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The Liquids ban is a worse idea than you thought

According to new research at Duke University, identifying an easy-to-spot prohibited item such as a water bottle may hinder the discovery of other, harder-to-spot items in the same scan.

Missing items in a complex visual search is not a new idea: in the medical field, it has been known since the 1960s that radiologists tend to miss a second abnormality on an X-ray if they’ve found one already. The concept — dubbed “satisfaction of search” — is that radiologists would find the first target, think they were finished, and move on to the next patient’s X-ray.

Does the principle apply to non-medical areas? That’s what Stephen Mitroff, an assistant professor of psychology & neuroscience at Duke, and his colleagues set out to examine shortly after 2006, when the U.S. Transportation Security Administration banned liquids and gels from all flights, drastically changing airport luggage screens.

“The liquids rule has introduced a whole lot of easy-to-spot targets,” Mitroff said.

Duke University press release [link to longer works], Mitroff’s home page [link to no longer works], full paper [link to no longer works].

One comment on "The Liquids ban is a worse idea than you thought"

  • Ron says:

    I have that same problem when I’m looking for vulnerabilities in a Web application — if there is too much easy stuff, I tend to miss the hard stuff until they clean it up.

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