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Paradata and Total Survey Error

At the recent Joint Statistical Meetings I was part of an interesting discussion on paradata and nonresponse. At one point, someone reported that their survey had reduced the number of observations being recorded by interviewers. They said the observations were costly in a double sense. First, it takes interviewer time to complete them. Second, it diverts attention from the task of gathering data from persons willing to respond to the survey.

I have to say that we certainly haven't done a very good job of determining the cost of these interviewer observations. First, we could look at keystroke files to estimate the costs. This is likely to be an incomplete picture as there are times when observations are entered later (e.g. after the interviewer returns home). Second, we could examine the question of whether these observations reduce the effectiveness of interviewers in other errors. This would require experiments of some sort.

Once these costs are understood, then we can place them in a total survey error perspective. These observations have some cost. Is that cost justified by their utility in reducing nonresponse biases? For example, for a fixed budget obtaining these observations might require that I reduced my sample size by a certain amount (possibly by lowering the response rate). But the accuracy of weighted estimates might improve with these interviewer observations such that the total error is reduced.

I don't know of any evaluations of interviewer observations from this perspective. But it seems like a logical next step.

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