• Title/Summary/Keyword: ordered probit

Search Result 91, Processing Time 0.027 seconds

Estimating Utility Function of In-Vehicle Traffic Safety Information Incorporating Driver's Short-Term Memory (운전자 단기기억 특성을 고려한 차내 교통안전정보의 효용함수 추정)

  • Kim, Won-Cheol;Fujiwara, Akimasa;Lee, Su-Beom
    • Journal of Korean Society of Transportation
    • /
    • v.27 no.4
    • /
    • pp.127-135
    • /
    • 2009
  • Most traffic information that drivers receive while driving are stored in their short-term memory and disappear within a few seconds. Contemporary modeling approaches using a dummy variable can't fully explain this phenomenon. As such, this study proposes to use utility functions of real-time in-vehicle traffic safety information (IVTSI), analyzing its safety impacts based on empirical data from an on-site driving experiment at signalized intersection approach with a limited visibility. For this, a driving stability evaluation model is developed based on driver's driving speed choice, applying an ordered probit model. To estimate the specified utility functions, the model simultaneously accounts for various factors, such as traffic operation, geometry, road environment, and driver's characteristics. The results show three significant facts. First, a normal density function (exponential function) is appropriate to explain the utility of IVTSI proposed under study over time. Second, the IVTSI remains in driver's short-term memory for up to nearly 22 second after provision, decreasing over time. Three, IVTSI provision appears more important than the geometry factor but less than the traffic operation factor.

Development of Severity Model for Rural Unsignalized Intersection Crashes (지방부 비신호 교차로 교통사고 심각도 예측모형 개발 - 수도권 주변 및 전라북도 지역의 3지 비신호 교차로를 중심으로 -)

  • Lee, Dong-Min;Kim, Eung-Cheol;Sung, Nak-Moon;Kim, Do-Hoon
    • International Journal of Highway Engineering
    • /
    • v.10 no.3
    • /
    • pp.47-56
    • /
    • 2008
  • Generally, accident exposure at intersections is relatively higher than that at roadway segments due to more possibility of merging, diverging, turning, crossing, and weaving maneuver. Furthermore, the traffic accident rate at intersections has been rapidly increasing since 1990's. Since there is more opportunity of conflict at unsignalized intersection, frequency and severity of traffic accident are more severe than signalized intersections. The purpose of the study is to analyze factors causing vehicle crashes and provide intersection design guidelines to improve intersection safety. For this study, vehicle to vehicle crash data of 116 rural 3 legs unsignalized were collected and field surveys were conducted for traffic and geometric conditions. Ordered probit models were developed to analyze the severity of crashes. It was found that weather, obstacles in minor roadsides, presence of major exclusive right lane, presence of major road crosswalk, difference between posted speed of major road and minor road, land-use around intersections, shoulder width of major road, ADT of major road are significant factors for intersection safety.

  • PDF

Characteristics and Severity of Side Right-Angle Collisions at Signalized Intersections (신호교차로의 측면직각 층돌사고 특성과 심각도)

  • Park, Jeong-Soon;Park, Gil-Soo;Kim, Tae-Young;Park, Byung-Ho
    • International Journal of Highway Engineering
    • /
    • v.10 no.4
    • /
    • pp.199-211
    • /
    • 2008
  • This study deals with the side right-angle collisions of 4-legged signalized intersections in Cheongju. The goals are to analyze the characteristics of accidents and to find out the accident factors that affect severity using ordered probit model. In pursuing the above, the study uses the data of 580 side right-angle collisions occurred at the 181 intersections(2004-2005). The analyses show that more accidents were occurred in the nighttime and in going straight. The main cause was analyzed to be the red-light violation. Also, the main results of modeling are the following, First, the likelihood ratio index is 0.094 and t-ratio values that explain goodness of fit are significant. Second, minor road traffic volumes, minor road lanes, major road left-turn lanes, major road left-turn signal, major road yellow signal time, cross angle, major and minor road speed limits are significant factors affecting crash severities at signalized intersections.

  • PDF

A Methodology for Driving Risk Evaluation Based on Driving Speed Choice (Focusing on Impacts of Providing In-vehicle Traffic Warning Information) (주행속도선택 기반 주행위험도 평가방법론 개발 (차내 교통안전정보 제공 효과 평가를 중심으로))

  • Kim, Won-Cheol
    • Journal of Korean Society of Transportation
    • /
    • v.29 no.1
    • /
    • pp.95-102
    • /
    • 2011
  • This paper presents a Driving Risk Model (DRM) based on driving speed choices using an Ordered Response Probit (ORP) model. The DRM is conceptualized based on the relation between speed deviation and the occurrence of crashes found by Solomon. The impacts of various driving risk factors are revealed by applying the DRM to evaluate the effectiveness of In-Vehicle Traffic Warning Information (IVTWI) in expressway driving. Regarding driving risk, the results show that: (1) the risk is lower among male drivers, those with more driving experience and those with less accident history, (2) the risk is higher when driving takes place on wet road surface, in the afternoon, and under conditions of low traffic volume, and (3) the risk is also higher on both downgraded and long curve sections. Additionally, the results provide evidence that provision of IVTWI can decrease the driving risk. The proposed DRM provides a solution for assessing the traffic safety impacts of countermeasures on roadways when there is a shortage of traffic accidents data.

