• Title/Summary/Keyword: marginal effects

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Assessing Tourists' Restaurant Preferences within Tourism Area (관광 지역 음식점에 대한 관광객들의 선호도 평가)

  • Kang, Jong-Heon;Jeong, Hang-Jin
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.2
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    • pp.165-171
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    • 2008
  • The purpose of this study was to measure tourists' preference for alternative restaurants with different combinations of attribute levels: grown area logo, origin description, traditional food, fusion food, national food, and price. A total of 210 questionnaires were completed. A conjoint experimental method was used to develop hypothetical restaurants, and an ordinal probit model was used to measure the effects of the attribute levels on tourists' preference. The ordinal probit model analysis results for the data indicated an excellent model fit. The effects of the attribute levels on tourists' preferences were statistically significant. As expected, estimates of the marginal willingness to pay were statistically significant Moreover, the tourists were more willing to pay for grown area logo as compared to the other attribute levels. The tourists also considered the grown area logo as a very important attribute. Withe regard to developing and testing conjoint models in the design of choice experiments involving multifactor alternatives, this study may approach a deeper understanding of the conjoint experiment. Greater understanding of the conjoint experiment can improve the managerial diagnoses of the problems as well as the opportunities for different marketing strategies including local branding programs and menu development and marketing communications.

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Random Parameter Negative Binomial Models of Interstate Accident Frequencies on Interchange Segment by Interchange Type/Region (RPNB 모형을 이용한 고속도로 인터체인지 구간에서의 교통사고모형 - 인터체인지 형태별/지역별로)

  • Lee, Geun Hee;Park, Minho;Roh, Jeonghyun
    • International Journal of Highway Engineering
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    • v.16 no.5
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    • pp.133-142
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    • 2014
  • PURPOSES : The objective was to develop the advanced method which could not explain each observation's specific characteristic in the present negative binomial method that results in under-estimation of the standard error(t-value inflation) and affects the confidence of whole derived results. METHODS : This study dealt with traffic accidents occurring within interchange segment on highway main line with RPNB(Random Parameter Negative Binomial) method that enables to take account of heterogeneity. RESULTS : As a result, AADT and lighting installation type on the road were revealed to have random parameter and in terms of other geometric variables, all were derived as fixed parameter(same effect on every segment). Also, marginal effects were adapted to analyze the relative effects on traffic accidents. CONCLUSIONS : This study proves that RPNB method which considers each observation's specific characteristics is better fitted to the accident data with geometrics. Thus, it is recommended that RPNB model or other methods which could consider the heterogeneity needs to be adapted in accident analysis.

The Effects of the Level of Health Literacy and Self-care Activities on Quality of Life of Patients with Diabetes in Korea (당뇨병 환자의 헬스 리터러시 수준과 자기 간호행위가 삶의 질에 미치는 영향)

  • Kang, Soo Jin;Park, Chanho
    • Research in Community and Public Health Nursing
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    • v.31 no.2
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    • pp.189-198
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    • 2020
  • Purpose: The purpose of this study was to identify levels of health literacy and examine the effects of health literacy and self-care activities on quality of life of patients with type 2 diabetes. Methods: A cross sectional design was used. Questionnaires were administered via the Gallup to 500 Korean patients with diabetes in Seoul and Gyeonggi areas. The data were analyzed using descriptive statistics, independent t tests, one way ANOVA, and hierarchical regression. Results: Of 500 patients, 12.4% (n=62) indicated 'inadequate' health literacy, and 43.8% (n=219) reported 'marginal' or 'adequate' health literacy. Levels of health literacy significantly differed by demographic characteristics, self-care activities, and quality of life. The factors that had a significant effect on quality of life included inadequate health literacy (B=3.63, p=.042) and marginal health literacy (B=3.84, p=.002); however, no significant relationship was found for self-care activities (B=0.01, p=.827). Conclusion: The results of this study demonstrate a need for further research with large samples using Korean Health Literacy Scale for Diabetes Mellitus to establish the relationships between health literacy, diabetes self-care activities, and quality of life.

