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                Media ContactsMenu OFFICE OF RESEARCH, DEVELOPMENT, AND TECHNOLOGY AT THE TURNER-FAIRBANK HIGHWAY RESEARCH CENTER Home
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   Ana Maria Eigen
      Ana Maria Eigen
      
                    
            Research Highway Safety Specialist
      
                    
            Office of Safety and Operations Research and Development
      
                    
            Turner-Fairbank Highway Research Center6300 Georgetown PikeMcLean, VA 22101United States
      
          
    **Email:**ana.eigen@dot.gov**Phone:** (202) 493-3168
    If you are deaf, hard of hearing, or have a speech disability, please dial 7-1-1 to access telecommunications relay services.
                
                Journal Citations
    

    
    
    
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Many of the studies conducted using HSIS data result in publication in professional journals, conference proceedings, research records, and other peer-reviewed documents.

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**Safety Effects of Horizontal Curve and Grade Combinations on Rural Two-Lane Highways**

The safety effects of horizontal curves and grades on rural two-lane highways have been quantified in the American Association of State Highway and Transportation Officials (AASHTO) Highway Safety Manual (HSM), but it was not previously known whether and how the safety performance of horizontal curves and grades interact. Furthermore, there are no established safety effects for crest and sag vertical curves, and it is unknown whether and how the safety performance of crest or sag vertical curves is affected by the presence of horizontal curves.

The objective of this study was to quantify the combined safety effects of horizontal curves and grade combinations and express the results as crash modification factors (CMFs) that can be considered for use in the AASHTO HSM.

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**Safety Evaluation of Converting Traffic Signals from Incandescent to Light-Emitting Diodes**

Across the Nation, many agencies have been replacing conventional incandescent light bulbs in traffic signals with light-emitting diodes (LED). LEDs are primarily installed to reduce energy consumption and decrease maintenance. In addition, LEDs are expected to last much longer compared with incandescent bulbs and tend to age gradually. However, a recent study revealed several potential problems with LEDs, including their inability to melt snow and issues related to visual discomfort caused by glare at night.

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**Safety Evaluation Of Discontinuing Late-Night Flash Operations at Signalized Intersections**

During late-night flash (LNF) mode (from late night to early morning hours), traffic signals flash yellow for one road (typically, the major road), requiring caution but no stopping, and flash red for the other road (typically, the minor road), requiring drivers to stop and then proceed through the intersection after yielding to the traffic on the major road. The intent of LNF is to reduce energy consumption and delay during periods of low traffic demand. However, in recent years, many agencies have begun replacing LNF with normal phasing operation because of safety concerns.

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        **2021**
        Title
			Pub Date
			AuthorAnalysis of head-on crash injury severity using a partial proportional odds model
			June
			Pengfei Liu and Wei (David) FanExploring truck driver-injury severity at intersections considering heterogeneity in latent classes: A case study of North Carolina
			June
			Li Song and Wei (David) FanInclusion of speed and weather measures in safety performance functions for rural roadways
			April
			Subasish Das, Srinivas R. Geedipally, and Kay Fitzpatrick
  


      **2020**
        Title
			Pub Date
			AuthorSafety Criteria for Selecting a Smart Corridor: Random Forest Approach Using HSIS Data from Washington State
			December
			Xiaoyu Guo, Yongxin Peng, and Chaolun MaInvestigating Factors That Contribute to Freeway Crash Severity Using Machine Learning
			November
			Amirreza Nickkar, Ali Yazdizadeh, and Young-Jae LeeCollective Risk Ranking of Highway Segments on the Basis of Severity-Weighted Crash Rates
			October
			Dawei Li and Mustafa F.M. Al-MahamdaAnalysis of Single-Vehicle Roadway Departure Crashes on Rural Curved Segments Accounting for Unobserved Heterogeneity
			August
			Mouyid Islam and Anurag PandeA Comparison between Artificial Neural Network and Hybrid Intelligent Genetic Algorithm in Predicting the Severity of Fixed Object Crashes among Elderly Drivers
			April
			Amir Mohammadian Amiri, Anurhossein Sadri, Navid Nadimi, and Moe ShamsOdds of work zone crash occurrence and getting involved in advance warning, transition, and activity areas by injury severity
			April
			Krupanidhi Koilada, Ajinkya S.Mane, and Srinivas S.PulugurthaExploring Injury Severity in Head-On Crashes Using Latent Class Clustering Analysis and Mixed Logit Model: A Case Study of North Carolina
			January
			Pengfei Liu and Wei Fan
  


