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Responsive Design and Sampling Variability II

Just continuing the thought from the previous post...

Some examples of controlling the variability don't make much sense. For instance, there is no real difference between a response rate of 69% and one of 70%. Except for the largest of samples. Yet, there is often a "face validity" claim that there is a big difference in that 70% is an important line to cross.

However, for survey costs, it can be a big difference if the budgeted amount is $1,000,000 and the actual cost is $1,015,000. Although this is roughly the same proportionate difference as the response rates, going over a budget can have many negative consequences. In this case, controlling the variability can be critical. Although the costs might be "noise" in some sense, they are real.

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