separability conditions for aggregation have been rejected is reconsidered to determine if aggregation can be based on the GCCT … of formulating aggregates prior to conducting tests for aggregation is addressed. …

Consistent aggregation of production data across commodities and states was tested using Lewbel's generalized composite … commodity theorem (GCCT). This was the first empirical GCCT test for consistent geographic aggregation and was applied to two … groups of states. Consistent commodity aggregation was tested in all states for two output groups and three input groups and …

The generalized composite commodity theorem (Lewbel 1996) is used to test for consistent aggregation of U.S. and … aggregated into as few as five categories. The aggregation of all outputs into a single output cannot be supported in either …

-agriculture. Standard aggregation procedures ignore the variability within sectors, and underweight the importance of highly protected … that using optimal aggregation procedures increases the measured importance of agricultural trade reform relative to non …

farmers' needs, expensive, benefiting agro-business, risk of decreased biodiversity), but does indicate that contamination of …

, and on attributes associated with both business arrangements. Risk-averse farmers should be willing to pay a risk premium … for the reduction in price risk provided by a contract. Farmers with a preference for "autonomy" should be willing to pay … and own the commodity they produce. The benefits to growers from contracting (such as risk reduction) may be over …