Evaluating the effectiveness of on-road interventions such as as signing and enforcement schemes is sometimes over-simplified. Simply comparing before and after results does not provide an estimation of the effect of trend (change in collision rates elsewhere on the network), or regression to mean (RTM). Allowing for these confounding factors is possible and has been demonstrated in previous studies
. The problem is that it often requires the use of complicated statistical software and trained professionals.
RAPTOR allows road safety professionals to carry out evaluations of schemes and the assessment of hotpots using a web-based tool that is free to access and simple to use. The data requirements are very simple:
Dependent variable: Collision/casualty counts in discrete time periods (e.g. months, quarters or years) for each site
Independent variable(s): Static site data (e.g. speed limit; road type; road class, urban/rural); dynamic site data (e.g. flow; average speeds) for each time period for each time period
Once the data is prepared it can be imported into the system and calculations performed.
Further information about the tool and the statistical methodology by downloading the report below, and support will be available via the RSGB Analysts Network
If you would like to register for access, please fill out the request form which will be sent to the project lead, Dr Neil Thorpe.