthy children as well as those with pulmonary disease.

• Korean Journal of Community Nutrition
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• v.18 no.4
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• pp.312-323
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• 2013

Variables affecting bone heath of growing children were analyzed among forty nine 10-12 year old elementary students in three rural regions of north west Chungnam area. Information on age of the parents, duration of breast feeding and birth weight were collected from the guardians of the participants and nutrient intake and diet quality were assessed by average of three-day food records of participants with the help of dietitians. Bone health status was measured by calceneal broadband ultrasound attenuation (BUA) using quantitative ultrasound (QUS). Results showed that anthropometic indexes and nutrient intake levels were not different between boys and girls. However, iron intake was significantly lower in girls than in boys. Girls after menarche showed lower intake levels for thiamin, riboflavin, pyridoxine and niacin than girls before menarche. z-scores of BMI were lower than -1 and higher than +1 showed shorter breast feeding period than others but the difference was statistically non-significant. Overall, the subjects did not consume enough s of calcium, vitamin C and folic acid. Zinc intake and BMI were the most significant factors affecting BUA by the results of backward elimination in multiple regression models. Phosphorous and beta-carotene intakes showed significant negative relation with BUA. This study showed that children living in the rural area of Chungnam need extra care to keep their health and nutrient intakes especially for the nutrients known to affect growth. Tailored nutrition education needs to be more focused on the improvement of bone health status of children.

• Journal of Sasang Constitutional Medicine
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• v.19 no.1
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• pp.98-115
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• 2007

1. Objectives This study focuses on the Validity of the Questionnaire about Sasang Constitution Classification for Mongolians 2. Methods By using the way of backward elimination, certain variables are chosen from the 438 cases whose physical conditions are absolutely diagnosed. After that, discriminant analysis for the selected variables has been done to obtain the physical constitution equation and the accuracy ratio of diagnosis which are useful for physical constitution diagnosis. 3. Results and Conclusions (1) In tile Validity for the Questionnaire of Sasang Constitution Classification for Mongolians, the accuracy ratio of diagnosis of Taeyangin is 100%, Soyangin 62.5%, Taeumin 76.7%, and Soeumin 66.1% respectively as a result of the discriminant analysis employing Cronbach's alpha coefficient. On the whole, the accuracy ratio of diagnosis is 70.1%. (2). In the Validity for the Questionnaire of Sasang Constitution Classification for Mongolians, the accuracy ratio of diagnosis of 70.1% means that it beats the maximum chance criterion of 41.4% and the proportional chance criterion of 34.4% by 28.7% and 35.7% respectively. Conclusively, this questionnaire has discriminant power.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.373-379
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• 2020

The purpose of this study is to investigate the factors affecting change in consumers' consumption tendency and the perception of aged meat. This study compared 2012 and 2019 results from beef consumer surveys. The importance of quality judgment criteria, taste determinants, and the perception that marbling is harmful to health were analyzed using regression analysis through the backward elimination method. As a result of the analysis, it was determined that the importance had increased for recognizing freshness, juiciness, tenderness, and ripening period, and for knowing that marbling was harmful to the health. Also shown was that the intention to purchase aged meat had an influence on whether the consumer favorably perceived the freshness, tenderness, and ripening period. This study analyzed how consumers' consumption tendencies changed to cope with these changes in consumer preferences. The basic data of the research analyzed consumption propensity, the intention to consume beef, and what factors influence the perception of mature meat. It is thought that there is a need to raise awareness about aged meat for diversification of consumer preferences and rational production and consumption in the future.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.4
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• pp.174-181
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• 2018

Objectives: The number of patients with medication-related osteonecrosis of the jaw (MRONJ) is increasing, but treatment remains controversial. Published papers and systematic reviews have suggested that surgical treatment is effective in patients with MRONJ. The purpose of this study was to determine whether preoperative University of Connecticut Osteonecrosis Numerical Scale (UCONNS), other serologic biomarkers, and size of necrosis are prognostic factors for outcome of surgical treatment in MRONJ. Materials and Methods: From January 2008 to December 2016, 65 patients diagnosed with MRONJ at the Department of Oral and Maxillofacial Surgery in College of Dentistry, Dankook University who required hospitalization and surgical treatment were investigated. Patient information, systemic factors, and UCONNS were investigated. In addition, several serologic values were examined through blood tests one week before surgery. The size of osteolysis was measured by panoramic view and cone-beam computed tomography in all patients. With this information, multivariate logistic regression analysis with backward elimination was used to examine factors affecting postoperative outcome. Results: In multivariate logistic analysis, higher UCONNS, higher C-reactive protein (CRP), larger size of osteolysis, and lower serum alkaline phosphate were associated with higher incidence of incomplete recovery after operation. This shows that UCONNS, CRP, serum alkaline phosphate, and size of osteolysis were statistically significant as factors for predicting postoperative prognosis. Conclusion: This study demonstrated that CRP, UCONNS, serum alkaline phosphate, and size of osteolysis were statistically significant factors in predicting the prognosis of surgical outcome of MRONJ. Among these factors, UCONNS can predict the prognosis of MRONJ surgery as a scale that includes various influencing factors, and UCONNS should be used first as a predictor. More aggressive surgical treatment and more definite surgical margins are needed when the prognosis is poor.

