Does a SIMY card always help?

Although we don't have any evidence, our prior assumption seems to be that SIMY cards are generally helpful. Julia D'arrigo, Gabi Durrant, and Fiona Steele have a working paper that presents evidence from a multi-level multinomial model that these cards do improve contact rates.

A further question that we'll be attempting to answer is whether we can differentiate among cases for which the SIMY card improves contact rates and those for which it does not. Why would a card hurt contact rates? It might be that for some households, the card acts as a warning and they work to avoid the interviewer. Or, they may feel that leaving the card was somehow inappropriate. We have anecdotal evidence on this score.

In the models I've been building, I have found interactions between observable characteristics of the case (e.g. is it in a neighborhood with access impediments? Is it in a neighborhood with safety concerns?, etc.) that indicate that we may be able to differentiate our policy across cases with regards to the SIMY card. The plan is to estimate probabilities of contact with and without the card, and choose the policy with the higher probability of success on the next call.

Again, this is a greedy policy that hasn't worked too well in the telephone contact strategies experiments. But at least it's a start.

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