      **2019**
        Title
			Pub Date
			AuthorA Time of Day Analysis of Pedestrian-Involved Crashes in California: Investigation of Injury Severity, a Logistic Regression and Machine Learning Approach Using HSIS Data
			October
			Seyedmirsjad MokhtarimousaviAge-related differences in motor-vehicle crash severity in California
			August
			Adekunle Adebisi, Jiaqi Ma, Jaqueline Masaki, and John SobanjoComparison of univariate and two-stage approaches for estimating crash frequency by severity—Case study for horizontal curves on two-lane rural roads
			August
			Alireza Jafari Anarkooli, Bhagwant Persaud, Mehdi Hosseinpour, and Taha SaleemImpacts of Work Zone Component Areas on Driver Injury Severity
			August
			Mohamed Osman, Sabyasachee Mishra, Rajesh Paleti, and Mihalis GoliasFactors Influencing Crash Severity at Rural Horizontal Curves in Maine
			May
			Chennan Xue and Dan XuCrash risk factors associated with injury severity of teen drivers
			April
			Venkata Duddu, Venu Madhav Kukkapalli, and Srinivas S. PulugurthaA Multinomial Logit Model of Pedestrian-Vehicle Crash Severity in North Carolina
			March
			Zhen Chen and Wei (David) FanA Longitudinal Analysis of the Effectiveness of California’s Ban on Cellphone Use While Driving
			January
			Chenhui Liu, Chaoru Lu, Shefang Wang, Anuj Sharma, and John ShawFactors Influencing Injury Severity in Alcohol-Related Crashes: A Neural Network Approach Using HSIS Crash Data
			January
			Snehanshu Banerjee and Nashid Khadem
  


      **2018**
        Title
			Publication Date
			AuthorModeling and comparing injury severity of at-fault and not at-fault drivers in crashes
			November
			Venkata R Duddu, Praveena Penmetsa, and Srinivas S PulugurthaA heterogeneity based case-control analysis of motorcyclist’s injury crashes: Evidence from motorcycle crash causation study
			October
			Behram Wali, Asad J. Khattak, and Aemal J. KhattakInjury Severity Analysis of Commercially-Licensed Drivers in Single-Vehicle Crashes: Accounting for Unobserved Heterogeneity and Age Group Differences
			September
			Mohamed Osman, Sabyasachee Mishra, and Rajesh PaletiFactors Influencing Injury Severity of Crashes Involving HAZMAT Trucks
			March
			Majbah Uddin and Nathan HuynhModeling Crash Injury Severity by Road Feature to Improve Safety
			January
			Praveena Penmetsa and Srinivas S Pulugurtha
  


      **2017**
        Title
			Publication Date
			AuthorDevelopment of a global road safety performance function using deep neural networks
			September
			Guangyuan Pan, Liping Fu, and Lalita ThakaliEvaluation of the Impact of Traffic Volume on Site Ranking
			May
			Wen Cheng, Gurdiljot Singh Gill, Luis Loera, Xiaofei Wang, and Jung-Han WangModelling single-vehicle, single-rider motorcycle crash injury severity: an ordinal logistic regression approach
			April
			Mahdi Pour-Rouholamin, Mohammad Jalayer, and Huaguo ZhouInvestigating temporal trends in the explanatory variables related to the severity of drivers' injuries in single-vehicle collisions
			February
			Essam DabbourExamining Injury Severity of Not At-Fault Drivers in Two-Vehicle Crashes
			January
			Praveena Penmetsa, Srinivas S Pulugurtha, and Venkata R Duddud
  


      **2016**
        Title
			Publication Date
			AuthorAnalysis of injury severity of large truck crashes in work zones
			December
			Mohamed Osman, Rajesh Paleti, Sabyasachee Mishra, and Mihalis M Golias
  


      **2014**
        Title
			Publication Date
			AuthorSafety Propensity Index for Signalized and Unsignalized Intersections: Exploration and Assessment
			October
			Justin P. Schorr and Samer H. HamdarComparison of Sichel and Negative Binomial Models in Hotspot Identification
			January
			Lingtao Wu, Yajie Zhao, and Dominique Lord
  


      **2009**
        Title
			Publication Date
			AuthorAppraisal of the Interactive Highway Safety Design Model's Crash Prediction and Design Modules: Case
			February
			Donnell, E.T., F. Gross, B.P. Stodart, and K.S. OpielaSafety Effectiveness of Lane and Shoulder Width Combinations on Rural, Two-Lane, Undivided Roads
			January
			Gross, F., P.P. Jovanis, and K.A. EcclesAnalysis of Effects of Pavement Marking Retroreflectivity on Traffic Crash Frequency on Highways in
			January
			Donnell, E.T., V. Karwa, and S. SathyanarayananSafety Impact of Truck Lane Restrictions on Multilane Freeways
			January
			Fontaine, M.D., C.S. Bhamidipati, and L.E. DougaldAnalysis of Road Crash Frequency with Spatial Models
			January
			Guero-Valverde, J. and P.P. JovanisTwo Low-Cost Safety Concepts for Two-Way, Stop-Controlled Intersections in Rural Areas
			January
			Gross, F., R. Jagannathan, and W. Hughes
  


