In strategic environmental assessment (SEA), there is increasing interest in examining notions of ‘effectiveness'. There are contested understandings of the term effectiveness (Bond et al. 2013), but many researchers agree that one element is ‘substantive effectiveness' which is related to the outcomes of a policy or plan to which SEA has been applied, i.e. have these outcomes improved because of the assessment? A particular issue is that it is difficult to ascribe impacts to particular policy interventions because of the counterfactuals, that is, other factors influencing the outcome (not directly related to the SEA). This means that it is not possible to demonstrate that any benefits occurred because of the SEA as all the other plans and national policies influence the same outcomes. Counterfactual analysis seeks to calculate the changes that would have occurred without the specific plan implementation and is necessary to demonstrate the value of SEAs (which are seen by some observers as being costly, time-consuming and unnecessary).

Lewis (1973) stated that "Counterfactuals are notoriously vague. That does not mean that we cannot give a clear account of their truth conditions". Thus, an understanding will be required of the nature and types of counterfactual which can influence the same environmental parameters which are targeted by policy interventions. A clear understanding of the existing literature examining policy influence will be needed as a basis for the development of subsequent tools and methods to evaluate the effects of particular plans (see for example, Lenihan and Hart, 2004; Nelson and Mariedia, 2007).

The research will need to develop a typology of counterfactuals based on an extensive literature including work on counterfactual analysis in general, and in relation to environmental impacts specifically, and will form the basis for the development of an approach for counterfactual analysis for interventions subject to SEA at the regional or national scale. The challenge is to review methods for counterfactual analysis and develop a new methodology with potential to finally assess the substantive effect of policy-level SEA. The project is novel because there is no agreed approach for detailing and assessing these counterfactuals.

The project will require extensive literature review, and the ability to apply a grounded theory approach to narrow down the scope of the study and to allow the development (or adaptation) of appropriate methods for counterfactual analysis. It may rely on some survey work for validation of tentative findings. This research approach will help to develop the following skills:

• Literature review and analysis
• Questionnaire survey development and analysis
• Interview techniques
• Theory development

The research will be embedded in the 3S (Science, Society and Sustainability) research group (http://www.3s.uea.ac.uk/) within the School of Environmental Sciences.

Bond, A, A Morrison-Saunders and R Howitt, (editors). (2013), Sustainability Assessment: Pluralism, Practice and Progress, Built Environment Series. (Taylor and Francis, London).

Finn, J.A., Bartolini, F., Bourke, D., Kurz, I. and Davide, V. (2009) 'Ex post environmental evaluation of agri-environment schemes using experts' judgements and multicriteria analysis', Journal of Environmental Planning and Management, vol. 52, no. 5, pp. 717-737.

Lenihan, H and M Hart (2004), "The use of counterfactual scenarios as a means to assess policy deadweight: An Irish case study", Environment and Planning C: Government and Policy, 22(6), pages 817-839.

Lewis, D (1973), Counterfactuals (Basil Blackwell, Oxford).

Nelson, M and M K Mariedia (2007), "International agricultural research as a source of environmental impacts: Challenges and possibilities", Journal of Environmental Assessment Policy and Management, 9(1), pages 103-119.