Development of crash modification factors for changing lane width on roadway segments using generalized nonlinear models.

摘要: This study evaluates the effectiveness of changing lane width in reducing crashes on roadway segments. To consider nonlinear relationships between crash rate and width, develops generalized models (GNMs) using 3-years records road geometry data collected for all segments Florida. The also estimates various modification factors (CMFs) different ranges based results GNMs. It was found that highest 12-ft lower less than or greater 12 ft. GNMs can extrapolate this continuous effect estimate CMFs any not only selected widths, unlike linear (GLMs) with categorical variables. estimated reflect are likely to occur narrower lanes if is ft whereas wider However, these effects varied posted speed limits as interaction limit significant. show widths higher equal 40 mph. from at severity levels (KABC KAB) compared lane. demonstrates clearly variations which cannot be captured by GLMs. Thus, it recommended relationship nonlinear,