Case-level Phases

Groves and Heeringa conceived of design phases as a survey-level attribute. But nothing prevents us from thinking of methods for using the technique at a case-level.

In the last post, I talked about formalizing the concept of "phase capacity" using stopping rules. It might be that a similar logic could be used to formalize decisions at the case level.

For instance, a few years ago on a telephone survey we implemented two-phase sampling. We implemented the phase-boundary using a case-level rule: after a certain number of calls, you entered the second phase. There might be other ways in which stopping rules like this could be used in order to change the design at the case level.

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Assessment of Maching Learning Classifiers

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