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Was it done on Walmart shoppers? That would be a huge selection bias.
by mertd 14y ago
Was it done on Walmart shoppers? That would be a huge selection bias.
- evmar 14y agoBriefly, no. You can read more about on our site (it's mentioned at the end of the article), but: we (try to) survey a representative sample of people in the US, and external validations have found we do a pretty good job of it (comparable to a more reputable polling organization).