This article addresses the question of whether soybeans, soybean meal
and soybean oil produced in the USA and exported were part of a single
, world geographic market during the decade of the 1980s. An answer to
this question is sought using an approach to defining a geographic ma
rket based on the notion of instantaneous causality. The empirical res
ults, based on prices for soybeans, soybean meal and soybean oil for t
hree spatially diffuse locations, suggest that there was but a single
identifiable world market for these commodities over the period of stu
dy. This has implications for the continued presence of soybean produc
tion subsidies and discussions on international agreements designed to
reduce or eliminate these subsidies.