The complex relationship between technologies and other components of the
agricultural economy limits effective forecasting of the economic benefits to
be gained from alternative agricultural research investments. This is particularly
true in sub-Saharan Africa, where agricultural production systems are
characterized by tremendous diversity and rapid change. The horticultural
program priority-setting exercise discussed in the previous chapter demonstrates
that population growth and market structure can be important determinants
of potential agricultural research benefits. However, concerns are
commonly raised when using economic-surplus-based measures that two key
factors are not adequately captured in the analysis. The first factor is the future
nonresearch-induced growth (or decline) in production of specific commodities.
The second factor is the social benefits to be gained by targeting
research directly to poor households