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http://www.madagasikara-
voakajy.org/index.php
Assessing the impact of
environmental management interventions on ecological
outcomes
Julia P. G. Jones1, Ranaivo Rasolofoson1,2, Edwin Pynegar1
1School of Environment, Natural Resources and Geography, Bangor University
2 Department of Food and Resources Economics, University of Copenhagen
“Those who cannot learn from history are doomed to repeat it”
Georges Santayana 1863-1952
Key message: social phenomena influence impact evaluation of environmental management interventions
Randomised Control Trial: units are allocated to the intervention group or control group randomly
Intervention Control
Random allocation
Randomised Control Trials: mainstay of much applied ecology
RCTSs are increasingly advocated for more complex environmental interventions
It is well recognised that impacts of an intervention may ‘spill over’ (from control to intervention units)
Such ‘biophysical spill-over’ may mask the impact of the intervention
Imitation of the intervention in control areas (social spill over) can mask the true impact of the intervention in an RCT
Important social phenomenon #1: interventions may be imitated in the control units (social ‘spill over’)
Pynegar, Gibbons, Asquith & Jones (submitted) What role should Randomised Control Trials play in providing the evidence base underpinning environmental management?
Intervention should have a direct impact on outcome of interest
Intervention aims to change behaviour
Change in behaviour should impact the outcome of interest
Interventions which aim to change behaviour are fundamentally different from those aiming to have a direct impact on outcome of interest….
John Henry effect (those in control group increase their effort)-will reduce apparent effect of the intervention
John Henry effect
Important social phenomenon #2: people behave differently when they are being experimented upon
Pynegar, Gibbons, Asquith & Jones (submitted) What role should Randomised Control Trials play in providing the evidence base underpinning environmental management?
Intervention Control
Pre-matching comparison
Post-matching comparison
Matching
Quasi-experimental approach: units in intervention group are “matched” with control units which are as similar as possible
Relative effectiveness of different approaches to Community Forest Management at delivering conservation outcomes in Madagascar?
CFM which do not allow commercial forestry
CFM which do allow commercial forestry
Matched based on:
Proximity to recent deforestation
Proximity to a road
Proximity to an urban centre
Quality of agricultural land
Altitude
Result: CFM which allows commercial logging appears to have increased deforestation, CFM which does not allow commercial logging appears to have reduced deforestation
Source: Rasolofoson, Ferraro, Jenkins & Jones (submitted) The effectiveness of Community Forest Management at slowing deforestation in Madagascar
BUT: We know CFM (and the types of CFM) were not allocated randomly, there will likely be reasons (social/political/historical) not captured in our matching variables
Important social phenomenon #3: True matching is challenging without social/institutional understanding
of process of allocation to the intervention
http://www.madagasikara-
voakajy.org/index.php
Conclusions
• Talk of a ‘gold standard’ for impact evaluation is unhelpful.
• Social phenomena influence evaluation of the impacts of ecological management interventions and perhaps deserve more attention.
http://www.madagasikara-
voakajy.org/index.php
Thanks (@juliapgjones)
Nigel Asquith Paul Ferraro James Gibbons Clinton Jenkins
Edwin Pynegar Ranaivo Rasolofoson