• Title/Summary/Keyword: Variable importance

Search Result 806, Processing Time 0.041 seconds

Hierarchically penalized support vector machine for the classication of imbalanced data with grouped variables (그룹변수를 포함하는 불균형 자료의 분류분석을 위한 서포트 벡터 머신)

  • Kim, Eunkyung;Jhun, Myoungshic;Bang, Sungwan
    • The Korean Journal of Applied Statistics
    • /
    • v.29 no.5
    • /
    • pp.961-975
    • /
    • 2016
  • The hierarchically penalized support vector machine (H-SVM) has been developed to perform simultaneous classification and input variable selection when input variables are naturally grouped or generated by factors. However, the H-SVM may suffer from estimation inefficiency because it applies the same amount of shrinkage to each variable without assessing its relative importance. In addition, when analyzing imbalanced data with uneven class sizes, the classification accuracy of the H-SVM may drop significantly in predicting minority class because its classifiers are undesirably biased toward the majority class. To remedy such problems, we propose the weighted adaptive H-SVM (WAH-SVM) method, which uses a adaptive tuning parameters to improve the performance of variable selection and the weights to differentiate the misclassification of data points between classes. Numerical results are presented to demonstrate the competitive performance of the proposed WAH-SVM over existing SVM methods.

Acculturative Stress and Marital Adjustment among Marriage Migration Females: Focusing on the Mediating and Moderating Effects of Ego-Resilience (결혼이주여성의 문화적응스트레스와 부부 적응: 자아탄력성의 매개효과 및 조절효과를 중심으로)

  • Kim, Hyun-Suk;Kim, Hee-Jae;Choi, Song-Sik
    • Journal of Family Resource Management and Policy Review
    • /
    • v.14 no.2
    • /
    • pp.153-176
    • /
    • 2010
  • The purpose of this study was to investigate the relationship between marriage migration females' acculturative stress and marital adjustment, especially the mediating and moderating effects of ego-resilience. The structural equation models were tested by setting marriage migration females' acculturative stress as a prediction variable, their marital adjustment as an outcome variable and their ego-resilience as mediator and moderator variables. The sample consisted of 172 marriage migration females from Busan. I analyzed the data using correlation analysis in order to discover the correlation coefficient of those variables among acculturative stress, ego-resilience and marital adjustment. I used the structural equation model (SEM) for investigating the relationship among acculturative stress, ego-resilience and marital adjustment and for investigating the mediating effects of ego-resilience. I also used multiple group analysis and two way ANOVA to investigate the moderating effects of ego-resilience. The results of structural equation modeling were as follows: first, it was proved that ego-resilience was exerted as a mediating variable, because acculturative stress appeared to affect marital adjustment in relation to ego-resilience. Therefore, marital adjustment was evident when ego-resilience was low. Second, it was proved that ego-resilience was exerted as a moderating variable, because those with low ego-resilience experienced high acculturative stress and low marital adjustment, and those with high ego-resilience experienced low acculturative stress and high marital adjustment. Such findings point out the importance of considering personal characteristics, like ego-resilience, in the relationship between acculturative stress and marital adjustment.

  • PDF

Estimation of lapse rate of variable annuities by using Cox proportional hazard model (Cox 비례위험모형을 이용한 변액연금 해지율의 추정)

  • Kim, Yumi;Lee, Hangsuck
    • Journal of the Korean Data and Information Science Society
    • /
    • v.24 no.4
    • /
    • pp.723-736
    • /
    • 2013
  • The importance of lapse rate is highly increasing due to the introduction of Cash Flow Pricing system, non-refund-of-reserve insurance policy, and IFRS (International Financial Reporting System) to the Korean insurance market. Researches on lapse rate have mainly focused on simple data analysis and regression analysis, etc. However, lapse rate can be analyzed by survival analysis and can be well explained in terms of several covariates with Cox proportional hazard model. Guaranteed minimum benefits embedded in variable annuities require more elegant statistical analysis of lapse rate. Hence, this paper analyzes data of policyholders with variable annuities by using Cox proportional hazard model. The key variables of policy holder that influences the lapse rate are payment method, premium, lapse insured to term insured, reserve-GMXB ratio, and age.

