Aggregation without separability: Tests of the United States and Mexican agricultural production data

The generalized composite commodity theorem (GCCT) and testing procedure is extended to Lest for consistent aggregation of the United States and Mexic an agricultural production data in each category for which earlier tests re jected homothetic separability. Nonrejected GCCT and separability hypothese s provide empirical support for aggregating all the United Stales agricultu ral outputs into as few as two categories: crops and livestock. Mexican agr icultural outputs also can be aggregated into as few as two categories. Sup port for aggregating all outputs into a single category is ambiguous in bot h countries and is only provided by the GCCT.