ABSTRACT
The principal function served by parametric tr end analysis is to determine the relative contribution of linear , quadratic, and higher -order polynomial functions to the variation of measur ements over a quantitatively or dered series of treatments. The trend tests in this chapter have a different function, which is to test H
of no treatment effect by using a test statistic sensitive to a certain type of tr end that is expected. If the pr edicted trend is realized in the data, the trend test will be more sensitive than without a trend prediction, but it must be noted that randomization tr end tests do not test hypotheses about trends; they simply use test statistics sensitive to tr end which test the null hypothesis of no dif ferential treatment effect.
