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Slowly Declining Response Rates are the Worst!

I have seen this issue on several different projects. So I'm not calling out anyone in particular. I keep running into this issue. Repeated cross-sectional surveys are the most glaring example, but I think it happens other places as well.

The issue is that with a slow decline, it's difficult to diagnose the source of the problem. If everything is just a little bit more difficult (i.e. if contacting persons, convincing people to list a household, finding the selected person, convincing them to do the survey, and so on), then it's difficult to identify solutions.

One issue that this sometimes creates is that we keep adding a little more effort each time to try to counteract the decline. A few additional more calls. A slightly longer field period. We don't then search for qualitatively different solutions.

That's not to say that we shouldn't make the small changes. Rather, that they might need to be combined with longer term planning for larger changes. That's often difficult to do. But another argument for ongoing experimentation with new methods.


  1. Agreed. I think we should look more to IT people and how they use A/B testing. If we decide to change our fieldwork procedures, fine. Just keep 25% isolated from the change, so we can actually estimate whether the thing we do helps.


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