• 한국도로학회논문집
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• 제20권2호
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• pp.67-74
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• 2018

PURPOSES : The goal of this study is the development of roundabout accident models for urban and non-urban areas. METHODS : This study performed a comparative analysis of the regional factors affecting accidents. Traffic accident data were collected for the period 2010~2014 from the TAAS data set of the Road Traffic Authority. To develop the roundabout accident models, the Poisson and negative binomial regression models were used. A total of 25 explanatory variables such as geometry, and traffic volume were used. RESULTS : The key findings are as follows: First, it was found that the null hypotheses that the number of accidents is the same should be rejected. Second, three Poisson regression accident models, which are statistically significant (${\rho}^2$ of 0.154 and 0.385) were developed. Third, it was noted that although the common variable of the three models (models I~III) is the number of entry lanes, the specific variables are entry lane width, roundabout sign, number of circulatory roadways, splitter island, number of exit lanes, exit lane width, number of approach roads, and truck apron. CONCLUSIONS : The results of this study can provide suggestive countermeasures for decreasing the number of roundabout accidents.

• 한국안전학회지
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• 제26권5호
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• pp.130-135
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• 2011

This study deals with the accident models of arterial road sections. The objectives is to develop the models by number of lane. In pursuing the above, this study gives particular emphasis to dividing the 474 small link sections, collecting the accident data of 2007, and applying the statistical programs of SPSS17.0 and NLOGIT4.0. The main results are as follows. First, the number of accidents of two-lane roads were analyzed to be 59.9% of totals and to be the most of all. Second, one Poisson and two negative binomial regression models which were all statistically significant were developed. Finally, the common variables of all models were evaluated to be ADT and number of exit/entry which were all positive to the accidents.

• 한국안전학회지
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• 제27권2호
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• pp.105-110
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• 2012

This study deals with the accident models of rotary. The objectives is to develop the models by day and nighttime. In pursuing the above, this study gives particular attentions to collecting the data of geometric structure and accidents of 20 rotaries and developing the Poisson and negative binomial regression models using NLOGIT 4.0. The main results are as follows. First, the numbers of accident of nighttime (1.03 per 1,000 entering vehicles) were analyzed to be very higher than those of day (0.47 per 1,000 entering vehicles). Second, 4 Poisson models which were all statistically significant were developed, in which the dependent variable were both the number of accident and EPDO (equivalent property damage only). Finally, the number of entry/exit ($X_1$) and the number of entering lane ($X_5$) in the models of the number of accident, and $X_1$ in the EPDO models were adopted as the common variables. The variables were analyzed to be all positive to the dependent variables.

• 수산경영론집
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• 제38권2호
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• pp.79-101
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• 2007

The purpose of this study is to estimate the economic value of the Songieong Beach in Off-season, using a Individual Travel Cost Model(ITCM). Songieong Beach is located in Busan but far away from city. These days, however, the increased rate of traffic inflow to the Songieong beach and the five-day working week are reflected in the trend analysis. Moreover, people have changed psychological value. For that reason, visitors are on the increase on the beach in off-season. The ITCM is applied to estimate non-market value or environmental Good like a Contingent Valuation Method and Hedonic Price Model etc. The ITCM was derived from the Count Data Model(i.e. Poisson and Negative Binomial model). So this paper compares Poisson and negative binomial count data models to measure the tourism demands. The data for the study were collected from the Songjeong Beach on visitors over the a week from November 1 through November 23, 2006. Interviewers were instructed to interview only individuals. So the sample was taken in 113. A dependent variable that is defined on the non-negative integers and subject to sampling truncation is the result of a truncated count data process. This paper analyzes the effects of determinants on visitors' demand for exhibition using a class of maximum-likelihood regression estimators for count data from truncated samples, The count data and truncated models are used primarily to explain non-negative integer and truncation properties of tourist trips as suggested by the economic valuation literature. The results suggest that the truncated negative binomial model is improved overdispersion problem and more preferred than the other models in the study. This paper is not the same as the others. One thing is that Estimating Value of the Beach in off-season. The other thing is this study emphasizes in particular 'travel cost' that is not only monetary cost but also including opportunity cost of 'travel time'. According to the truncated negative binomial model, estimates the Consumer Surplus(CS) values per trip of about 199,754 Korean won and the total economic value was estimated to be 1,288,680 Korean won.

• 한국도로학회논문집
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• 제12권2호
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• pp.43-49
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• 2010

본 연구는 청주시의 가로구간 교통사고를 다루고 있다. 연구의 목적은 가로구간의 사고모형을 개발하는 데 있다. 이를 위해서 이 연구에서는 전체 322개 세부구간으로 분리된 간선도로의 사고 자료를 이용하여 ZAM 모형을 개발하는데 중점을 두고 있다. ZAM 모형의 일종인 ZIP(zero inflated Poisson model)과 ZINB(zero inflated negative binomial model)를 중심으로 분석한 연구의 주요결과는 다음과 같다. 첫째, 모형의 적합성을 결정하는 Vuong 통계 값과 과분산계수 ${\alpha}$의 t 통계 값을 바탕으로 개발된 다양한 모형을 평가한 결과, 포아송, 음이항, ZIP 및 ZINB 회귀모형 중 ZINB 모형이 최적인 것으로 나타난다. 둘째, ZINB 모형은 t, ${\rho}$ 및 ${\rho}^2$값 (0.63)의 관점에서 보면, 다른 모형에 비해서 통계적으로 매우 의미 있는 모형으로 평가된다. 마지막으로, 개발된 ZINB 모형의 사고 요인은 교통량, 진출입구 수 그리고 중앙분리대 길이로 분석된다. 교통량과 진출입구 수는 사고발생에 '+'요인, 그리고 중앙분리대 길이는 '-'요인으로 평가된다.

