Social Decision-Making Analysis: A General Approach to Inform Decisions on Resources in the Public Sector

Public expenditure aims to achieve social objectives by improving a range of socially valuable attributes of benefit (arguments in a social welfare function). Public expenditure is typically allocated to public sector budgets, where budget holders are tasked with meeting a subset of social objectives.

Decision makers require an evidence-based assessment of whether a proposed investment is likely to be worthwhile given existing levels of public expenditure. However, others also require some assessment of whether the overall level and allocation of public expenditure are appropriate. This article proposes a more general theoretical framework for economic evaluation that addresses both these questions.

Using a stylized example of the economic evaluation of a new intervention in a simplified UK context, we show that this more general framework can support decisions beyond the approval or rejection of single projects. It shows that broader considerations about the level and allocation of public expenditure are possible and necessary when evaluating specific investments, which requires evidence of the range of benefits offered by marginal changes in different types of public expenditure and normative choices of how the attributes of benefit gained and forgone are valued.

The proposed framework shows how to assess the value of a proposed investment and whether and how the overall level of public expenditure and its allocation across public sector budgets might be changed. It highlights that cost-benefit analysis and cost-effectiveness analysis can be viewed as special cases of this framework, identifying the weakness with each.