Effects of Illumination on Satisfaction of Night Use at Urban Neighborhood Park (조명이 도시근린공원의 야간이용만족도에 미치는 영향)

  • 최연철;김진선
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.29 no.1
    • /
    • pp.92-99
    • /
    • 2001
  • This study analyzed the effects of illumination on psychological accessibility from a view of satisfaction of night use at urban neighborhood park for actual night users. For this, we have classified the effects of illumination as five sampled independent variables from 12 effects of illumination, and tested the relationship with satisfaction of night use of a dependent variable by multiple regression analysis. The results of this study are as follows; 1) The effects of illumination for night use at urban neighborhood park were divided into five factors; (1) direct effect, (2) effect of promoting use, (3) effect of ensuring security, (4) effect of preparing landscape in the night time, and (5) psychological effect. Among independent variables indicating characteristics of effects of each illumination, uneasiness at night use was high. 2) In a multiple regression model, when other conditions were not changed, the value of security of night use (X\ulcorner) had maximumly an affect on the value of dependent. And, the value of danger to meet the depraved(X\ulcorner) had minimally an affect on the value of dependent variable. 3) For the contribution of security of nigh use(X\ulcorner) and brightness of present using space(X$_4$) to satisfaction of night use(Y) of dependent variable, they had a nearly equal effect on that, and showed about 2 times importance compared to familiarity with park(X\ulcorner) and the beauty of park(X\ulcorner). Also, they showed about 7 times contribution to satisfaction of night use compared to danger to meet the depraved(X\ulcorner), which had minimally an affect on the value of dependent variable, as the most important variables. 4) For the effects of illumination on satisfaction of night use, the effect of ensuring security - pursues security of park for the general rather than security for the specific class or subject - and direct effect to offer proper brightness in using space relatively affected on it much compared to psychological effect, effect of preparing landscape in night time, and effect of promoting use. A research on the psychological effects among the variables related to illumination as well as physical circumstances such as the height, location, direction of illumination should be studied.

  • PDF

Needs for clinical dietitian in hospital settings: Importance of doctor's awareness regarding clinical nutrition service as mediating variable (의료기관 임상영양사 요구도에 미치는 영향 : 임상영양서비스의 중요도에 대한 의사의 인식을 매개역할 중심으로)

  • Um, Mi Hyang;Park, Yoo Kyoung;Song, Yoon Mi;Lee, Song Mi;Lyu, Eun Soon
    • Journal of Nutrition and Health
    • /
    • v.50 no.5
    • /
    • pp.519-529
    • /
    • 2017
  • Purpose: The purpose of this study was to explore whether or not there is a relationship between doctor's awareness of clinical nutrition service and needs for a clinical dietitian. Methods: A cross-sectional survey design was used. The research was carried out by using questionnaires that had been specifically designed for the study. The research was conducted from September to October, 2013 for 311 doctors at 43 hospitals (with over 400 beds). Frequency analysis, factor analysis, reliability analysis, confirmatory factor analysis, and bootstrapping analysis were conducted using SPSS 21.0. Results: 'Implementation of clinical nutritional service' (p < 0.001) and 'usefulness on clinical nutrition service' (p < 0.001) were found to be correlated with 'importance of clinical nutrition service' as an independent variable. The correlation between 'importance of clinical nutrition service' as a mediating variable and 'needs for clinical dietitian' as a dependent variable was also confirmed (p < 0.001). The results of the bootstrapping test showed that the mediating effect of 'importance of clinical nutrition service' was significant. The indirect effect value between 'implementation of clinical nutrition service' and 'needs for clinical dietitian' was 0.040, indirect effect value between 'usefulness on clinical nutrition service' and 'needs for clinical dietitian' was 0.095. Conclusion: The frequency of providing clinical nutritional services, the quality of clinical nutritional services, and the degree of implementation of clinical nutritional services were found to be important for positive perception of clinical nutrition services by doctors. Therefore, proper provision of clinical nutrition services and effective therapeutic effects will be continuously highlighted, which will increase the awareness of the physician and ultimately increase the demand for clinical nutrition service.

