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Were we already adaptive?

I spent a few posts cataloging design features that could be considered adaptive. No one labelled them that way in the past. But if we were already doing it, why do we need the new label?

I think there are at least two answers to that:

1. Thinking about these features allows us to bring in the complexity of surveys. Surveys are multiple phase activities, where the actions at different phases may impact outcomes at later phases. This makes it difficult to design experiments. Clinical trials, some have labelled this phenomenon as "practice misalignments." They note that trials that focus on single-phase, fixed-dose treatments are not well aligned with how doctors actually treat patients. The same thing may happen for surveys. When something doesn't work, we don't usually just give up. We try something else.

2. It gives us a concept to think about these practices. It is an organizing principle that can help identify common features, useful experimental methods, and analytical perspectives. Methods for analyzing these complicated sequences have been developed in other fields. For example, methods from Operations Research and Computer Science may be helpful. See for example this article by Melania Calinescu and colleagues.

These past examples are also helpful when trying to justify adaptive designs to skeptical audiences. 



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