      **2008**
        Title
			Publication Date
			AuthorAdjustment for Maximum Likelihood Estimate of Negative Binomial Dispersion Parameter
			January
			Park, B. and D. LordEffects of Varying Dispersion Parameter of Poisson-Gamma Models on Estimation of Confidence Interval
			January
			Geedipally, S.R. and D. LordSafety Evaluation of Installing Center Two-Way Left-Turn Lanes on Two-Lane Roads
			January
			Lyon, C., B.N. Persaud, N.X. Lefler, D.L. Carter, and K.A. EcclesSafety Evaluation of Flashing Beacons at Stop-Controlled Intersections
			January
			Srinivasan, R., D.L. Carter, B.N. Persaud, K.A. Eccles, and C. LyonSafety Effectiveness of "Stop Ahead" Pavement Markings
			January
			Gross, F., R. Jagannathan, C. Lyon, and K. EcclesRelationships Between Safety and Both Congestion and Number of Lanes on Urban Freeways
			January
			Kononov, J., B. Bailey, and B.K. Allery
  


      **2007**
        Title
			Publication Date
			AuthorPredicting motor vehicle collisions using Bayesian neural network models: An empirical analysis
			September
			Xie, Y., D. Lord, and Y. ZhangDifficulties with Quasi-Induced Exposure when Speed Varies Systematically by Vehicle Type
			July
			Jiang, X. and R.W. LylesEstimating Safety Benefits of Shoulder Rumble Strips on Two-Lane Rural Highways in Minnesota
			January
			Patel, R., F. Council, and M. GriffithCrash Prediction Models for Intersections on Rural Multilane Highways: Differences by Collision Type
			January
			Jonsson, T., J.N. Ivan, and C. ZhangMultivariate Poisson-Lognormal Models for Jointly Modeling Crash Frequency by Severity
			January
			Park, E.S. and D. LordModeling the Probability of Freeway Rear-End Crash Occurrence
			January
			Kim, J.K., Y. Wang, and G.F. UlfarssonApplication of Innovative Time Series Methodology to Relationship Between Retroreflectivity of Pavement
			January
			Masliah, M., G. Bahar, and E. Hauer
  


      **2006**
        Title
			Publication Date
			AuthorTurning Young Drivers into Survivors
			September
			Opiela, K.S., B.M. Sant,and J.A. ChildersUse of Propensity Score Matching Method and Hybrid Bayesian Method to Estimate Crash Modification Fa
			January
			Davis, G.A. and N. AulPart 5: Surface Transportation Weather: Development of Roadway Weather Severity Index
			January
			Strong, C. and Y. ShvetsovBayesian Multivariate Poisson Regression for Models of Injury Count, by Severity
			January
			Ma, J. and K.M. Kockelman
  


      **2005**
        Title
			Publication Date
			AuthorReal World Crash Evaluation of Vehicle Stability Control (VSC) Technology
			January
			Bahouth, G.Safety Effects of Speed Limit Changes: Use of PanelModels, Including Speed, Use, and Design Variable
			January
			Kockelman, K.M. and Y.J. KweonSafety of U-Turns at Unsignalized Median Openings: Some Research Findings
			January
			Levinson, H.S., I.B. Potts, D.W. Harwood, J. Gluck, and D.J. Torbic
  


      **2004**
        Title
			Publication Date
			AuthorCrash Reduction Following Installation of Centerline Rumble Strips on Rural Two-Lane Roads
			November
			Persaud, B.N., R.A. Retting, and C.A. LyonMethod for Priority-Ranking and Expanding Freeway Service Patrols
			January
			Khattak, A., N. Rouphail, K. Monast, and J. HavelSafety Evaluation of Permanent Raised Snow-Plowable Pavement Markers
			January
			Persaud, B, G. Bahar, C. Mollett, and C. Lyon
  


      **2002**
        Title
			Publication Date
			AuthorEffects of Work Zone Presence on Injury and Non-Injury Crashes
			January
			Asad J. Khattak, Aemal J. Khattak, and Forrest M. Council
  


      **2001**
        Title
			Publication Date
			AuthorThree-Strand Cable Median Barrier in North Carolina: In-Service Evaluation
			January
			W.W. Hunter, J.R. Stewart, K.A. Krull, H.F.Huang, F.M. Council, and D.L.Harkey
  