A Study on the Commodity Substitution of Housework (가사노동의 상품대체에 관한 연구)

  • 이기영
    • Journal of Families and Better Life
    • /
    • v.5 no.2
    • /
    • pp.45-64
    • /
    • 1987
  • In this study the phenomenon of commodity substitution of housework is approach in the contexts of economic system, patriachal family system and housework-related human resources. the objectives of this study are as follows: (1) To measure the level of commodity substitution of housework in large cities. (2)To investigate the factors influencing commodity substitution of housework. The samples were composed of 982 housewives dwelling in 6 large cities including Seoul. The statistics used for data analysis were frequency distribution, percetile. multiple regression analysis. The major findings are the following; (1) When the housework was divided into two subdomains , in the domain of food the purchase level was for below average while in the domain of clothes, the level was quite higher than average. This result hows that commodity substitution has become more common in the domain of clothes by mass production of clothes on a commercial scale. (2) the level of commodity substitution of housework was influenced by the family attribute variables such as housewife's age, family income. housewife's education, family types, housewife's brought-up regions, presence of sewing machine, employment status of housewife, by one patriarchal norm variable such as home-orientedness, and by tow human resource variables such as importance of housework and household tasks performance competnecy. Among variables house wife's age was the most influential one and such variables as family income, housewife's education, household task performance competency, importance of housework, and home-orientedness were also important. Considering that the influence of home-orientedness demonstrates the importance of patriarchy and that importance of housework and that performance competency also are determined by the patriarchal variables such as sex-role attitude and home-orientedness, we can conclude that Hartmann's theoretical approach with which the changes of housework were explained in the two contexts of economic system and family system is applied to the changes of housework in Korea.

  • PDF

Improvement of VMS Traffic-information Contents Using Importance Preference Analysis (IPA분석을 통한 VMS 제공 교통정보 콘텐츠 개선방안)

  • Park, Bum-Jin;Moon, Byeong-Sup
    • The Journal of the Korea Contents Association
    • /
    • v.11 no.10
    • /
    • pp.457-466
    • /
    • 2011
  • In general, drivers need a self-interest information to decide their routes. So, non-governmental sectors, such as Internet Portal Company, make and provide user-oriented contents for drivers in a hurry. But, VMS which is the typical public media always provides traffic-information for drivers without weighting personal characteristics and considering transportation conditions. So in this research, we searched importance and preference of traffic-information contents as IPA(Importance-Performance Analysis)result. We can draw the conclusion that the improvement of traffic-information contents focused on users(drivers) is needed. Specially, we proposed the strategy of VMS according to traffic conditions.

A Study on the Intention and Behavior of Sharing Information in Online World: Focusing on Moderating Effect of Information Importance (온라인상에서 정보공유 의도 및 행동에 미치는 영향에 관한 연구 - 정보 중요성의 조절효과를 중심으로 -)

  • Kim, Gu
    • Informatization Policy
    • /
    • v.20 no.1
    • /
    • pp.22-41
    • /
    • 2013
  • The purpose of this paper is to examine the effect of interpersonal face-to-face offline on identification-based trust and reciprocity norm in online world, and the effect of identification-based trust and reciprocity norm on the intention and behavior of sharing information in online world. To understand the moderating role, the importance of information was established as a moderating variable, and an empirical analysis was conducted, focusing on the undergraduate. The results of this study are as follows. It was found that interpersonal face-to-face in offline world affects identification-based trust and reciprocity norm in online positively. A reciprocity norm of identification-based trust and reciprocity norm in online world affected by interpersonal face-to-face in offline world has a positive effect on the intention and behavior of sharing information in online, but showed that identification-based trust does not affect them significantly. And reciprocity norm has significant relationship with information sharing behavior through the intention to share information. It was found to be a partial moderating effect of importance of information on the relationship among the reciprocity norm and the intention and behavior of sharing information.

