There are strong links between a person’s failure to engage in social and economic activities and poor mobility options, especially where car ownership is not an option due to cost, age or disability, and public transport is not available. This situation leads to a high risk of socially excluded people and communities.
The G20 Principles for Quality Infrastructure Investment remind us that infrastructure investment should take into account economic, environmental and social, and governance aspects and that infrastructure facilities and services need to be broadly available, accessible, inclusive, and beneficial to all. However, transport cost-benefit analyses (CBAs) currently value small time savings for car drivers but fail to recognise potential social inclusion benefits, even when studies show that the economic benefits from the latter can dwarf the former.
GI Hub’s useful Cost-Benefit Analysis of Bus Transport Projects tool provides a template for governments and project proponents that importantly includes some social aspects: road safety benefits, health benefits from active transport, and in-vehicle crowding reduction benefits. This article highlights research that has developed monetary measures to enable social inclusion benefits to also be included in CBAs of transport projects.
Social exclusion and lack of transport
Social inclusion is defined as the process of improving participation in society to facilitate enhanced opportunities and access to resources for people experiencing disadvantages. The interface between transport and social exclusion has been of interest for about two decades, particularly in the United Kingdom (UK), Europe and Australia. Research has shown how a range of personal, geographic, institutional, and other mobility or accessibility contexts can increase or reduce the likelihood of social exclusion. The importance of trip making to reduce the risk of social exclusion has been demonstrated by Stanley et al. in research here and here. Transport infrastructure that increases trip making for those experiencing disadvantage leads to more inclusive societies.
Research undertaken by Stanley in 2021 and in the work cited above has focused on monetisation of social inclusion benefits using econometric techniques, enabling imputation of values for added trips by those at risk of mobility-related social exclusion. It found that, for households with a mean sample household income, an additional trip was worth around AUD25, but higher for those on a low-income and lower for high-incomes. This is a very significant value as, to put this into perspective, the average value for private time savings used in cost-benefit assessment in Australia is around AUD18 per hour.
The high value of a trip for socially excluded people
In the econometric modelling work, risk of social exclusion was the dependent variable. Building on previous work, a person’s risk of social exclusion was assessed against five indicators relating to:
- income
- employment
- political activity
- social support
- participation.
Explanatory variables included subjective wellbeing, bridging and bonding social capital, sense of community, trips (being indicative of involvement in activities, suggestive of inclusion), household income, and if a person was aged between 15-17 years. Detailed household surveys and trip diaries provided the source data, with over 1000 respondents across Melbourne and regional Victoria, Australia.
Using the trip value derived from that work, 2011 research estimated that the largest single benefit from Melbourne’s route bus services was the social inclusion value. This social inclusion trip value was used in a 2021 project appraisal by KPMG for the Victorian Government’s Suburban Rail Loop through middle Melbourne, the largest infrastructure project ever proposed in Victoria.
Transport economists typically value additional trips, following a new transport initiative, at half the value per trip that is ascribed to pre-existing (base) trips. The value for additional trips estimated by Stanley et al. is about three times that value (see research cited above). However, the ‘rule-of-a-half’ is essentially concerned with summing marginal changes for large numbers of trips (e.g. saving 30 seconds of travel time on a trip). Research undertaken by Stanley et al. suggest that additional trips to those at risk of exclusion are essentially non-marginal changes which support inclusion.
New research on reducing societal costs of exclusion
Recent work on valuing trips that reduce exclusion risk suggests a second likely contributor to the high value of additional trip making. Social exclusion creates costs for both the excluded person and for the wider community in terms of unemployment, poor health, crime etc, with consequential direct welfare and health costs as well as costs borne by the wider society. There is thus another important class of benefit potentially available from enabling those who are at risk of mobility-related social exclusion to engage more fully in society: what we call social exclusion externality benefits (Stanley et al. under review).
Wide applicability of social inclusion in cost-benefit appraisal
Derivation of the values for additional trip making by those at mobility-related exclusion risk drew on a bespoke survey for its data collection but can be applied more widely with simplifying assumptions, that do not depend on such survey data. We believe that the findings are relevant to other spatial and economic contexts that are similar to those in Australia, and we encourage others to test out application possibilities.
Mainstreaming those estimates into assessments – even as complementary indicators - would certainly advance the consideration of social outcomes in transport and infrastructure appraisals and decisionmaking. Those who are at risk of mobility-related social exclusion could do with the support.
Cost Benefit Analysis of Bus Transport Projects
