Mark Blumenthal has an interesting discussion of the accuracy of opt-in, online surveys as compared to those of traditional, telephone-based polls. While he takes issue with those who use the term “margin of error” with respect to the former, he nonetheless argues that they are becoming much more reliable.
I share Blumenthal’s concerns about opt-in surveys, and not just because my wife’s livelihood is tied to a polling firm that relies on traditional methodologies. Still, he’s right that survey research increasingly relies on weighting to control for demographic skews inherent in land-line telephone surveys and growing non-response rates. At some point, telephone surveys become essentially opt-in, too.
It wouldn’t surprise me if online polls caught up to and even supplanted telephone surveys in the not-too-distant future. My expectation is that firms, such as the one that employs my wife, will simply adapt. The art of interpreting polling data is only marginally tied to the technical means by which it is collected.
