Aggregate Production Functions Revisited: The Mobility of Capital and the Rigidity of Thought
考察了资本流动性对生产函数加总条件的影响，发现加总的严格条件主要源于企业间的加总而非资本不可流动性，且并未出现真正的新条件。
Past work on aggregation of production functions has focused on aggregation over firms where technology is embodied in fixed capital. This paper shows that much of the stringency of the necessary conditions for aggregation resides in the nature of aggregation over firms and not in the immobility of capital. Roughly, when capital is mobile, aggregation is permitted for any group of factors under the union of the conditions which otherwise applied to aggregation of fixed or aggregation of movable factors, respectively. No truly new conditions appear. The results are also interpreted in terms of output aggregation.