      **2000**
        Title
			Publication Date
			AuthorExplaining two-lane highway crash rates using land use and hourly exposure
			January
			John N. Ivan, Chunyan Wang, and Nelson R. Bernardo
  


      **1999**
        Title
			Publication Date
			AuthorSafety Effects of the Conversion of Rural Two-Lane to Four-Lane Roadways Based on Cross-Sectional Mo
			October
			Forrest M. Council and J. Richard StewartEffects of Speed Limit Increases on Crash Injury Severity
			October
			Henry Renski, Asad J. Khattak, and Forrest M. CouncilSafety Evaluation of Rolled-In Continuous Shoulder Rumble Strips Installed on Freeways
			October
			Michael GriffithEstimating Truck-Rollover Crashes on Ramps by Using a Multistate Database
			January
			David L. Harkey
  


      **1998**
        Title
			Publication Date
			AuthorInvestigation of National Highway System Roadways in the Highway Safety Information System States
			September
			Charles V. Zegeer, Herman F. Huang, J. Richard Stewart, and Carolyn WilliamsEffects of a Towaway Reporting Threshold on Crash Analysis Results
			September
			Charles V. Zegeer, Herman F. Huang, J. Richard Stewart, Ron Pfefer and Jun WangAccident Models for Two-Lane Rural Segments and Intersections
			September
			Andrew Vogt and Joe BaredApplying the ordered Probit Model to Injury Severity in Truck-Passenger Car Rear-End Collisions
			September
			Chandler S. Duncan, Asad J. Khattak, and Forrest M. CouncilRole of Adverse Weather in Key Crash Types on Limited-Access: Roadways Implications for Advanced Wea
			January
			Khattak, A.J., P. Kantor, and F.M. CouncilSafety Effects of Cross-section Design on Rural Multi-lane Highways
			January
			Jun Wang, Warren E. Hughes, and J. Richard Stewart
  


      **1997**
        Title
			Publication Date
			AuthorEffects of Air Bags on Severity Indices for Roadside Objects
			January
			Forrest M. Council, Yusuf M. Mohamedshah, and J. Richard Stewart
  


      **1996**
        Title
			Publication Date
			AuthorVehicle-Animal Crashes: An Increasing Safety Problem
			August
			Warren E. Hughes, A. Reza Saremi, and Jeffrey F. PaniatiInvestigation of Highway Work Zone Crashes: What We Know and What We Don't Know
			January
			Jun Wang, Warren E. Hughes, Forrest M. Council, and Jeffrey F. Paniati
  


      **1994**
        Title
			Publication Date
			AuthorComparison of the Safety of Lighting Options on Urban Freeways
			
			Michael S. GriffithAccident Rates Using HSIS
			
			Yusuf M. Mohamedshah, and Amy R. KoblsAccident Relationships of Roadway Width on Low-Volume Roads
			January
			Zegeer, C.V., J.R. Stewart, F.M. Council, and T.R. NeumanFrequency and Severity of Crashes Involving Roadside Safety Hardware by Vehicle Type
			January
			John G. Viner, Forrest M. Council, and J. Richard Stewart
  


      **1993**
        Title
			Publication Date
			AuthorModeling Vehicle Accidents and Highway Geometric Design Relationships
			December
			Shaw-Pin Miaou and Harry LumAssociation of Median Width and Highway Accident Rates
			October
			Mathew W. Knuiman, Forrest M. Council, and Donald W. ReinfurtTruck Accident Models for Interstates and Two-Lane Rural Roads
			October
			Yusuf M. Mohamedshah, Jeffrey F. Paniati, and Antoine G. HobeikaStatistical Evaluation of the Effects of Highway Geometric Design on Truck Accident Involvements
			October
			Shaw-Pin Miaou and Harry LumEstimation of Safety at Two-Way stop-Controlled Inrtersections on Rural Highways
			October
			James A. Bonneson and Patrick T. McCoyComparative Performance of Barrier and End Treatment Types Using the Longitudinal Barrier Special St
			January
			Hunter, W.W., J.R. Stewart, and F.M. Council
  


      **1992**
        Title
			Publication Date
			AuthorInvestigation of Passing Accidents Using the HSIS Data Base
			September
			Yusuf M. Mohamedshah
  


      **Publication Date Unknown**
        Title
			Publication Date
			AuthorEvaluation of Truck Crashes Using a GIS-Based Crash Referencing and Analysis System
			
			David L. Harkey

    
          Last updated: Tuesday, July 18, 2023 U.S. DEPARTMENT OF TRANSPORTATION

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