Success rate and marginal bone loss of Osstem USII plus implants; Short term clinical study (Osstem USII plus 임플란트의 단기간 성공률 및 변연골 흡수량 평가)

  • Kim, Sun-Keun;Kim, Jee-Hwan;Lee, Keun-Woo;Cho, Kyoo-Sung;Han, Dong-Hoo
    • The Journal of Korean Academy of Prosthodontics
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    • v.49 no.3
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    • pp.206-213
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    • 2011
  • Purpose: The aim of this study was to evaluate the clinical value of Osstem$^{(R)}$ USII plus system implants. Clinical and radiographic data were analyzed for 88 implants placed and functionally loaded for a 12 month period at the Yonsei University Dental Hospital. Materials and Method: Based on the patient's medical records, clinical factors and their effects on implant marginal bone resorption, distribution and survival rate were analyzed. The marginal bone loss was evaluated at implant placement and during a 6 to 12 months functional loading period. The independent sample t-test was used to evaluate the interrelationship between the factors (${\alpha}$=0.05), and one way repeated measures ANOVA was used to compare the amount of marginal bone resorption. Results: The cumulative survival rate for 88 implants was 100%. The marginal bone resorption from implant placement to prosthetic delivery was 0.24 mm and the average marginal bone resorption from prosthetic delivery to 12 months of functional loading was 0.19 mm. The total average bone resorption from implant placement to 12 months of functional loading was 0.43 mm. There were no statistically differences in the amount of marginal bone resorption when implants were placed in the maxilla or the mandible (P>.05), however, implants placed in the posterior areas showed significantly more marginal bone loss than those placed in the anterior areas (P<.05). Conclusion: Based on these results, the short term clinical success rate of RBM surface treated external connection domestic implants showed satisfactory results and the marginal bone loss was in accord with the success criteria of dental implants.

Analysis of Milk Demand System (원유수급 및 우유 소비구조 분석)

  • Jeong, Min-Guk
    • Journal of Dairy Science and Biotechnology
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    • v.23 no.1
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    • pp.39-47
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    • 2005
  • This paper is intended to estimate demand for milk using POS data. POS databases were taken from various retail store across the country that account for 5 percent. Own price elasticities are negative and most milk products are statistically significant. Advertising effects are marginal, and statistically significant except flavored milk. Seasonality is apparent from July through september except children's milk.

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Benzochloroporphyrin Derivative Induced Cytotoxicity and Inhibition of Tumor Recurrence During Photodynamic Therapy for Osteosarcoma

  • Gong, Hai-Yang;Sun, Meng-Xiong;Hu, Shuo;Tao, Ying-Ying;Gao, Bo;Li, Guo-Dong;Cai, Zheng-Dong;Yao, Jian-Zhong
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.3351-3355
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    • 2013
  • Photodynamic therapy (PDT) is a promising cancer treatment modality that uses dye-sensitized photooxidation of biologic matter in target tissue. This study explored effects of the photosensitizer BCPD-17 during PDT for osteosarcoma. LM-8 osteosarcoma cells were treated with BCPD-17 and cell viability after laser irradiation was assessed in vitro with the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. The effects of BCPD-17 during PDT recurrence were then examined on tumor-bearing mice in vivo. BCPD-17 had dosedependent cytotoxic effects on LM-8 osteosarcoma cells after laser irradiation which also had energy-dependent effects on the cells. The rate of local recurrence was reduced when marginal resection of mice tumors was followed by BCPD-17-mediated PDT. Our results indicated BCPD-17-mediated PDT in combination with marginal resection of tumors is a potentially new effective treatment for osteosarcoma.

