Input-output (Leontief) production function is widely used in economic analysis. And diminishing marginal rate of return is a very well accepted economic fact. Leontief production function normally results in a linear production possibility frontier (PPF) due to its linear feature, whereas diminishing marginal rate of return implies a non-linear PPF. In this paper, the authors aim to fix this problem by considering multiple primary inputs in a simplified two-sector economy. The authors find that it is possible to curve a non-linear PPF by using Leontief production function when the authors add heterogeneous primary inputs. The authors also discuss the PPF using non-linear production function. Furthermore, the authors propose that three commonly used economic presumptions cannot hold in the same framework. These presumptions are “single primary input”, “fixed-proportion inputs” and “law of diminishing marginal returns”.

投入产出（Leontief）生产函数被广泛用于经济分析中。边际收益率递减是一个广为接受的经济事实。由于其线性特征，列昂蒂夫生产函数通常会导致线性生产可能性边界（PPF），而边际收益率递减意味着非线性PPF。在本文中，作者旨在通过考虑简化的两部门经济中的多个主要投入来解决此问题。作者发现，当作者添加异构初级输入时，可以通过使用Leontief生成函数来弯曲非线性PPF。作者还讨论了使用非线性生产函数的PPF。此外，作者提出，三个常用的经济假设不能在同一框架中成立。