Equal Effort... or Equal Probabilities

I've been reading an article on locating respondents in a panel survey. The authors were trying to determine what the protocol should be. They reviewed the literature to see what the maximum number of calls should be.

As I noted in my last post, I was recently involved in a series of discussions on the same topic. But when I was reading this article, I thought immediately about how much variation there is between call sequences with the same number of calls. The most extreme case is calling a case three times in one day is not the same as calling a case three times over the course of three weeks.

I think the goal should be to apply protocols that have similar rates of being effective, i.e. produce similar response probabilities. But there aren't good metrics to measure the effectiveness of the many different possibilities. Practitioners need something that can evaluate how the chain of calls produce an overall probability of response. Using call-level estimates might be one of getting such an estimate. The models would need to include factors for the different call windows that have been tried, possibly the sequence, time between calls. I worry that it gets too complex to model. Perhaps the sequence analysis of Kreuter and Kohler would be useful for this purpose.

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