• Proceedings of the Fisheries Business Administration Society of Korea Conference
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• 2007.12a
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• pp.167-184
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• 2007

The objectives of this paper are to identify the causes of the corporate distress and to develop a distress prediction model with the financial information in fishery industry. In this study, the corporate distress is defined as economic failure and technical insolvency. Economic failure occurs by reduction, shut-down, or change of the business and technical insolvency results from failure to pay the financial debt of companies. The 33 distressed firms from 1991 to 2003 were composed by 14 economic failure companies, 15 technical insolvency companies. 4 companies applied to the both cases. The analysis of distress prediction of fishery companies were accomplished according to the distress definition. The analysis was carried out as two steps. The first step was the univariate analysis, which was used for checking the prediction power of individual financial variable. The t-test is used to identify the differences in financial variables between the distressed group and the non-distressed group. The second step was to develop distress prediction model with logistic regression. The variables showed the significant difference in univariate analysis were selected as the prediction variables. The financial ratios, used in the logistic regression model, were selected by backward elimination method. To test stability of the distress prediction model, the whole sample was divided as three sub-samples, period 1(1990$\sim$1993), period 2(1994$\sim$1997), period 3(1998$\sim$2002). The final model built from whole sample appled each three sub-samples. The results of the logistic analysis were as follows. the growth, profitability, stability ratios showed the significant effect on the distress. the some different result was found in the sub-sample (economic failure and technical insolvency). The growth and the profitability were important to predict the economic failure. The profitability and the activity were important to predict technical insolvency. It means that profitability is the really important factor to the fishery companies.

• The Journal of Fisheries Business Administration
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• v.39 no.2
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• pp.61-79
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• 2008

The objectives of this paper are to identify the causes of the corporate distress and to develop a distress prediction model with the financial information in fishery industry. In this study, the corporate distress is defined as economic failure and technical insolvency. Economic failure occurs by reduction, shut - down, or change of the business and technical insolvency results from failure to pay the financial debt of companies. The 33 distressed firms from 1991 to 2003 were composed by 14 economic failure companies, 15 technical insolvency companies. 4 companies applied to the both cases. The analysis of distress prediction of fishery companies were accomplished according to the distress definition. The analysis was carried out as two steps. The first step was the univariate analysis, which was used for checking the prediction power of individual financial variable. The t - test is used to identify the differences in financial variables between the distressed group and the non - distressed group. The second step was to develop distress prediction model with logistic regression. The variables showed the significant difference in univariate analysis were selected as the prediction variables. The financial ratios, used in the logistic regression model, were selected by backward elimination method. To test stability of the distress prediction model, the whole sample was divided as three sub-samples, period 1(1990 - 1993), period 2(1994 - 1997), period 3(1998 - 2002). The final model built from whole sample appled each three sub - samples. The results of the logistic analysis were as follows. the growth, profitability, stability ratios showed the significant effect on the distress. the some different result was found in the sub - sample (economic failure and technical insolvency). The growth and the profitability were important to predict the economic failure. The profitability and the activity were important to predict technical insolvency. It means that profitability is the really important factor to the fishery companies.

• The Journal of Korean Society for School & Community Health Education
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• v.21 no.1
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• pp.61-74
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• 2020

Objectives: This study aims to examine hypertension patients' quality of life by using the data of the 7^th Korea National Health and Nutrition Examination Survey (1^st year, 2016), identify the factors related to this, and utilize the results as basic data for intervention that can improve hypertension patients' quality of life. Methods: For the research subjects, this study extracted 1,531 patients who were diagnosed with hypertension by a doctor from the total sample of 8,150 participants of the 7^th Korea National Health and Nutrition Examination Survey, and selected 1,072 patients with no missing value in the variables to be analyzed as the final research subjects. The SPSS(version25.0) program was used for the analysis of the collected data. Then, this study used a backward elimination multiple regression analysis method that applied complex sample, to examine the factors related with the finally estimated quality of life. Results: The results of this study revealed that hypertension patients' quality of life was related with age, occupation, spouse, household income, weight gain, restriction of activity, subjected health status, perceived stress, and presence of comorbidity. The final model explained 37.0% of the variance (Wald F=30.012 p<.001). Conclusions: When an intervention program is implemented for the improvement of hypertension patients' quality of life in the future, it will be effective to construct the program according to age group, employment, marital status and household income. As for the program operation, patients should get help therefrom to control weight, facilitate activities and relieve their stress, and they should be also motivated to feel healthy. Furthermore, education should be offered so that they appropriately manage their underlying disease at an early stage.