Abstract
There are multiple comparison procedures to identify a minimum effective dose level where the effect on a response first appears with increasing dose level in dose response test. These procedures are used to carry out the test based on the all observations obtained across all dose levels. However, if it is difficult to obtain the observations easily at each dose level or we want an early decision in the test based on few observations, it is meaningful to develop the procedure that identifies sequentially a minimum effective dose level based on the sequentially obtained observations. In this study, we propose a sequential contrast procedure to identify the minimum effective dose level by sequentially investigating the change of the response by using the contrast among population means. In simulation studies, we compare the sequential Dunnett's procedure developed and the sequential contrast procedure in terms of the power of the test. In a case study, we apply these two procedures to the dose response test on workability of mortar in concrete technology.