• 한국안전학회지
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• 제29권5호
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• pp.154-159
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• 2014

This study deals with the pedestrian accidents of intersections in case of Cheongju. The objective is to develop the pedestrian accident models using Tobit regression model. In pursuing the above, the pedestrian accident data from 2007 to 2011 were collected from TAAS data set of Road Traffic Authority. To analyze the accident, Poisson, negative binomial and Tobit regression models were utilized in this study. The dependent variable were the number of accident by intersection. Independent variables are traffic volume, intersection geometric structure and the transportation facility. The main results were as follows. First, Tobit model was judged to be more appropriate model than other models. Also, these models were analyzed to be statistically significant. Second, such the main variables related to accidents as traffic volume, pedestrian volume, number of traffic island, crossing length and the pedestrian countdown signal systems were adopted in the above model.

• 응용통계연구
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• 제21권4호
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• pp.603-613
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• 2008

셀 수 있는 이산 자료 중에서 일반적인 모형에 비하여 영의 빈도가 과도하게 많이 관측되는 자료가 있다. 이러한 경우에 포아송 또는 음이항회귀모형과 같은 일반적인 회귀모형에 의한 분석은 적절하지 못하다. 본 논문에서는 영과잉 포아송회귀모형과 영과잉 음이항회귀모형에 대하여 베이지안 분석을 하였다. 또한, 마코브 연쇄 몬테카롤로 방법으로 계산한 베이즈 요인을 이용하여 모형선택을 하였다. 실제 교통사고 자료를 분석하여 이론적인 결과들을 뒷받침하였다.

• 한국도로학회논문집
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• 제14권6호
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• pp.103-110
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• 2012

PURPOSES : In Korea, over 70 percent of the land consists of mountainous and rolling area. Thus, tunnels continue its upward trend as road network are extended. In these circumstances, the importance of tunnel has been increased nowadays and then its safety investigation and research should be performed. This study is focus on confirming and improving the safety of tunnel. On tunnel hood, sunglare effect can irritate driver's behavior instantly and this can result in incident. METHODS : The study of this phenomenon is rarely conducted in domestic and foreign papers, so there is no proper measure for this. This study analyzes the driving environment of the effect of sunglare effect on tunnel hood. RESULTS : Traffic accidents stem from complex set of factors. This study build the Traffic Accident Prediction Models to find out the effect of sunglare effect on tunnel's hood. The independent variables are traffic volume, geometric design of road, length of tunnel and road side environment. Using these variables, this model estimates accident frequency on tunnel hood by Poisson regression model and Negative binomial regression model. Although Poisson regression model have more proper goodness of fit than Negative binomial regression model, Poisson regression model has overdipersion problem. So the Negative binomial regression model is used in this analysis. CONCLUSIONS : Consequently, the model shows that sunglare effect can play a role in driving safety on tunnel hood. As a result, the information of sunglare effect should be noticed ahead of tunnel hood so this can prevent drivers from being in hazard situation.

• 한국안전학회지
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• 제24권2호
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• pp.94-99
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• 2009

This study deals with the traffic accidents at the 3-legged signalized intersections in Cheongu. The goals are to analyze the geometric, traffic and operational conditions of intersections and to develop a various functional forms that predict the accidents. The models are developed through the correlation analysis, the multiple linear, the multiple nonlinear, Poisson and negative binomial regression analysis. In this study, two multiple linear, two multiple nonlinear and two negative binomial regression models were calibrated. These models were all analyzed to be statistically significant. All the models include 2 common variables(traffic volume and lane width) and model-specific variables. These variables are, therefore, evaluated to be critical to the accident reduction of Cheongju.

• Journal of the Korean Data and Information Science Society
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• 제28권5호
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• pp.1087-1097
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• 2017

본 연구는 계수자료 (count data)를 반응변수로 갖는 포아송회귀 모형, 음이항회귀 모형, 영과잉 포아송회귀 모형, 영과잉 음이항회귀 모형의 4 모형의 비교를 통해 보험 설계사들의 이직횟수 적합을 위한 최적모형을 찾고자 한다. 보험설계사 이직횟수의 분산이 평균보다 큰 과대산포가 존재하고 0인 경우의 비중이 높을 경우에 영과잉 음이항회귀 모형을 적합하는 것이 타당함을 보여주고 보험 설계사들의 이직횟수에 영향을 주는 요인을 규명하고자 한다. 로그우도값, AIC, SBC 등을 고려하여 보험설계사 이직횟수 적합을 최적의 모형은 영과잉 이항모형과 음이항회귀모형의 결합인 영과잉 음이항 모형이 선택되었다. 영과잉 이항모형에 포함된 변수로는 성별, 총 보험설계사 근무연월, 교차모집 설계사 등록, 보유고객 수, 소속회사 유형이었고, 음이항회귀 모형에 포함된 변수로는 직무만족, 조직몰입, 채널경영만족, 총 보험설계사 근무연월, 현 직장에서 근무연월, 소속회사 유형이었다. 영과잉 음이항회귀 모형의 적합결과, 이직횟수에 유의한 영향을 주는 요인으로는 현 직장에서 근무연월, 총 보험설계사 근무연월, 소속회사 유형, 채널경영만족, 직무만족 순으로 나타났다.