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Web Panels vs Mall Intercepts

I saw this interesting article that just came out. It called to my mind a talk that was hosted here a few (8?) years ago. The talk was someone from a major corporation who talked about how they switched product testing from church basements to online panels. They found that once they switched, the data became worse. The online panels picked products that ended up failing at higher rates.

This seemed like a tough problem. There isn't much of a "nonresponse" kind of relationship here. But at least understanding the mechanism that got people into online panels and how they were then selected and agreed to participate in this kind of product testing seemed important. It's not my area, so I'm wondering if this has ever been done. Not that anyone would understand the process of recruiting people to participate in product testing in church basements. But that process at least worked.

This new article looks at an old process -- mall intercepts -- for recruiting people to an experiment and compares it to a new process -- online panels. The data are from 2006. The demographics of those recruited are very different. There are many more young people in the mall intercept study. But the results are basically the same for the experiment for both recruitment strategies.

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  1. Exist polls are variation of intercepts and seem to work.

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