The frontier production function, a parametric function of any form, can be estimated by sample data . this study shows that the projected panel data, which is the inputs and relative exponential maximum output data set, obtained by conducting the data envelopment analysis with the log inputs and output, is approximately piecewise cobb-douglas under a certain assumption 根據前沿生產函數的定義,本文利用投入產出的對數形式和數據包絡分析方法求出了相對指數最大產出,并證明了在一定的條件之下,這種數據結構即所謂的支撐面板數據具有分段近似cobb-douglas性。