Smartphone App Shows TSA Screeners Often Miss The Rare Items
December 5, 2013

Smartphone App Shows TSA Screeners Often Miss The Rare Items

Alan McStravick for - Your Universe Online

I can’t think of a single time during all of my travels where I’ve seen the TSA screener, firmly planted on their stool and staring at the most boring television broadcast ever, and thought, “That looks like fun.” But apparently I am alone in this. A smartphone app, developed by Kedlin Co., allows casual gamers to pretend they are baggage screeners and the game is more popular than you may think.

Using this app, a group of Duke University researchers decided to review some 20 million virtual searches that had taken place in the game to find that the identification of weapons and other illegal items really isn’t as easy as one might think. The team noted the app users often failed to identify objects that made a rare appearance on their screen.

"We're seeing that people are really bad at finding items that are not likely to appear," said Stephen Mitroff, PhD, associate professor of psychology and neuroscience and member of the Duke Institute for Brain Sciences.

Just like your friendly TSA screener, game players scan images that appear as an X-ray of a piece of carry-on luggage. They are tasked with finding any number of items, including guns, scissors and dynamite sticks, along with less threatening but still illegal items like bottles of liquids that are larger than the carry-on allotment.

The team published their findings in the journal Psychological Science.

For the study, the researchers reviewed data associated with gameplay between December 2012 and March 2013. They wanted to determine the frequency with which players were able to locate 78 different illegal items based on the frequency of the appearance of the item on their screens.

Of the total number, 30 of the objects were classified as “ultra-rare” due to their appearance of less than .15 percent of the time. The ultra-rare items, it turns out, were only correctly identified 27 percent of the time. By comparison, a target item with a higher than 1 percent frequency was able to be identified 92 percent of the time.

"This isn't a matter of overall vigilance or how frequently players responded, since half of the searches had a to-be-found item present," Mitroff said. "This effect is about being able to detect specific items and how likely you are to miss them when they occur infrequently."

As the team points out, a real-world example would be that a TSA screener is likely to encounter an item like a pocket knife with much higher frequency than he or she would be to come across a gun in someone’s luggage. The researchers' findings indicate that the screener would therefore be more conditioned to catch an illegal though comparatively less dangerous item due to its more frequent appearance.

"With the very large array of potential targets, the searchers seem to be highly sensitive to how frequently each individual target appeared, and they adjusted the focus of their searches so that targets that appeared rarely were a low priority," Mitroff said. "This situation may be what occurs in many real-world searches."

The findings of Mitroff and co-author Adam Biggs, a post-doctoral researcher from the psychology and neuroscience department in the Center for Cognitive Neuroscience, have led them to coin the term “ultra-rare item effect.” This effect, says Mitroff, allows rare objects to slip past us no matter how hard we’re looking for them or how critical finding them might be.

Though the team’s early hypothesis predicted such an effect, they were no less surprised at the strong relationship. This finding, says Mitroff, leaves the door open to further study into how an individual’s behaviors might be modified so they can find more of the ultra-rare items.

Additionally, Mitroff believes the Airport Scanner game could be an effective tool for the training of TSA employees. At this point in time, the team now has access to more than 1.5 billion trials from the smartphone app that they can subject to further analysis.

"We want to better understand why this happens." he said. "Are you attuned to more frequent items at the cost of others? If you don't see something very often, it makes sense that you don't want to waste energy looking for it, but at the end of the day you still want to detect some of these ultra-rare items."

The team, which received no outside funding, was able to receive each of the game play trials in accordance with the Standard Apple User agreement. Duke University offered approval of the analysis of the data for the study.


Image Below: A screen shot from the smartphone game Airport Scanner shows simulated baggage screening. There's part of a handgun in this bag. Duke researchers used more than 20 million bag searches from the game to discover that very rare items often go undetected. Credit: Airport Scanner by Kedlin