Factors for Cost:Benefit
It was good to see an approach to Cost:Benefit Analysis (CBA) that showed the limits and the benefits of using such a technique ( Analysis,
RAIL 838). What needs to be clear is that CBA is a ranking device showing the relative worth of a basket of projects. It does not (nor cannot) show whether the HS2 project, for example, is worth doing in its own right, in isolation.
Given the role of politics, this may mean that the ‘best’ or highest benefit projects do not always get done first, or possibly at all. This may be currently the case for the full Midland Main Line electrification, for instance.
The value of journey savings - not the value of time per se, which should be left to the philosophers - is now a problem.
Many people use rail journeys to complete office work and other work-related tasks. Reducing the journey time from Manchester to London may generate employment benefits, but these have to be traded against existing users who have to find more time in the rest of their days for their ‘paperwork’, which may be a disbenefit.
This needs to be included to get a truer picture of the net social worth of a project. Paul Brooks-Burke, Chorlton