  • PDF

Analysis of the Feature Importance of Occupational Accidents Occurring at Construction Sites on the Severity of Lost Workdays (건설 현장에서 발생한 업무상 재해가 근로손실일수 심각도에 미치는 특징 중요도 분석)

  • Kang, Kyung-Su;Choi, Jae-Hyun;Ryu, Han-Guk
    • Journal of the Korea Institute of Building Construction
    • /
    • v.21 no.2
    • /
    • pp.165-174
    • /
    • 2021
  • The construction industry causes the most accidents and fatalities among all industries. Although many efforts have been made to reduce safety accidents in construction, the study on the lost workdays that return to work place is insufficient. Therefore, this study proposes a model that classifies the lost workdays lost into moderate and severity, and derives the importance of variable and analyzes important factors through the trained random forest model. We analyze the learning process of the random forest which is a black box model, and extracted important variables that impact on the severity of the lost workdays through the extracted feature importance. The factors existing inside were analyzed through the extracted variables. The purpose of this study is to analyze the accident case data at the construction site through a random forest model and to review variables that have a high impact on the lost workdays. In the future, this sutdy can apply to improve construction safety management and reduce the accident of industrial accidents.

A Study on the Consumers' Inherent Characteristics Influencing on the Relationship Building Intention with the Salesperson: Relational Benefits as Mediating Variables (영업사원과의 관계구축 의도에 영향을 미치는 소비자의 내재적 특성에 관한 연구: 관계적 혜택을 매개변수로)

  • Park, Chanwook
    • Asia Marketing Journal
    • /
    • v.11 no.3
    • /
    • pp.31-56
    • /
    • 2009
  • As the competition intensifies and the market matures, marketers are more and more concerned with the relationship marketing. Many of the previous researches have pointed out that not all of the consumers are relationship-oriented. But none of the previous research has systematically investigated this issue. This research investigated the relationship among the three concepts: consumers' intrinsic characteristics, perceived importance of relational benefits, and relationship building intention with the salesperson. In this research the perceived importance of relational benefits is treated as mediating variable in the relationship between consumers' intrinsic characteristics and relationship building intention with the salesperson. The conceptual model in this study can be depicted as follows. From the consumers' perspective relational benefits can be defined as "the additional benefits consumers can receive in addition to core services through the long-term relationship with the service provider." And in this study two kinds of relational benefits are adopted by reviewing the previous research: confidence benefits and social benefits. Relational benefit received from the salesperson is very important to predict consumers' relationship building intention with the salesperson. The more relational benefits consumer wants from the salesperson, the more relationship building intention he/she has. From this point two hypotheses are derived as follows. Hypothesis 1: As the perceived importance of confidence benefit from the salesperson increases, the relationship building intention with the salesperson increases. Hypothesis 2: As the perceived importance of social benefit from the salesperson increases, the relationship building intention with the salesperson increases. In this study four individual characteristics(risk taking tendency, variety-seeking tendency, product knowledge, trust orientation) are hypothesized to influence the perceived importance of confidence benefits from the salesperson. And three individual characteristics(interpersonal orientation, price consciousness, trust orientation) are hypothesized to influence the perceived importance of social benefits from the salesperson. These 7 hypotheses are as follows. Hypothesis 3: As the risk taking tendency increases, the perceived importance of confidence benefits from the salesperson decreases. Hypothesis 4: As the variety-seeking tendency increases, the perceived importance of confidence benefits from the salesperson decreases. Hypothesis 5: As the product knowledge increases, the perceived importance of confidence benefits from the salesperson decreases. Hypothesis 6: As the trust orientation increases, the perceived importance of confidence benefits from the salesperson increases. Hypothesis 7: As the interpersonal orientation increases, the perceived importance of social benefits from the salesperson increases. Hypothesis 8: As the price consciousness increases, the perceived importance of social benefits from the salesperson decreases. Hypothesis 9: As the trust orientation increases, the perceived importance of social benefits from the salesperson increases. The whole model in this study can be depicted as follows: Data were collected from the 396 consumers who actually trade stocks through the salesperson and were analyzed using structural equation model. The analysis results show that consumers' perceived importance of relational benefits(confidence benefit and social benefit) play the roles of mediating variables in the causal relationship between consumers' inherent characteristics and their relationship building intention with the salesperson. As for the individual characteristics, the influences of variety-seeking tendency, trust orientation, and price consciousness are statistically significant. It was found that variety-seeking tendency has a significant negative effect on the perceived importance of confidence benefit, and that trust orientation has a significant positive effect on the perceived importance of both of confidence and social benefit. Finally it was also found that, on the contrary to the influence direction suggested in the hypothesis, price consciousness has a significant positive effect on the perceived importance of social benefit.

  • PDF