The National Academies Press

Currently Skimming:

Pages 15-16

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.

From page 15... ... xvi SUMMARY This report describes efforts to develop improved crash prediction methods for crash type and severity for the three facility types covered in the 2010 Highway Safety Manual (HSM) -- specifically, two‐lane rural highways, multilane rural highways, and urban/suburban arterials. For each, models were estimated for undivided and divided (multilane rural and urban/suburban only) Read the entire page →
From page 16... ... xvii The sample of fatal injury crashes (K) was too small for all facility types to estimate meaningful models. Average proportions must be computed using local jurisdiction data to allocate KA crashes between K and A if a K crash predictive model is needed, provided the count of these crashes is large enough to estimate a proportion reliably. If a count for a specific crash type and level of severity is required, for example single‐vehicle B crashes, the prediction for single‐vehicle KA crashes can be subtracted from the prediction for single‐vehicle KAB crashes to get a prediction for single‐vehicle B crashes. Also revisited was the procedure for calibrating HSM prediction models for application in jurisdictions other than the locations providing the data used to estimate the safety performance functions (SPFs) Read the entire page →

From page 15...

... xvi SUMMARY This report describes efforts to develop improved crash prediction methods for crash type and severity for the three facility types covered in the 2010 Highway Safety Manual (HSM) -- specifically, two‐lane rural highways, multilane rural highways, and urban/suburban arterials. For each, models were estimated for undivided and divided (multilane rural and urban/suburban only)

Read the entire page →

From page 16...

... xvii The sample of fatal injury crashes (K) was too small for all facility types to estimate meaningful models. Average proportions must be computed using local jurisdiction data to allocate KA crashes between K and A if a K crash predictive model is needed, provided the count of these crashes is large enough to estimate a proportion reliably. If a count for a specific crash type and level of severity is required, for example single‐vehicle B crashes, the prediction for single‐vehicle KA crashes can be subtracted from the prediction for single‐vehicle KAB crashes to get a prediction for single‐vehicle B crashes. Also revisited was the procedure for calibrating HSM prediction models for application in jurisdictions other than the locations providing the data used to estimate the safety performance functions (SPFs)

Read the entire page →

Key Terms

← Previous Chapter Skim

Next Chapter Skim →

This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More information on Chapter Skim is available.