probabilistic causal models for nutrition outcomes of ... · conclusions •decision analysis is a...

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Probabilistic Causal Models for Nutrition Outcomes of Agricultural Actions Eike Luedeling Cory Whitney

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Page 1: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

Probabilistic Causal Models for Nutrition Outcomes of

Agricultural Actions

Eike Luedeling

Cory Whitney

Page 2: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

http://hdsa.org/wp-

content/themes/hdsa/images/img_livingHD_nutrition1.jpg

http://www.tatachemicals.com/upload

/images/masthead/Agriculture.jpg

How can we study the Agriculture-Nutrition linkage…?

Page 3: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

http://hdsa.org/wp-

content/themes/hdsa/images/img_livingHD_nutrition1.jpg

http://www.tatachemicals.com/upload

/images/masthead/Agriculture.jpg

…if the link isn’t direct?

How can we study the Agriculture-Nutrition linkage…?

Page 4: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

http://www.tatachemicals.com/upload

/images/masthead/Agriculture.jpg

http://hdsa.org/wp-

content/themes/hdsa/images/img_livingHD_nutrition1.jpg

…and involves many “confounding” factors?

…if the link isn’t direct?

How can we study the Agriculture-Nutrition linkage…?

Page 5: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

The statistical challenge may not look like this:

Page 6: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

…but like this:

A serious

challenge to our

common

statistical

procedures!

We’ll need deeper systems understanding to study this!

Page 7: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

Confronting complexity

• A rather daunting challenge (?)

• Complete, ‘objective’ understanding may not be attainable (or prohibitively costly)

• Fortunately, for deciding whether an intervention works, we may not need to know everything…

• …and we can build on existing knowledge held by locals and experts

• Is existing knowledge sufficient for deciding whether a specific intervention works?

• If not, what do we need to measure?

Decision Analysis answers these questions

Page 8: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

Causal decision model development with stakeholders

KenyaFruit trees on farms

UgandaVision 2040

Homegardens vs.

commercial farms

Page 9: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

Decision Analysis

Page 10: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

The Uganda Vision 2040 model

Page 11: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

Conclusions

• Decision Analysis is a useful paradigm for ANH research

• It is important that we consider causality and adequately represent complexity

• Precise knowledge on complex agricultural systems can’t realistically be achieved at scale – fortunately it’s often not needed

• Decision Analysis provides strategies for using our state of knowledge (incl. uncertainty) to compare decision options and evaluate interventions

• Still work to do on adapting Decision Analysis approaches to work on agricultural development contexts

Page 12: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

Our IMMANA experience

• Specific program to identify innovative approaches, which are urgently needed!

• Safe space to try new methods

• Fostered a necessary interdisciplinary conversation

• Incubator of innovation and ideas for future work

• Very well managed, incl. flexible where flexibility was needed

Thanks IMMANA!

Page 13: Probabilistic Causal Models for Nutrition Outcomes of ... · Conclusions •Decision Analysis is a useful paradigm for ANH research •It is important that we consider causality and

Bayesian Network modeling

• Causal modeling approach

• Each node is related to its parents through conditional probability tables (if parent = A, then child = B)

• Each table only describes one relationship, which is usually easy to consider

• Probabilistic linkage

• Allows considering uncertainty and risk in a quantitative model

• Value of Information analysis, a capability added by this project, allows highlighting critical uncertainties