The Effect of Vocational Training on Employment Outcome in Korea's Training Credit Program (내일배움카드제 훈련이 취업성과에 미치는 영향)

  • Kim, Yong-seong
    • Journal of Labour Economics
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    • v.43 no.1
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    • pp.1-34
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    • 2020
  • As the economic environment rapidly changes, the ability to flexibly adapt has become a vital skill which is primarily attained through education and training. Subsequently, it is essential that the effects of vocational eduction and training are closely examined to see if they are fulfilling their goals; specifically, whether they bolster the chances of gaining employment. To that end, the endogenous aspects of training variables must be controlled. This study critically assesses the approaches of current literature in regards to tackling the endogeneity issue, and investigates the effects of vocational training through various econometric models. The results failed to reveal any positive effects of Korea's vocational training on employment. However, the negative effects were also not large enough to be significant. Additionally, the marginal effects were weaker for women and older age groups-which show a disparity between men and women-than for men and younger age groups, respectively. A more comprehensive and in-depth analysis will be needed of these results using recent data and detailed information about the training process.

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Review and discussion of marginalized random effects models (주변화 변량효과모형의 조사 및 고찰)

  • Jeon, Joo Yeong;Lee, Keunbaik
    • Journal of the Korean Data and Information Science Society
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    • v.25 no.6
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    • pp.1263-1272
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    • 2014
  • Longitudinal categorical data commonly occur from medical, health, and social sciences. In these data, the correlation of repeated outcomes is taken into account to explain the effects of covariates exactly. In this paper, we introduce marginalized random effects models that are used for the estimation of the population-averaged effects of covariates. We also review how these models have been developed. Real data analysis is presented using the marginalized random effects.

Analysis of Factors Influencing the Intention of New Technology Adoption -Focusing on the Pilot Project on 'Bean Stinkbug Trap'- (신기술 도입의향에 관한 영향요인 분석 - '콩 노린재 포획트랩'시범사업을 중심으로 -)

  • Yun, Jin-Woo;Chae, Yong-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.1
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    • pp.448-456
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    • 2020
  • This study found that it is critical to consider farmers' intention to adopt new technology in order to facilitate the spread of new technology. Based on this assumption, the research team analyzed the following: factors that influence intention of adoption and marginal effects on those factors. The data were collected from 99 farmers who did not participate in the pilot projects on dissemination of new technologies developed by the Rural Development Administration (RDA). A total of 19 observed variables were set to measure seven latent variables: educational support; technical support; funding support; compatibility; trialability; observability; and antipathy. The intention to adopt new technology was established as the dependent variable. According to the ordered logit analysis, educational support, observability, and antipathy were found to have significantly affected the intention to adopt new technology; their odds ratio were 6.938, 2.716, and 0.501, respectively. According to the marginal analysis, educational support, observability, and antipathy were found to have significantly affected the intention to adopt new technology; their marginal effects were 20.2 %, 10.4 %, and -7.2 %, respectively. Therefore, this study suggests the following to facilitate the spread of new technology: first, provide quality support services through effective deduction; second, increase the visibility of new technology; and third, enhance the credibility of agricultural institutions by developing continuous relations with farmers to reduce their antipathy.

Random Effects Models for Multivariate Survival Data: Hierarchical-Likelihood Approach

  • Ha Il Do;Lee Youngjo;Song Jae-Kee
    • Proceedings of the Korean Statistical Society Conference
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    • 2000.11a
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    • pp.193-200
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    • 2000
  • Modelling the dependence via random effects in censored multivariate survival data has recently received considerable attention in the biomedical literature. The random effects models model not only the conditional survival times but also the conditional hazard rate. Systematic likelihood inference for the models with random effects is possible using Lee and Nelder's (1996) hierarchical-likelihood (h-likelihood). The purpose of this presentation is to introduce Ha et al.'s (2000a,b) inferential methods for the random effects models via the h-likelihood, which provide a conceptually simple, numerically efficient and reliable inferential procedures.

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