Input price-input quantity relations and the numeraire
指出竞争性企业面临的投入品价格并非完全任意，尤其在长期中，行业间的投入产出关系导致价格相互关联，这使得向下倾斜的投入需求曲线概念面临困难，且其斜率符号依赖于计价物的任意选择。
The fact that a competitive agent faces 'given' input prices does not necessarily mean that these prices can be completely arbitrary, especially in the long run. An obvious case, but not the only one, is when there are input--output relations among industries. But as soon as long-run input price interrelatedness is taken seriously, the very conception of a downward sloping input demand curve encounters serious difficulties. Although one can always draw an input price--input quantity relation, its main qualitative property--the sign of its slope--is not generally independent of the arbitrary choice of numéraire. Copyright The Author 2009. Published by Oxford University Press on behalf of the Cambridge Political Economy Society. All rights reserved., Oxford University Press.