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Centralization vs Local Control in Face-to-Face Surveys

A key question that face-to-face surveys must answer is how to balance local control against the need for centralized direction. This is an interesting issue to me. I've worked on face-to-face surveys for a long time now, and I have had discussion about this issue with many people.

"Local control" means that interviewers make the key decisions about which cases to call and when to call them. They have local knowledge that helps them to optimize these decisions. For example. if they see people at home, they know that is a good time to make an attempts. They learn people's work schedules, etc. This has been the traditional practice. This may be because before computers, there was no other option.

The "centralized" approach says that the central office can summarize the data across many call attempts, cases, and interviewers and come up with  an optimal policy. This centralized control might serve some quality purpose, as in our efforts here to promote more balanced response. Or they might be designed to save costs and improve efficiency.

Of course, these two views are really the ends of a continuum, and most projects fall in the middle somewhere. But still, there is a tension over these competing views.

One key factor is the ability of the interviewers to use local information to improve their decisions. If they can do this, then local control can be helpful. In practice, interviewers vary in their ability to make use of local information. There might be some tipping point with interviewer ability where central control should cede to local control in order to produce better results. Finding that point and managing it can be difficult.

Regardless of this kind of efficiency consideration, I would still argue that there is a need for central control. That is, even if we have highly expert interviewing staff, I would still say there is a need for central control since only the central office can see imbalances that may develop in who is responding. No interviewer has a wide enough view to see those, and it isn't their focus.

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