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Outline. Why farm type models ? FADN as data source Integration in the data base Integration in the modeling system Exploitation Unresolved issues. Why farm type models. Farm specialization matters: regarding environmental impacts (stocking densities etc.)
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Outline • Why farm type models ? • FADN as data source • Integration in the data base • Integration in the modeling system • Exploitation • Unresolved issues
Why farm type models • Farm specialization matters: • regarding environmental impacts(stocking densities etc.) • regarding policy impacts(farm specific ceilings) • regarding model behavior<=> linkages between activities, especially fodder crops and animals
FADN as data source • Farm Accounting Data Network (FADN): • single farm records covering revenues and costs, production program and certain yields, premiums • but no input allocation • not always clear link to administrative NUTS regions(instead own “FADN” regions) • differences in activity/product breakdowncompared to CAPRI • restricted access due to confidentiality issues
Integration in the data base • Four Step Procedure: • (1) Selection from FADN records • (2) Perfect aggregation of single farms to NUTS II • (3) Aggregation from single farm to farm types • (4) Integration in CAPRI data base
Integration of FADN, Step 1 • select/aggregate/distribute FADN itemsaccording to CAPRI product list Mapping toCAPRI product list FADNrecords FADNCAPRIrecords • Per farm in sample: • Activity levels • Production • Aggregation weights • Farm classification
Integration of FADN, Step 2 • ensure perfect aggregation from individual FADN recordsto NUTS II data in CAPRI data base Consistency(Levels, Output) FADNCAPRIrecords CAPRI database
Integration of FADN, Step 2 • Ensure perfect aggregation by simultaneous determination of optimal correction factors of single farm records for : • activity levels (ha, herd sizes) • yields • aggregation weights • aggregation weights are distributed over regions(a single farm in one region may be “typical” for farmsin other regions as well) => more observations for specific types => no problems with confidentiality limit • Technically: entropy penalty function
Integration of FADN, Step 3 • select the five most frequent types per region • aggregate remaining farms into “residual type” Consistency(Levels, Output)Assignmentto NUTS FADNrecords 6 Typesper region CAPRIdatabase
Integration of FADN, Step 3 • How are types selected ? • Three-digit classification of economic specialization(e.g. 202 Specialist flowers and ornamentals) • Sum up aggregation weights per type and region=> represent number of farms • Select five most frequent ones=> selection by number of agents, not necessarily by economic/environmental impact • all remaining farms aggregated into “residual group”
Integration FADN in the data base CoCo REGIO Consistency(Levels, Output)Assignmentto NUTS 6 Typesper region FADNrecords CAPREG CAPRIdatabase
Integration in the modeling system • Each farm type is treated like a “NUTS III” region • No change in the structure of the supply models • Consequently, now about 1050 regional aggregate modelson the supply side • aggregation to NUTS II/Member State/EUfor premium and market modules
Exploitation CAPRIRegionalisedData Base Mappingtool EXCELetc. CAPRIModellingSystemFarm types Aggregation NUTS II Aggregation MS,EU HTMLtables CAPRIResultData Base DAOUT
Unresolved Issues • Continuous access to FADN data • Farm specific constraints ? • Farm specific policy ceilingse.g. stocking density restrictions • tremendous increase in memory allocationand solution time of complete modelling system