1. Econometric-Process Simulation Models for Semi-Subsistence Agricultural Systems: Application of the NUTMON Data for Machakos

2. Various features of semi-subsistence ag pose challenges to modeling: low specialization, high diversification, many crops and livestock complex intercropping high rates of crop failure limited use of purchased inputs small parcels, changes in parcel configuration between seasons family and hired labor

3. Various features of semi-subsistence ag pose challenges to modeling (cont.): partially observed prices (incomplete input and output markets) transaction costs high and difficult to measure (transport, information) weak institutions (legal, property rights, financial) Implication: conventional models and statistical analysis may lead to faulty inferences and predictions.

4. Integrated Assessment Approach to Modeling Ag. Production Systems

5. Econometric-Process Simulation Models Use econometric production models to parameterize statistical simulation model of land use (extensive margin) and input use (intensive margin) decisions of farmers Use crop models to estimate spatial variation in productivity and simulate scenarios Use spatially referenced data to characterize spatial distributions of land use and management

6. New Developments in E-P Simulation Models Earlier models focused on ag-environment interactions at the field scale For analysis of semi-subsistence systems need whole farm analysis –Crop-livestock interactions –Poverty and food security indicators

7. Design of the Machakos EP Simulation Model

8. Machakos Variable Means

9. Machakos Parcel Size Distribution

10. Machakos Mineral Fertilizer Distribution, Maize

11. Machakos Maize Yield Distribution

12. How well do the models work?