Using Panel Data to Estimate Risk Effects in Seemingly Unrelated Production Functions.

In this paper, production functions in the form of seemingly unrelated regressions (SUR) with errors that are heteroscedastic and that contain cross-section and time components are proposed. These functions are distinguished from others in that they allow the risks (indicated by variances) of outputs to change in any direction in response to input changes. The SUR are then applied in the analysis of cross-section time-series data for rice, wheat, and maize production in China.