Quasi-Concave (Composition) Functions with Nonconcave Argument Functions
证明，当复合函数中的某些自变量函数是非凹但拟凹时，复合函数仍可保持拟凹性，这对家庭生产模型和贸易理论中的某些应用有重要意义。
The concavity assumption in the known composition mapping result may be too restrictive for certain applications in the household production model and trade theory. The author shows how quasi-concave composition functions are generated when among the arguments are nonconcave, but still quasi-concave, functions. Copyright 1992 by Economics Department of the University of Pennsylvania and the Osaka University Institute of Social and Economic Research Association.