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Sorry I missed you...

This is another post in a series on currently used survey design features that could be "relabeled" as adaptive. I think it is helpful to relabel for a couple of reasons. 1) It demonstrates a kind of feasibility of the approach, and 2) it would help us think more rigorously about these design options (for example, if we think about refusal conversions as a treatment within a sequence of treatments, we may design better experiments to test various ways of conducting conversions).

The design feature I'm thinking of today has to do with a card that interviewers leave behind sometimes when no one is home at a face-to-face contact attempt. The card says "Sorry I missed you..." and explains the study and that we will be trying to contact them.

Interviewers decide when to leave these cards. In team meetings with interviewers, I heard a lot of different strategies that interviewers use with these cards. For instance, one interviewer said she leaves them every time, even if they stack up. Others used them less frequently after several failed attempts. In any event, they have the decision rules in their heads. (They also have a lot of "data" about each housing unit and more or less experience with making contact with households.) These rules seem to vary.

I could (and did) imagine an adaptive rule that would say when these cards should be left behind. I fit a model that included a bunch of interactions with the SIMY card and other characteristics of the housing unit. The result was a prediction about when SIMY card helped and when it hurt. I then delivered recommendations to interviewers based on these model estimates. The adaptive rule could be stated as:

1) If the SIMY card increase probability of contact on the next attempt, then leave it.
2) If the SIMY card descreases or doesn't effect the probability of contact on the next attempt, then don't leave it.

Whether this rule works or not, I don't know. The interviewers didn't follow the model recommendations.


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