| Abstract: | Economic theory must be subjected to continuous empirical testing and verification. Consequently any econometric model proposed may be re-tested and modified in the light of imporved data availability and additional observations generated by the real world. This paper re-examines U.D. aggregate demand for nitrogen: after otaining a meaningful data series for the price of nitrogen it is found that earlier functions fitted do not now stand up to the passage of time. Alternarte hypotheses are then put forward. |
