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Estimating effort in field surveys

One of the things that I miss about telephone surveys is being able to accurately estimate how much various activities cost or even how long each call takes. Since everyone works on a centralized system on telephone surveys, and everything gets time-stamped, you can calculate how long calls take. It's not 100% accurate -- weird things happen (someone takes a break and it doesn't show up in the data, networks collapse, etc.) but usually you can get pretty accurate estimates.

In the field, the interviewers tell us what they did and when. But they have to estimate how many hours each subactivity (travel, production, administration) takes, and they don't give anything at the call level.

I've been using regression models to estimate how long each call takes in field studies. The idea is pretty simple, regress the hours worked in a week on the counts of the various types of calls made that week. The estimated coefficients are the estimate of the average time each type of call talks. This still isn't perfect, but it gets a conversation started.

In the past, I have used this idea to try and forecast survey outcomes. Now I'm trying to use it to compare two waves of a survey to see if there are differences. I'm looking for other uses of the technique since I think it is kind of neat.

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