treated. Estimates of investment, cost, and revenue can then be reported with any of the physical input values as denominator.

Comprehensive analysis of prospective policy change requires a systems approach that captures direct and indirect effects. Criteria to evaluate air emission mitigation techniques should produce sufficient information to predict all relevant effects at the individual farm level, as well as at local, regional, and national levels.

Beyond the scope of the interim report but to be addressed in the final report is a broader discussion of the economics of policy change with respect to air emissions from livestock operations. Among the issues to be considered are the following:

• comparative response of farm managers to incentives versus regulations,

• the potential for value-added products from livestock manure and the associated potential to reduce waste and emissions,

• a consideration in the policy analysis of market structure including vertical integration,

• an expanded discussion of benefits estimation, and

• the analytical implications of global competitiveness.