Resumen de Sign and Wilcoxon tests for quadratic versus cubic regression

A. P. Gore, K. S. Madhava Rao

• In this paper sign and Wilcoxon tests for testing the null hypothesis of quadratic regression versus the alternative, cubic regression are proposed. It is shown that in the case of a simple design consisting of multiple Y observations at each of the four levels of x, the proposed tests perform reasonably well as compared to their parametric competitors, while in the case of a general design consisting of a large number of levels of x, the loss in Pitman efficiency is considerable. However their computational simplicity appears remarkable