Tracking Costs

As I mentioned in my last post, I have been reading an enormous number of papers on locating respondents in panel studies. One interesting thing that I have found is that tracking costs are often described in a manner different than I would have expected. I'm used to thinking of the costs of activities -- telephone calls, internet searches, face-to-face calls, etc. These activity costs can be summed up to total costs, and then averaged over number of cases located or number of cases interviewed.

I found a lot of papers reported costs as FTEs. This seemed a lot simpler. I found one review paper that summarized several other studies. They reported all the results as FTEs. This was nifty in that it was simple, and somewhat impervious to inflation and differences in pay rates -- so better than reporting dollar costs.

The downside is that the costs can't be rescaled when there are differences among panels in difficulty of being tracked. Some are more difficult and require more effort (calls, searches, etc.). It's difficult to revise an FTE-based estimate to account for these differences. An estimate based on effort, however, can be rescaled for expected changes in effort (not that it is easy to generate the right expectations about effort).

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