Public Attitudes to Saemangeum Development Project and Its Effects on Marine Environment (새만금 개발사업이 해양환경에 미치는 영향에 대한 인식)

  • Baek, Min-Ji;Choi, Hyo-Yeon;Yoo, Seung-Hoon
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.21 no.5
    • /
    • pp.492-500
    • /
    • 2015
  • This paper attempts to analyze the public's attitudes about the Saemangeum development project and its impact on marine environment with the data from a national survey of 1,000 households obtained by a professional survey firm with face-to-face interviews using two split samples: a sample of 400 households in on-site area (Saemangeum area) and a sample of 600 households in off-site area (the nation except for Saemanguem area). More specifically, ordered probit model is employed to investigating the factors affecting the public attitudes to the Saemanguem development project. The results show that over 70 percentage of respondents in both the samples opposed Saemanguem development project when they considered its economic gain and impacts on marine environment at the same time. Futhermore, over 90 percentage of respondents judged that environmental management of Saemanguem open sea is necessary. Therefore, making appropriate actions are required to manage marine environment of Saemanguem open sea.

Identification of Factors Affecting the Crash Severity and Safety Countermeasures Toward Safer Work Zone Traffic Management (공사구간 교통관리특성을 고려한 고속도로 교통사고 심각도 영향요인 분석 및 안전성 증진 방안)

  • YOON, Seok Min;OH, Cheol;PARK, Hyun Jin;CHUNG, Bong Jo
    • Journal of Korean Society of Transportation
    • /
    • v.34 no.4
    • /
    • pp.354-372
    • /
    • 2016
  • This study identified factors affecting the crash severity at freeway work zones. A nice feature of this study was to take into account the characteristics of work zone traffic management in analyzing traffic safety concerns. In addition to crash records, vehicle detection systems (VDS) data and work zone historical data were used for establishing a dataset to be used for statistical analyses based on an ordered probit model. A total of six safety improvement strategies for freeway work zones, including traffic merging method, guidance information provision, speed management, warning information systems, traffic safety facility, and monitoring of effectiveness for countermeasures, were also proposed.

njury Severity Analysis of Cyclists in Two Wheeler to Taxi Crashes: An Application of Vehicle Black Box Data in Incheon, Korea (차량 블랙박스 자료를 활용한 택시-이륜차 사고에서의 이륜차 이용자 사고 심각도 분석)

  • Kim, Seonjung;Chung, Younshik
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.38 no.6
    • /
    • pp.917-923
    • /
    • 2018
  • In recent, technological advancement including a vehicle black box (VBB) has led to reducing such underreporting issues and errors of crash data. The objective of this study is to analyze the injury severity of cyclists on taxi-to-two wheeler crashes based on the accurate crash data collected from the VBB in taxi. This study defined the two wheelers as bicycle and motorcycle. To perform this study, we used the VBB data collected from taxis operating in Incheon, South Korea for a two-year period (2010-2011). An ordered probit model was applied to analyze the injury severity in crashes. As a result, new injury severity factors were found: increase of the crash speed of taxi, damage of crash-involved vehicles (i.e., taxi and/or two wheeler), not standing of cyclists after crash, and second or third impact of cyclists after first crash.

Analysis on the Compliance Factors for the Voluntary Surrender of Driver's License for Senior Drivers (고령운전자 운전면허 자진반납 수용요인 분석)

  • Cheon, Ga-Hyeon;Lee, Chung-Ki;Park, Sang-Soo
    • Asia-Pacific Journal of Business
    • /
    • v.11 no.3
    • /
    • pp.229-242
    • /
    • 2020
  • Purpose - To study the factors that are related with compliance for the voluntary surrender program of drive's license for senior drives and to estimate the rate of voluntary surrender. Design/methodology/approach - We online surveyed 147 individuals in order to analyze the intention to comply the program. The surveyees were driver's license holders aged 54 to 65 and drawn to answer their willingness to comply in a 5-point Likert scale. We developed an ordered probit model to analyze the data. Findings - According to the main results of the empirical analysis, the higher the average number of driving per week, regardless of gender and age, the more negative was the driver toward voluntarily surrender of driver's license. Various policy measures need to be prepared to activate the voluntary surrender system using the willingness to voluntarily surrender the driver's license and the characteristics of the voluntary returners, and the implementation of customized safe driving training for elderly drivers may be one such method. Research implications or originality - Population aging is known to cause various social problems, and in the transportation field, the number of elderly drivers and traffic accidents by elderly drivers are also increasing. The government is implementing a program for elderly drivers to voluntarily surrender of their driver's licenses in order to reduce traffic accidents caused by elderly drivers. If only elderly drivers who rarely drive surrender their driver's licenses then traffic accidents may not reduce as much as the program targets, however, and further policy instruments may be needed.

