Global Futures & Strategic Foresight (GFSF) program enhances and uses a coordinated suite of biophysical and socioeconomic models to assess potential returns to investments in new agricultural technologies and policies. These models include IFPRI’s International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT), hydrology and water supply-demand models, and the DSSAT suite of process-based crop models. The program also provides tools and trainings to scientists and policy makers to undertake similar assessments. GFSF program is a Consultative Group on International Agricultural Research (CGIAR) program led by the International Food Policy Research Institute (IFPRI)

1. 1
Introducing IMPACT 3: Modeling
Philosophy and Environment
Sherman Robinson
Daniel Mason-D’Croz
Shahnila Islam

2. Global Futures and IMPACT
• Objective: Use IMPACT for ex-ante analysis of potential agricultural
technologies to help policy makers prioritize agricultural
investments
• Phase 1: IMPACT Developments:
– Welfare Module
– Benefit-Cost Analysis
– Technology Adoption Module
– Tracking progress against MDGs
• Challenges identified in Phase 1:
– Insufficient geographic disaggregation
– Need to model more CG-mandate crops
– 2000 base year outdated
– Model needed to be recoded to allow for better integration with new
modules under development (water, livestock, fish, biofuels)
2

3. What is IMPACT 3?
• More than a new FAO download and cleaner
code
• A modeling-data platform built on modularity
and interoperability
– Harmonized Data
– Data driven
model specifi-
cation
– More flexible to
meet user needs
3

4. • IMPACT integrates
various models, which
often use similar input
data
• Better data sharing,
common definitions,
and clear responsibility
of data processing
removes redundancy
and improves quality
control
4
Why Data Harmonization?
IMPACT 3 FAO Database
Data Processing
Spatial disaggregation
Balance Demand, and Trade
with Production
Data Cleaning
Crop Production
Livestock
Production
Commodity
Demand and Trade
FAO Data Collection
Bulk Download

5. • IMPACT integrates
various models, which
often use similar input
data
• Better data sharing,
common definitions,
and clear responsibility
of data processing
removes redundancy
and improves quality
control
5
Why Data Harmonization?
IMPACT 3 FAO Database
Data Processing
Spatial disaggregation
Balance Demand, and Trade
with Production
Data Cleaning
Crop Production
Livestock
Production
Commodity
Demand and Trade
FAO Data Collection
Bulk Download
SPAM

6. • IMPACT integrates
various models, which
often use similar input
data
• Better data sharing,
common definitions,
and clear responsibility
of data processing
removes redundancy
and improves quality
control
6
Why Data Harmonization?
IMPACT 3 FAO Database
Data Processing
Spatial disaggregation
Balance Demand, and Trade
with Production
Data Cleaning
Crop Production
Livestock
Production
Commodity
Demand and Trade
FAO Data Collection
Bulk Download
SPAM
IMPACT

7. Shared Data Data Processing Data Users
FAO
Climate
Data
Exogenous
IMPACT
Parameters
Geospatial
and
Subnational
Data
SPAM
IMPACT
Models
Hydrology
Crop
Models
Land-Use
Model
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IMPACT Data-Model Environment

8. • FAO
– Crop Production
– Livestock Production
– Supply-Utilization
– Food Balance Sheets
– Water Stress
• Climate Data
– GCMS
– Generated Weather
• Geospatial and
Subnational Data
– Irrigation
– Subnational Statistics
– Crop suitability maps
– Population Density
• Exogenous IMPACT
Parameters
– Yield, Area Growth
– Elasticities
– Prices (AMAD)
– Population
– GDP
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Share Data

9. • SPAM - Spatial
Production Allocation
Model
• Land-Use Model
• DSSAT Crop Models
• Biofuel Model
• Hydrology Model
• Water Basin
Management Model
• Water Stress Model
• Food Model
– Crops
– Livestock
– Sugar
– Oilseeds
9
Models

10. Direct Users of FAO Using Processed FAO
SPAM
FAO:
Estimation
FAO
Climate
Data
Exogenous
IMPACT
Parameters
Geospatial
and
Subnational
Data
IMPACT
•Food
•Water Stress
•Water Demand
Shared Data
10
FAO Data

11. • FAO Bulk Download for
3-year average around
2005 (04-06)
• Harmonized
SPAM/IMPACT
commodity, and
geographic definitions
• Bayesian Work Plan
– Iterate with new
information
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Processing FAO Data
Source Data
(FAO, SPAM)
Feedback to
data source
Priors on values and
estimation errors of
production, demand,
and trade
Estimation by Cross-
Entropy Method
Check results against
priors and identify
potential data problems
New information to
correct identified
problems

12. Data Harmonization and Quality
• Too many cooks
– Climate change is modeled in Water and Crop
models for IMPACT
– Need to use same initial and processed climate
data
– Ensure crop shocks and water shocks are
compatible
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13. Users of Climate Data
Use Aggregated
Processed Climate Data
Crop
Models
Hydrology
FAO
Climate
Data
Exogenous
IMPACT
Parameters
Geospatial
and
Subnational
Data
IMPACT
•Food
•Water Demand
•Water Stress
Shared Data
13
Climate Change Consistency

14. Data Harmonization and Quality
• Building common geographical definitions
• Standardize mapping of data
• Share data (initial and processed)
14

15. Users of Geospatial and
Subnational Data
Use Aggregated Outputs
from direct users
SPAM
Hydrology
Crop Models
Land-Use
Model
FAO
Climate
Data
Exogenous
IMPACT
Parameters
Geospatial
and
Subnational
Data
IMPACT
•Food
•Water Demand
•Water Stress
Shared Data
15
Geospatial Data Users

16. Modularity – Data Partitioning
• IMPACT model is now data driven
– General code built on specific data structures
• Each dataset has unique problems
– Detox drivers vs. self-driving car
– Data Processing
is source-specific
– Model Inputs are
model-specific
16

17. Modularity – IMPACT Partitioning
• IMPACT model is now data driven
– General code built on specific data structures
• Each dataset has unique problems
– Detox drivers vs. self-driving car
– Data Processing
is source-specific
– Model Inputs are
model-specific
17

18. Benefits of Data Independence
• Cleaner Model Code
– Facilitate model transfer and training
• Data Processing and Model design are
independent tasks
• Model can run different data sources and
aggregations without modification
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