Calibration and Validation of Global Forest Products Model (GFPM)
description
Transcript of Calibration and Validation of Global Forest Products Model (GFPM)
Calibration and Validation of Global Forest Products Model
(GFPM)
Joseph Buongiorno, Shushuai ZhuUniversity of Wisconsin - Madison
Acknowledgements
USDA Forest Service Southern Research Station
James Turner
Jeff Prestemon
Objectives
• Synchronize GFPM and FAO data cycles
• Correct data errors
• Reconcile data with theory
• Assist users with automated procedures
• Check predictions with observations
Methods
• DataFAOSTATWorld Bank World Development IndicatorsElasticities and other parameters
• CalibrationData smoothingStatic or dynamic calibration with data correction
• ValidationCheck data consistencyCompare data and solution
Data 1: FAO Statistics
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Data 2: World Bank WDI
Data 3: Forest Resource AssessmentExtent of forest and other wooded land 2010
Country/area
Land area
Inland water(1 000
ha)
Countryarea
(1 000 ha)
Forest Other wooded land Other land (1 000 ha)
1 000 ha% of
land area 1 000 ha% of
land area Total
of which with
tree cover
Angola 58480 47 0 0 66190 - 0 124670
Botswana 11351 20 34791 61 10531 - 1500 58173
Comoros 3 2 0 0 183 - 0 186
Djibouti 6 n.s. 220 9 2092 - 2 2320
Eritrea 1532 15 7153 71 1415 - 1660 11760
Ethiopia 12296 11 44650 41 52685 - 799 110430
Kenya 3467 6 28650 50 24797 10385 1123 58037
Lesotho 44 1 97 3 2894 - 0 3035
Madagascar 12553 22 15688 27 29913 - 550 58704
Malawi 3237 34 0 0 6171 - 2440 11848
GDP Price Year
Fuelwood-developing countries 0.05 -0.10
Fuelwood-developed countries 0.22 -0.10
Sawnwood 0.22 -0.10 -0.003
Standard error 0.03 0.02 0.001
Plywood & veneer 0.41 -0.29 -0.009
Standard error 0.04 0.02 0.002
Particleboard 0.54 -0.29 -0.006
Standard error 0.07 0.02 0.002
Fiberboard 0.35 -0.46 -0.002
Standard error 0.06 0.02 0.002
Newsprint 0.58 -0.25 -0.008
Standard error 0.04 0.02 0.001
Printing & Writing 0.45 -0.37 0.003
Standard error 0.03 0.02 0.001
Other paper & Paperboard 0.43 -0.23 -0.004
Standard error 0.03 0.02 0.001
Data 4: Elasticities of Demand
Calibration Goal = GFPM InputsGFPM
Spreadsheet
Content Calibration
Demand Initial condition+elasticities Yes
Supply Initial condition+elasticities Yes
Forest Initial condition+elasticities+ forest growth parameters
Yes
Manufacture I/O coefficients, costs Yes
Recycling Max recycling Yes
Transportation Initial import, export, cost Yes
ExogChange GDP growth and other changes No
Calibration Procedure
Smooth data (optional)
world price (net exporter)Local price =
world price + transport cost (net importer)
Then, for each country, simultaneously:Estimate I/O coefficients & manufacturing
costsCorrect data if needed
Goal Programming
Minimize (calibrated - reported production) +(calibrated - expected input)
Subject to:
– Observed imports, exports, and prices
– Prior bounds on:• I/O coefficients• Manufacturing costs• Recycling rates
Objective Function
2/1)()()1()(min jwiwi j
ijYijYβwiYi
iYβZ i
Deviationfrom reportedproduction
Deviation from expectedinput
Weight=world price
Deviation of estimated from reported production
Deviation of estimated from expected input
iiYiYiqiY 0
jiijYijYjYijaijY ,0
Reported production
Prior I/O coefficient
Material balance
Non-negative manufacturing cost
iiYiwjwjjiY 0
ixmYYj
iji 0ii
Import & export, given
Output valueInput cost
Feasible range of input i for output j
Feasible post-consumer recovery
jiUijajYijY
LijajY ,
iUijr
jjxjm
jijYjYiY
Lijr
jjxjm
jijYjY )()(
bounds on I/O coefficients
Paper consumption
Recovery bounds
Calculated I/O coefficient
jiY
YA
j
ijij ,
Dynamic Calibration
• Purpose: Smooth yearly change of I/O coefficients
• Method:– Static calibration for each last 3 years– “Average” of calibrated I/O coefficients, production,
imports, and prices
GFPM Calibration Interface
Post Calibration Data Checks
• Consumption = production + import – export
• Prices:Net Exporter=World Price
Net Importer=World Price + Transport Cost
• Manufacturing cost= Output Price – Input Costs
• Recovered paper >= consumed waste paper
Input Data Check Results
Inputmanufacturing cost
Algeriaplywood
Derivedmanufacturing cost
GFPM Validation - Base YearCheck predicted = calibrated:Demand
QuantityPrice
Supply Quantity
Price
Manufacturing QuantityPriceManufacturing cost
Net Trade
GFPM Validation - Base Year
Algeria
sawnwood price
consumption
Long Term validation
• Set base year (e.g. 1980)
• Set exogenous variables (e.g. 1980-1995)• GDP
• GDP/capita
• Compare predictions and observations
Industrial Roundwood Production
Actual (1980 - 1994) Projections (1980 - 1994)
0
400000
800000
1200000
1600000
2000000
1980 1985 1990 1980 1985 1990
Year
Th
ou
san
d c
ub
ic m
ete
rs
Africa North/Central America South America Asia Oceania Europe Former USSR
Industrial Roundwood Net Trade
Actual (1980 - 1994) Projections (1980 - 1994)
-75000
-60000
-45000
-30000
-15000
0
15000
30000
45000
1980 1985 1990 1980 1985 1990
Year
Th
ou
san
d c
ub
ic m
ete
rs
Africa North/Central America South America Asia Oceania Europe Former USSR
Soldid Wood World Prices
Actual (1980 - 1994) Projections (1980 - 1994)
0
100
200
300
400
500
1980 1985 1990 1980 1985 1990
Year
1994 U
S$ p
er
cu
bic
mete
r
Industrial Roundwood Sawnwood & sleepers
Further Work
• Extend dynamic calibration– I/O and costs (consider all data simultaneously)
– Demand (elasticities of demand)
– Supply (elasticities of supply)
• Explore alternative trade theories– Export (monopolistic competition)
• Update long-term validation
GFPM Software, Data, Manuals
http://fwe.wisc.edu/staticsites/buongiorno/book/GFPM.html