Analysis of Food Consumption Behavior of Single-person Households in Consideration of Safety Preference (안전성 선호를 고려한 1인가구의 식품소비행태 분석)

  • Kim, Ji-Hoon;Lim, Sung-Soo
    • Korean Journal of Organic Agriculture
    • /
    • v.30 no.1
    • /
    • pp.1-20
    • /
    • 2022
  • With the recent rapid increase in single-person households, food companies are releasing small packaging and small-capacity products regardless of product line such as beverages, fresh foods, and home snacks, and food consumption patterns are also changing. Meanwhile, as a series of accidents related to food safety occurred during cost-effective consumption pursuing price-performance, more consumers wanted to choose products that have been proven safe even with higher money due to food safety anxiety. Considering the concept of 'safety' of food, this study by using the 'ordered probit model' empirically investigated whether there is a difference in the degree of preference for safety in food consumption behavior between single-person and multi-person households. Summarizing the results, it was found that women rather than men, and elderly households among young and single-person households had a higher demand for food safety. The results of marginal effects considering food safety variables show that respondents with low frequency of delivery and take-out use are considering food safety more, and that single-person households are considering safety more than multi-person households. In the future, the population structure of Korea will continue to increase in single-person and elderly households, and women's economic activities will also continue to increase. Therefore, the growing home convenience food market needs marketing strategies to secure and emphasize food safety, such as sterilizing treatment technology for hygiene and safe container development from environmental hormones, and needs a lot of support and attention to meet changes in food culture trends and demographic structure.

내부 및 외부 신호에 의한 미국 EPA의 의사결정

  • Jo, Seung-Guk
    • Environmental and Resource Economics Review
    • /
    • v.7 no.2
    • /
    • pp.87-109
    • /
    • 1998
  • 1989년 미국 환경청(Environmental Protection Agency : EPA)은 유독물질통제법(Toxic Substances Control Act : TSCA)에 의해 석면을 함유하고 있는 일부 제품의 제조, 수업, 가공 및 판매를 세 단계로 나누어 금지하였다. 본 논문은 석면규제를 금지여부결정과 금지우선순위결정으로 구분하여 각 결정에 내재된 EPA의 의사결정요인들을 추론한다. 특히 본 논문은 Magat et al.(1986), Asch and Seneca(1989), Cropper et al.(1992)이 EPA의 의사결정요인들로 제시한 내부신호(internal signals, 비용과 편익의 추정치)와 외부신호(external signals, 외부집단의 참여)를 석면규제에 적용하여 이들의 역할을 고찰한다. 한편 본 논문은 규제에 의해 영향을 받는 이익집단들이 EPA의 의견수렴기간(comment period) 동안에 제출한 의견서(written comments)가 외부신호를 나타낸다고 가정한다. Probit 모형으로 추정된 금지여부결정에 있어 EPA는 TSCA의 규정을 준수하여 비용과 편익을 균형하였고, 기업과 환경보호단체의 참여도 EPA의 의사 결정에 영향을 미쳤다. 즉, 어떤 제품의 금지에 소요되는 비용이 많으면 그 제품이 금지될 확률이 작았고, 그 제품의 금지를 반대하는 기업의 의견서가 많으면 그 제품이 금지될 확률이 작았다. 그러나 외부신호가 포함된 모형에서 내부 신호의 통계적 유의성이 낮아지는 문제가 나타났다. 한편 추정결과는 금지로 인해 감소된 암 한 건에 대한 EPA의 암묵적인(implicit) 평가가 5,000만 달러가 넘는다는 것을 보여 준다. Ordered Probit 모형으로 추정된 금지우선순위결정에 있어, 편익의 단위당 비용이 작을수록, 그리고 그 제품의 금지를 찬성하는 환경보호단체의 의견서가 많을수록 그 제품은 보다 이른 단계에서 금지되었다. 이 경우 외부신호의 계수의 통계적 유의성은 높은 반면 내부신호의 계수의 통계적 유의성은 상대적으로 낮았다.

  • PDF