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What is the right periodicity?

It seems that intensive measurement is on the rise. There are a number of different kinds of things that are difficult to recall sufficiently over longer periods of time where it might be preferred to ask the question more frequently with a shorter reference period. For example, the number of alcoholic drinks consumed by day. More accurate measurements might be achieved if the questions was asked daily about the previous 24 hour period.

But what is the right period of time? And how do you determine that? This might be an interesting question. The studies I've seen tend to guess at what the correct periodicity is. I think it's probably the case that it would require some experimentation to determine that, including experimentation in the lab.

There are a couple of interesting wrinkles to this problem.

1. How do you set the periodicity when you measure several things that might have different periodicity? Ask the questions at the most frequent periodicity?

2. How does nonresponse/attrition fit into this? If some people will only respond at a certain rate, what should you do? Is it better to force the issue with them, i.e. make an ultimatum that they participate at the rate we desire or not at all; or better to allow them to participate at their preferred rate?

I'm sure the answers vary across the substantive areas of interest. But it does seem like an interesting set of problems in the evolving world of survey research.


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