Using causal inference in environmental impact evaluation

Liz Law

More complex than BACI design, but you may not need as much information as you think

At the recent ICCB in Baltimore, I was lucky enough to score a place in the “Environmental impact evaluation and causal inference” workshop run by Paul Ferraro and Merlin Hanauer. I would highly recommend everyone working in conservation related fields to explore this field. Two of the main conclusions that I got out of this course were that: a) once again, my undergraduate education was flawed: before-after control-impact (BACI) is NOT the epitome of experimental design, particularly in the case of conservation impact evaluation, and b) to provide policy relevant information you may not need as much data as you think.

We’ve all heard the calls for evidence based environmental policy, and recognize the relative paucity of studies that evaluate conservation intervention effectiveness. Many have the common belief that the data for such evaluations is simply not available, often due to time and financial constraints as much as lack of motivation or will. Yet this belief may be constructed under false pretenses, a result of having BACI design celebrated so religiously through our undergraduate training. The field of causal inference and impact evaluation has long moved on.

 

Identifying causal effects

“Correlation does not imply causation and lack of correlation does not imply lack of causation.”

To identify causal effects we are really trying to eliminate rival explanations Continue reading Using causal inference in environmental impact evaluation

A modular framework for management of complexity in international forest-carbon policy

Elizabeth A. Law, Sebastian Thomas, Erik Meijaard, Paul J. Dargusch, Kerrie A. Wilson. 2012. A modular framework for management of complexity in international forest-carbon policy. Nature Climate Change 2:155-160. doi:10.1038/nclimate1376

Abstract

Complex and variable ecological and social settings make the programme on reducing emissions through avoided deforestation, forest degradation and other forestry activities in developing countries (REDD+) a challenging policy to design. The total value to society of each type of REDD+ outcome is dependent on the fundamentally different risk profiles of alternative forest-management approaches and their scope and potential for co-benefits. We suggest a modular policy framework for REDD+ that distinguishes and differentially compensates the distinct outcomes. This could represent an improved framework to promote and manage incentives for effective forest-carbon initiatives, offer better scope to find common ground in policy negotiations and allow faster adaptation of policy to an uncertain future.

REDD+ conceptual design under present policy (left-hand side) and a proposed modular framework based on separation of REDD+ outcomes (right-hand side).
Figure 1: REDD+ conceptual design under present policy (left-hand side) and a proposed modular framework based on separation of REDD+ outcomes (right-hand side).