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Hugh Possingham FAA ARC Federation Fellow and ARC Centre of Excellence Director (as of Jan 2011) Professor of Mathematics and Professor of Ecology (50/50) The University of Queensland Read – www.aeda.edu.au/news. Stochastic optimisation, risk and uncertainty; what is the problem?. - PowerPoint PPT Presentation
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Hugh Possingham FAAARC Federation Fellow and ARC Centre of Excellence Director (as of Jan 2011)Professor of Mathematics and
Professor of Ecology (50/50)
The University of Queensland
Read – www.aeda.edu.au/news
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
Stochastic optimisation, risk and
uncertainty; what is the problem?
University of QueenslandSpatial Ecology Lab
cost
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
What is the problem?
What are the environmental assets and which ones are the highest priority – we could use classical conservation planning approaches to identify the highest priority wetlands and send the water there.
A but ignores costB include? but how?
Prioritisation- Scores- use Marxan or C-plan?
18
20
33
700 wetlands?18 major assets?
Y(t) R(t)
Z1(t)
Z3(t)
x(t)
v3(t)
v1(t)
w1(t)w2(t)
O(t)
Markov DecisionProcess,MDP
Z2(t) v2(t)
Ensure environmental assets meet predetermined stochastic targets – e.g. management will deliver a flood event to as much red gum as we can with 90% probability every ten years and 98% every 15 years. Condition as a state variable – highly adaptive Optimise using SDP (Grafton. Kompas et al) for min lost short term opportunity cost
cost
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
What is the problem
– dynamic and stochastic?
Include system dynamics (ground and surface)? What is an acceptable level of risk for an environmental asset? State-dependent stochastic optimisation – how bad is it to ignore stochasticity? Do we have the skill set to do this?
cost
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
Problem statement issues
Minimise opportunity cost of environmental outcomes with a particular certainty vs
Maximise environmental outcomes for a fixed cost
Maximise a weighted sum of outcomes
Risk aversion/variability/preferences?
cost
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
Setting objectives/single player
1 Choose the strategy that delivers an acceptable outcome at least 95% of the time
2 Info-gap – choose the strategy that delivers a base level outcome for the greatest amount of unfavourable uncertainty (precautionary) – we have two water allocation info-gap papers in preparation
cost
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
Uncertainty
cost
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
Adaptive management and learning
Are we doing active or passive adaptive
management? Do we even know what that
means? Do we have a learning plan that
maximises learning within socio-economic
constraints – or is there no broad-scale
experimentation. Is there are partial-
observability problem? (POMDP)
1 One player strategy assuming the water users behaviour is known or partially controlled
2 Buy and sell water assuming the system is a game
3 Create multiple environmental managers all with different environmental objectives and all with the power to buy and sell water (easements, diversions, entitlements, short or long terms etc.)
cost
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
Ignore command and control
A Individual wetland managersB Individual biological assets – eg treat
river red gums like a crop, or opening the mouth like a crop, or spoonbill breeding like a crop
“I am the environmental water holder for royal spoonbills”
Determine rules and test using experimental economics
cost
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
Or treat env assets like businesses –
harness power of human brain
cost
the ecology centreuniversity of queensland
australiawww.uq.edu.au/spatialecology
Is more and more data collection an excuse for not defining the
problem?
